U.S. patent application number 11/846989 was filed with the patent office on 2008-09-25 for method and system for determining channel spacing and configuring an fm transmitter.
Invention is credited to Scott Bibaud, Brima Babatunde Ibrahim, Siukai Mak, Bojko Marholev, John Walley.
Application Number | 20080233907 11/846989 |
Document ID | / |
Family ID | 39774089 |
Filed Date | 2008-09-25 |
United States Patent
Application |
20080233907 |
Kind Code |
A1 |
Ibrahim; Brima Babatunde ;
et al. |
September 25, 2008 |
Method And System For Determining Channel Spacing And Configuring
An FM Transmitter
Abstract
In a wireless communication system which may include a mobile
device having an integrated FM radio transmitter and a FM radio
receiver, a geographic location of the mobile device may be
determined. A FM channel map may be determined based on the
location and the FM radio transmitter may be configured for
transmitting FM signals based on the FM channel map, which may
include a list of ranked FM channels. The geographic location may
be acquired from received RDS or RBDS signals, received GPS
signals, other received wireless signals, and/or from user data.
Channel spacing, channel offset and/or frequency band may be
determined for the FM channel map. A frequency for transmitting FM
signals via the FM radio transmitter may be selected based on the
determined FM channel map. The FM radio receiver may also be
configured for receiving FM signals based on the determined FM
channel map.
Inventors: |
Ibrahim; Brima Babatunde;
(Aliso Viejo, CA) ; Bibaud; Scott; (Santa Ana,
CA) ; Mak; Siukai; (Poway, CA) ; Walley;
John; (Ladera Ranch, CA) ; Marholev; Bojko;
(Irvine, CA) |
Correspondence
Address: |
MCANDREWS HELD & MALLOY, LTD
500 WEST MADISON STREET, SUITE 3400
CHICAGO
IL
60661
US
|
Family ID: |
39774089 |
Appl. No.: |
11/846989 |
Filed: |
August 29, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60895665 |
Mar 19, 2007 |
|
|
|
Current U.S.
Class: |
455/183.2 |
Current CPC
Class: |
H03L 7/085 20130101;
H03L 7/181 20130101 |
Class at
Publication: |
455/183.2 |
International
Class: |
H04B 1/18 20060101
H04B001/18 |
Claims
1. A method for wireless communication, the method comprising: in a
mobile device comprising an integrated FM radio transmitter and FM
radio receiver: determining a geographic location of said mobile
device; determining a FM channel map based on said determined
location of said mobile device; and configuring said FM radio
transmitter for transmitting FM signals based on said determined FM
channel map.
2. The method according to claim 1, comprising acquiring said
geographic location from RDS or RBDS signals received by said radio
receiver.
3. The method according to claim 1, comprising acquiring said
geographic location from GPS data received via a GPS receiver
located said mobile device.
4. The method according to claim 1, comprising acquiring said
geographic location from wireless data received from a wireless
network via a wireless receiver integrated within said mobile
device.
5. The method according to claim 1, comprising acquiring said
geographic location from user data received by said mobile
device.
6. The method according to claim 1, comprising determining channel
spacing, channel offset and/or frequency band for said determined
FM channel map.
7. The method according to claim 1, comprising selecting a
frequency for transmitting FM signals via said FM radio transmitter
based on said determined FM channel map.
8. The method according to claim 1, comprising configuring said FM
radio receiver for receiving FM signals based on said determined FM
channel map.
9. The method according to claim 1, comprising configuring one or
both of said FM radio transmitter and FM radio receiver via an
in-band FM signal based on said determined FM channel map.
10. The method according to claim 1, comprising configuring one or
both of said FM radio transmitter and FM radio receiver via an
out-of-band signal based on said determined FM channel map
11. The method according to claim 10, wherein said out-of-band
signal comprises one or more of a Bluetooth signal, a WLAN signal,
a ZigBee signal, and a wireless signal.
12. The method according to claim 1, wherein said determined FM
channel map comprises a list of ranked FM channels.
13. The method according to claim 1, comprising generating a signal
that indicates a channel being used by said FM radio transmitter
based on said configuration.
14. The method according to claim 13, wherein said generated signal
comprises one or more of an audio signal, and/or a visual
signal.
15. The method according to claim 14, wherein said audio signal
comprises text-to-speech translation and/or one or more audible
tones.
16. A system for wireless communication, the system comprising: a
mobile device comprising at least one processor, and an integrated
FM radio transmitter and FM radio receiver, wherein: said at least
one processor enables determination of a geographic location of
said mobile device; said at least one processor enables
determination of a FM channel map based on said determined location
of said mobile device; and said at least one processor enables
configuration of said FM radio transmitter for transmitting FM
signals based on said determined FM channel map.
17. The system according to claim 16, wherein said at least one
processor enables acquisition of said geographic location from RDS
or RBDS signals received by said radio receiver.
18. The system according to claim 16, wherein said at least one
processor enables acquisition of said geographic location from GPS
data received via a GPS receiver located said mobile device.
19. The system according to claim 16, wherein said at least one
processor enables acquisition of said geographic location from
wireless data received from a wireless network via a wireless
receiver integrated within said mobile device.
20. The system according to claim 16, wherein said at least one
processor enables acquisition of said geographic location from user
data received by said mobile device.
21. The system according to claim 16, wherein said at least one
processor enables determination of channel spacing, channel offset
and/or frequency band for said determined FM channel map.
22. The system according to claim 16, wherein said at least one
processor enables selection of a frequency for transmitting FM
signals via said FM radio transmitter based on said determined FM
channel map.
23. The system according to claim 16, wherein said at least one
processor enables configuration of said FM radio receiver for
receiving FM signals based on said determined FM channel map.
24. The system according to claim 16, wherein said at least one
processor enables configuration of one or both of said FM radio
transmitter and FM radio receiver via an in-band FM signal based on
said determined FM channel map.
25. The system according to claim 16, wherein said at least one
processor enables configuration of one or both of said FM radio
transmitter and FM radio receiver via an out-of-band signal based
on said determined FM channel map
26. The system according to claim 25, wherein said out-of-band
signal comprises one or more of a Bluetooth signal, a WLAN signal,
a ZigBee signal, and a wireless signal.
27. The system according to claim 16, wherein said determined FM
channel map comprises a list of ranked FM channels.
28. The system according to claim 16, wherein said at least one
processor enables generation of a signal that indicates a channel
being used by said FM radio transmitter based on said
configuration.
29. The system according to claim 28, wherein said generated signal
comprises one or more of an audio signal, and/or a visual
signal.
30. The system according to claim 29, wherein said audio signal
comprises text-to-speech translation and/or one or more audible
tones.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS/INCORPORATION BY
REFERENCE
[0001] This application makes reference to and claims priority to
U.S. Provisional Application Ser. No. 60/895,665 (Attorney Docket
No. 18371US01), filed on Mar. 19, 2007, entitled "METHOD AND SYSTEM
FOR A SINGLE CHIP INTEGRATED BLUETOOTH AND FM TRANSCEIVER AND
BASEBAND PROCESSOR," which is incorporated herein by reference in
its entirety.
[0002] This application also makes reference to:
U.S. patent application Ser. No. 11/755,395 filed on May 30, 2007;
U.S. patent application Ser. No. 11/832,844 filed on Aug. 2,
2007;
[0003] Each of the above stated applications is hereby incorporated
herein by reference in its entirety.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0004] [Not Applicable]
MICROFICHE/COPYRIGHT REFERENCE
[0005] [Not Applicable]
FIELD OF THE INVENTION
[0006] Certain embodiments of the invention relate to FM
communication. More specifically, certain embodiments of the
invention relate to a method and system for determining channel
spacing and configuring an FM transmitter.
BACKGROUND OF THE INVENTION
[0007] With the popularity of portable electronic devices and
wireless devices that support audio applications, there is a
growing need to provide a simple and complete solution for audio
communications applications. For example, some users may utilize
Bluetooth-enabled devices, such as headphones and/or speakers, to
allow them to communicate audio data with their wireless handset
while freeing to perform other activities. Other users may have
portable electronic devices that may enable them to play stored
audio content and/or receive audio content via broadcast
communication, for example.
[0008] Some wireless devices may have the capability to handle a
plurality of protocols and may require separate processing hardware
and/or separate processing software. Moreover, coordinating the
reception and/or transmission of data to and/or from these mobile
wireless devices may require significant processing overhead that
may impose certain operation restrictions and/or design challenges.
In addition, radio communication standards for a variety of radio
technologies may not have taken into consideration methods for
communication between multiple technology devices.
[0009] Furthermore, handling a plurality of protocols may result in
significant increases in power consumption. Power being a precious
commodity in most wireless mobile devices requires careful design
and efficient processes in order to minimize battery usage.
Additional overhead such as sophisticated power monitoring and
power management techniques are required in order to maximize
battery life.
[0010] Further limitations and disadvantages of conventional and
traditional approaches will become apparent to one of skill in the
art, through comparison of such systems with some aspects of the
present invention as set forth in the remainder of the present
application with reference to the drawings.
BRIEF SUMMARY OF THE INVENTION
[0011] A system and/or method for determining channel spacing and
configuring an FM transmitter, substantially as shown in and/or
described in connection with at least one of the figures, as set
forth more completely in the claims.
[0012] Various advantages, aspects and novel features of the
present invention, as well as details of an illustrated embodiment
thereof, will be more fully understood from the following
description and drawings.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
[0013] FIG. 1A is a block diagram of an exemplary FM receiver that
communicates with handheld devices that utilize a single chip with
FM radios and one or more integrated radios such as Bluetooth, GPS,
WLAN, WWAN or a wire line connection, in accordance with an
embodiment of the invention.
[0014] FIG. 1B is a block diagram of an exemplary single chip with
multiple integrated radios that supports radio data processing, in
accordance with an embodiment of the invention.
[0015] FIG. 2 is a block diagram of an exemplary single chip that
supports FM operations and one or more of a plurality of optional
integrated transceivers. For example, in addition to FM, the chip
may support Bluetooth, GPS, WLAN, WWAN or other transceivers, in
accordance with an embodiment of the invention.
[0016] FIG. 3 is a block diagram of an exemplary FM core with FM
transmitter and PTU for processing RDS and digital audio data, in
accordance with an embodiment of the invention.
[0017] FIG. 4A is a flow chart for an exemplary algorithm that
enables determining channel spacing offsets when RDS/RBDS data and
user input are not available, in accordance with an embodiment of
the invention.
[0018] FIG. 4B is a block diagram of a plurality of exemplary radio
devices that enable frequency modulation (FM) transmission and
reception, in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Certain aspects of the invention may be found in a method
and system for determining channel spacing and configuring an FM
transmitter. In a wireless communication system which may include a
mobile device having an integrated FM radio transmitter and FM
radio receiver, a geographic location of the mobile device may be
determined. A FM channel map may be determined based on the
location and the FM radio transmitter may be configured for
transmitting FM signals based on the FM channel map, which may
include a list of ranked FM channels. The geographic location may
be acquired from received RDS or RBDS signals, received GPS
signals, other received wireless signals, and/or from user data.
Channel spacing, channel offset and/or frequency band may be
determined for the FM channel map. A frequency for transmitting FM
signals via the FM radio transmitter may be selected based on the
determined FM channel map. The FM radio receiver may also be
configured for receiving FM signals based on the determined FM
channel map.
[0020] The FM radio transmitter and/or FM radio receiver may be
configured via an in-band FM signal and/or via an out-of-band
signal based on the determined FM channel map. The out-of-band
signal may comprise one or more of a Bluetooth signal, a WLAN
signal, a ZigBee signal, and a wireless signal. A signal may be
generated to indicate a channel being used by the FM radio
transmitter based on the configuration. The generated signal may
comprise a visual signal and/or an audio signal for example,
text-to-speech translation and/or one or more audible tones.
[0021] FIG. 1A is a block diagram of an exemplary FM receiver that
communicates with handheld devices that utilize a single chip with
FM radios and one or more integrated radios such as Bluetooth, GPS,
WLAN, WWAN or a wire line connection, in accordance with an
embodiment of the invention. Referring to FIG. 1A, there is shown
an FM receiver 110, a cellular phone 104a, a smart phone 104b, a
computer 104c, and an exemplary FM device equipped with one or more
integrated transceivers 104d. In this regard, the FM receiver 110
may comprise and/or may be communicatively coupled to a listening
device 108. A device equipped with the FM and one or more
integrated transceivers, such as the single chip 106, may be able
to broadcast its respective signal to a "deadband" of an FM
receiver for use by the associated audio system. For example, a
cellphone or a smart phone, such as the cellular phone 104a and the
smart phone 104b, may transmit a telephone call for listening over
the audio system of an automobile, via usage of a deadband area of
the car's FM stereo system. One advantage may be the universal
ability to use this feature with all automobiles equipped simply
with an FM radio with few, if any, other external FM transmission
devices or connections being required.
[0022] In another example, a computer, such as the computer 104c,
may comprise an MP3 player or another digital music format player
and may broadcast a signal to the deadband of an FM receiver in a
home stereo system. The music on the computer may then be listened
to on a standard FM receiver with few, if any, other external FM
transmission devices or connections. While a cellular phone, a
smart phone, and computing devices have been shown, a single chip
that combines a Bluetooth and FM transceiver and/or receiver may be
utilized in a plurality of other devices and/or systems that
receive and use an FM signal.
[0023] FIG. 1B is a block diagram of an exemplary single chip with
multiple integrated radios that supports radio data processing, in
accordance with an embodiment of the invention. Referring to FIG.
1B, there is shown a single chip 130 that may comprise a radio
portion 132 and a processing portion 134. The radio portion 132 may
comprise a plurality of integrated radios. For example, the radio
portion 132 may comprise an FM receive and transmit (Rx/Tx) radio
140c that supports FM communications and a plurality of optional
integrated radios. For example, a cellular radio 140a that supports
cellular communications, a Bluetooth radio 140b that supports
Bluetooth communications, a global positioning system (GPS) 140d
that supports GPS communications, and/or a wireless local area
network (WLAN) 140e that supports communications based on one or
more of the IEEE 802.11 standards.
[0024] The processing portion 134 may comprise at least one
processor 136, a memory 138, and a peripheral transport unit (PTU)
140. The processor 136 may comprise suitable logic, circuitry,
and/or code that enable processing of data received from the radio
portion 132. In this regard, each of the integrated radios may
communicate with the processing portion 134. In some instances, the
integrated radios may communicate with the processing portion 134
via a common bus, for example. The memory 138 may comprise suitable
logic, circuitry, and/or code that enable storage of data that may
be utilized by the processor 136. In this regard, the memory 138
may store at least a portion of the data received by at least one
of the integrated radios in the radio portion 132. Moreover, the
memory 138 may store at least a portion of the data that may be
transmitted by at least one of the integrated radios in the radio
portion 132. The PTU 140 may comprise suitable logic, circuitry,
and/or code that may enable interfacing data in the single chip 130
with other devices that may be communicatively coupled to the
single chip 130. In this regard, the PTU 140 may support analog
and/or digital interfaces.
[0025] FIG. 2 is a block diagram of an exemplary single chip that
supports FM operations and one or more of a plurality of optional
integrated transceivers. For example, in addition to FM, the chip
may support Bluetooth, GPS, WLAN, WWAN or other transceivers, in
accordance with an embodiment of the invention. Referring to FIG.
2, there is shown the single chip 200 that may comprise a processor
system 202, a peripheral transport unit (PTU) 204, one or more
optional transceiver cores 205 and 206, a frequency modulation (FM)
core 208 with the FM transmitter 226 and the FM receiver 224
integrated into the FM core 208, and a common bus 201.
[0026] In this regard, the FM core 208 may support FM reception
and/or transmission of FM data. The FM transmitter 226 may utilize
signals based on the reference signal generated by the LO 227. The
FM core 208 may enable transmission of data received via the PTU
204 and/or a Bluetooth core 206, for example.
[0027] The processor system 202 may comprise a central processing
unit (CPU) 210, a memory 212, a direct memory access (DMA)
controller 214, a power management unit (PMU) 216, and an audio
processing unit (APU) 218. The APU 218 may comprise a sub-band
coding (SBC) codec 220. At least a portion of the components of the
processor system 202 may be communicatively coupled via the common
bus 201.
[0028] The CPU 210 may comprise suitable logic, circuitry, and/or
code that may enable control and/or management operations in the
single chip 200. In this regard, the CPU 210 may communicate
control and/or management operations to the optional transceiver
cores 205 and 206, the FM core 208, and/or the PTU 204 via a set of
register locations specified in a memory map. Moreover, the CPU 210
may be utilized to process data received by the single chip 200
and/or to process data to be transmitted by the single chip 200.
The CPU 210 may enable processing of data received via the optional
transceiver cores 205 and 206, via the FM core 208, and/or via the
PTU 204. For example, the CPU 210 may enable processing of A2DP
data and may then transfer the processed A2DP data to other
components of the single chip 200 via the common bus 201. In this
regard, the CPU may utilize the SBC codec 220 in the APU 218 to
encode and/or decode A2DP data, for example. The CPU 210 may enable
processing of data to be transmitted via the FM core 208, one or
more of the optional transceiver cores 205 and 206 and/or via the
PTU 204. The CPU 210 may be, for example, an ARM processor or
another embedded processor core that may be utilized in the
implementation of system-on-chip (SOC) architectures.
[0029] The CPU 210 may time multiplex FM data processing operations
and data processing operations from another integrated transceiver
such as Bluetooth for example. In this regard, the CPU 210 may
perform each operation by utilizing a native clock, that is,
Bluetooth data processing based on a Bluetooth clock and FM data
processing based on an FM clock. The Bluetooth clock and the FM
clock may be distinct and may not interact. The CPU 210 may gate
the FM clock and the Bluetooth clock and may select the appropriate
clock in accordance with the time multiplexing scheduling or
arrangement. When he CPU 210 switches between Bluetooth operations
and FM operations, at least certain states associated with the
Bluetooth operations or with the FM operations may be retained
until the CPU 210 switches back.
[0030] For example, in the case where the Bluetooth function is not
active and is not expected to be active for some time, the CPU 210
may run on a clock derived from the FM core 208. This may eliminate
the need to bring in a separate high-speed clock when one is
already available in the FM core 208. In the case where the
Bluetooth core 206 may be active, for example when the Bluetooth is
in a power-saving mode that requires it to be active periodically,
the processor may chose to use a clock derived separately from the
FM core 208. The clock may be derived directly from a crystal or
oscillator input to the Bluetooth core 206, or from a phase locked
loop (PLL) in the Bluetooth core 206. While this clocking scheme
may provide certain flexibility in the processing operations
performed by the CPU 210 in the single chip 200, other clocking
schemes may also be implemented.
[0031] The CPU 210 may also enable configuration of data routes to
and/or from the FM core 208. For example, the CPU 210 may configure
the FM core 208 so that data may be routed via an I.sup.2S
interface or a PCM interface in the PTU 204 to the analog ports
communicatively coupled to the PTU 204.
[0032] The CPU 210 may enable tuning, such as flexible tuning,
and/or searching operations in Bluetooth for example, and/or FM
communication by controlling at least a portion of the Bluetooth
core 206 and/or the FM core 208. For example, the CPU 210 may
generate at least one signal that tunes the FM core 208 to a
certain frequency to determine whether there is a station at that
frequency. When a station is found, the CPU 210 may configure a
path for the audio signal to be processed in the single chip 200.
When a station is not found, the CPU 210 may generate at least one
additional signal that tunes the FM core 208 to a different
frequency to determine whether a station may be found at the new
frequency.
[0033] Searching algorithms may enable the FM core 208 to scan up
or down in frequency from a presently tuned channel and stop on the
next channel with received signal strength indicator (RSSI) above a
threshold. The search algorithm may be able to distinguish image
channels. The choice of the IF frequency during search is such that
an image channel may have a nominal frequency error of 50 kHz,
which may be used to distinguish the image channel from the "on"
channel. The search algorithm may also be able to determine if a
high side or a low side injection provides better receive
performance, thereby allowing for a signal quality metric to be
developed for this purpose. One possibility to be investigated is
monitoring the high frequency RSSI relative to the total RSSI. The
IF may be chosen so that with the timing accuracy that a receiver
may be enabled to provide, the image channels may comprise a
frequency error that is sufficiently large to differentiate the
image channels from the on channel.
[0034] The CPU 210 may enable a host controller interface (HCI) in
Bluetooth. In this regard, the HCI provides a command interface to
the baseband controller and link manager, and access to hardware
status and control registers. The HCI may provide a method of
accessing the Bluetooth baseband capabilities that may be supported
by the CPU 210.
[0035] The memory 212 may comprise suitable logic, circuitry,
and/or code that may enable data storage. In this regard, the
memory 212 may be utilized to store data that may be utilized by
the processor system 202 to control and/or manage the operations of
the single chip 200. The memory 212 may also be utilized to store
data received by the single chip 200 via the PTU 204 and/or via the
FM core 208. Similarly, the memory 212 may be utilized to store
data to be transmitted by the single chip 200 via the PTU 204
and/or via the FM core 208. The DMA controller 214 may comprise
suitable logic, circuitry, and/or code that may enable transfer of
data directly to and from the memory 212 via the common bus 201
without involving the operations of the CPU 210.
[0036] The PTU 204 may comprise suitable logic, circuitry, and/or
code that may enable communication to and from the single chip 200
via a plurality of communication interfaces. In some instances, the
PTU 204 may be implemented outside the single chip 200, for
example. The PTU 204 may support analog and/or digital
communication with at least one port. Digital audio data may be
transferred by a digital interface, for example, inter-IC-sound
(I.sup.2S), inter-integrated circuit (I.sup.2C), pulse code
modulation (PCM), universal serial bus (USB), secure digital
input/output (SDIO) and/or universal asynchronous receiver
transmitter (UART). For example, the PTU 204 may support at least
one USB interface that may be utilized for Bluetooth data
communication, at least one SDIO interface that may also be
utilized for Bluetooth data communication, at least one UART
interface that may also be utilized for Bluetooth data
communication, and at least one inter-integrated circuit (I.sup.2C)
bus interface that may be utilized for FM control and/or FM and
RDS/RBDS data communication. The PTU 204 may also support at least
one PCM interface that may be utilized for Bluetooth data
communication and/or FM data communication, for example.
[0037] The PTU 204 may also support at least one inter-IC sound
(I.sup.2S) interface, for example. The I.sup.2S interface may be
utilized to send high fidelity FM digital signals to the CPU 210
for processing, for example. In this regard, the I.sup.2S interface
in the PTU 204 may receive data from the FM core 208 via a bus 203,
for example. Moreover, the I.sup.2S interface may be utilized to
transfer high fidelity audio in Bluetooth. For example, in the A2DP
specification there is support for wideband speech that utilizes 16
kHz of audio. In this regard, the I.sup.2S interface may be
utilized for Bluetooth high fidelity data communication and/or FM
high fidelity data communication. The I.sup.2S interface may be a
bidirectional interface and may be utilized to support
bidirectional communication between the PTU 204 and the FM core 208
via the bus 203. The I.sup.2S interface may be utilized to send and
receive FM data from external devices such as coder/decoders
(CODECs) and/or other devices that may further process the I.sup.2
S data for transmission, such as local transmission to speakers
and/or headsets and/or remote transmission over a cellular network,
for example.
[0038] The transceiver core 206 may for example be a Bluetooth core
and may comprise suitable logic, circuitry, and/or code that may
enable reception and/or transmission of Bluetooth data. The
Bluetooth core 206 may comprise a Bluetooth transceiver 229 that
may perform reception and/or transmission of Bluetooth data. In
this regard, the Bluetooth core 206 may support amplification,
filtering, modulation, and/or demodulation operations, for example.
The Bluetooth core 206 may enable data to be transferred from
and/or to the processor system 202, the PTU 204, and/or the FM core
208 via the common bus 201, for example.
[0039] The FM core 208 may comprise suitable logic, circuitry,
and/or code that may enable reception and/or transmission of FM
data. The FM core 208 may comprise an FM receiver 222, an FM
transmitter 226 and a local oscillator (LO) 227. The LO 227 may be
utilized to generate a reference signal that may be utilized by the
FM core 208 for performing analog and/or digital operations. The FM
receiver 222 may handle demodulation, amplification and/or
filtering operations, for example. The FM transmitter 226 may
handle modulation, amplification and/or filtering operations.
Moreover, the FM receiver 222 may receive FM audio data and
demodulate the audio data in a digital domain. The demodulated
digital audio data may be converted to analog via the D/A converter
224 and analog audio may be output from the chip to a listening
device. Also, analog audio may be input from an external device to
the FM transmitter 226. The FM transmitter 226 may comprise an
analog to digital converter (A/D) 228 that may be utilized to
convert analog audio information to a digital signal for modulation
in the digital domain prior to FM transmission. The FM core 208 may
enable data to be transferred to and/or from the processor system
202, the PTU 204, and/or one or more optional radio cores 206 via
the common bus 201 and/or the bus 203, for example.
[0040] The FM core 208 may enable radio transmission and/or
reception at various frequencies, such as, 400 MHz, 900 MHz, 2.4
GHz and/or 5.8 GHz, for example. The FM core 208 may also support
operations at the standard FM band comprising a range of about 76
MHz to 108 MHz, for example.
[0041] The FM core 208 may also enable reception of RDS data and/or
RBDS data for in-vehicle radio receivers. In this regard, the FM
core 208 may enable filtering, amplification, and/or demodulation
of the received RDS/RBDS data. The RDS/RBDS data may comprise, for
example, information for retuning to a new channel such as a
channel spacing offsets and a list of alternate channels available
for transmission. The RDS/RBDS may comprise a traffic message
channel (TMC) that provides traffic information that may be
communicated and/or displayed to an in-vehicle user.
[0042] Digital circuitry within the FM core 208 may be operated
based on a clock signal generated by dividing down a signal
generated by the LO 227. The LO 227 may be programmable in
accordance with the various channels that may be received by the FM
core 208 and the divide ratio may be varied in order to maintain
the digital clock signal close to a nominal value.
[0043] The RDS/RBDS data may be buffered in the memory 212 in the
processor system 202. The RDS/RBDS data may be transferred from the
memory 212 via the I.sup.2C interface when the CPU 210 is in a
sleep or stand-by mode. For example, the FM core 208 may post RDS
data into a buffer in the memory 212 until a certain level is
reached and an interrupt is generated to wake up the CPU 210 to
process the RDS/RBDS data. When the CPU 210 is not in a sleep mode,
the RDS data may be transferred to the memory 212 via the common
bus 201, for example.
[0044] Moreover, the RDS/RBDS data received via the FM core 208 may
be transferred to any of the ports communicatively coupled to the
PTU 204 via the HCI scheme supported by the single chip 200, for
example. The RDS/RBDS data may also be transferred to the
transceiver cores 205 and 206 for communication to
Bluetooth-enabled devices, for example.
[0045] In one exemplary embodiment of the invention, the single
chip 200 may receive Bluetooth data, such as A2DP, SCO, eSCO,
and/or MP3, for example, the Bluetooth core 206 may transfer the
received data to the processor system 202 via the common bus 201.
At the processor system 202, the SBC codec 220 may decode the
Bluetooth data and may transfer the decoded data to the FM core 208
via the common bus 201. The FM core 208 may transfer the data to
the FM transmitter 226 for communication to an FM receiver in
another device.
[0046] In another exemplary embodiment of the invention, the single
chip 200 may operate in a plurality of modes. For example, the
single chip 200 may operate in one of an FM-only mode, a
Bluetooth-only mode, and an FM-Bluetooth mode. For the FM-only
mode, the single chip 200 may operate with a lower power active
state than in the Bluetooth-only mode or the FM-Bluetooth mode
because FM operation in certain devices may have a limited source
of power. In this regard, during the FM-only mode, at least a
portion of the operation of the Bluetooth core 206 may be disabled
to reduce the amount of power used by the single chip 200.
Moreover, at least a portion of the processor system 202, such as
the CPU 210, for example, may operate based on a divided down clock
from a phase locked-loop (PLL) in the FM core 208. In this regard,
the PLL in the FM core 208 may utilize the LO 227, for example.
[0047] Moreover, because the code necessary to perform certain FM
operations, such as tuning and/or searching, for example, may only
require the execution of a few instructions in between time
intervals of, for example, 10 ms, the CPU 210 may be placed on a
stand-by or sleep mode to reduce power consumption until the next
set of instructions is to be executed. In this regard, each set of
instructions in the FM operations code may be referred to as a
fragment or atomic sequence. The fragments may be selected or
partitioned in a very structured manner to optimize the power
consumption of the single chip 200 during FM-only mode operation.
In some instances, fragmentation may also be implemented in the
FM-Bluetooth mode to enable the CPU 210 to provide more processing
power to Bluetooth operations when the FM core 208 is carrying out
tuning and/or searching operations, for example.
[0048] FIG. 3 is a block diagram of an exemplary FM core with FM
transmitter and PTU for processing RDS and digital audio data, in
accordance with an embodiment of the invention. Referring to FIG.
3, there is shown a portion of a single chip 200 from FIG. 2,
comprising an FM core 208, a memory 212, a CPU 210, a common bus
201. Also shown are portions of a PTU which may comprise an
interface multiplexer 310, a universal peripheral interface (UPI)
304, a bus master interface 302, a digital audio interface
controller 306, an I.sup.2S interface block 308, and an I.sup.2C
interface block 312.
[0049] The FM core 208 may comprise an FM/MPX demodulator and
decoder 317, an FM/MPX modulator and encoder 317a, rate adaptors
314 and 314a, a buffer 316, an RDS/RBDS demodulator and decoder
318, a RDS/RBDS modulator and encoder 318a, and a control registers
block 322. Narrowly spaced hashed arrows as illustrated by the flow
arrow 332 show the flow of digital audio data. Broadly spaced
hashed arrows as illustrated by the flow arrow 334 show the flow of
RDS/RBDS data. Clear or blank arrows, as illustrated by the dual
flow arrow 336, show the flow of control data.
[0050] The FM/MPX demodulator and decoder 317 may comprise suitable
logic, circuitry, and/or code that may enable processing of FM
and/or FM MPX stereo audio, for example. The FM/MPX demodulator and
decoder 317 may demodulate and/or decode audio signals that may be
transferred to the rate adaptor 314. The FM/MPX demodulator and
decoder 317 may demodulate and/or decode signals that may be
transferred to the RDS/RBDS demodulator and decoder 318.
[0051] The FM/MPX encoder 317a may comprise suitable logic,
circuitry, and/or code that may enable processing of FM and/or FM
MPX stereo audio, for example. The FM/MPX encoder 317a may encode
audio signals that may be transferred from the rate adaptor 314a.
The FM/MPX encoder 317a may encode signals that may be transferred
to the RDS/RBDS modulator and encoder 318a.
[0052] The rate adaptors 314 and 314a may comprise suitable logic,
circuitry, and/or code that may enable controlling the rate of the
FM data received from the FM/MPX demodulator and decoder 317. The
rate adaptors 314 and 314a may adapt the output sampling rate of
the audio paths to the sampling clock of the host device or the
rate of a remote device when a digital audio interface is used to
transport the FM data. An initial rough estimate of the adaptation
fractional change may be made and the estimate may then be refined
by monitoring the ratio of reading and writing rates and/or by
monitoring the level of the audio samples in the output buffer. The
rate may be adjusted in a feedback manner such that the level of
the output buffer is maintained. The rate adaptors 314 and 314a may
receive a strobe or pull signal from the digital audio interface
controller 306, for example. Audio FM data from the rate adaptors
314 and 314a may be transferred to the buffer 316. The U.S.
application Ser. No. 11/176,417 filed on Jul. 7, 2005, discloses a
method and system comprising a rate adaptor, and is hereby
incorporated herein by reference in its entirety.
[0053] The buffer 316 may comprise suitable logic, circuitry,
and/or code that may enable storage of digital audio data. The
buffer 316 may receive a strobe or pull signal from the digital
audio interface controller 306, for example. The buffer 316 may
transfer digital audio data to the digital audio interface
controller 306.
[0054] The RDS/RBDS demodulator and decoder 318 may comprise
suitable logic, circuitry, and/or code that may enable processing
of RDS/RBDS data from the FM/MPX demodulator and decoder 317. The
RDS/RBDS demodulator and decoder 318 may provide further
demodulation and/or decoding to data received from the FM/MPX
demodulator and decoder 317. The output of the RDS/RBDS
demodulator, and decoder 318 may be transferred to the interface
multiplexer 310.
[0055] The RDS/RBDS modulator and encoder 318a may comprise
suitable logic, circuitry, and/or code that may enable processing
of RDS/RBDS data from the FM/MPX modulator and encoder 317a. The
RDS/RBDS modulator and encoder 318a may provide further modulation
and/or encoding to data received from the FM/MPX modulator and
encoder 317. The output of the RDS/RBDS modulator and encoder 318
may be transferred to the interface multiplexer 310.
[0056] The control registers block 322 may comprise suitable logic,
circuitry, and/or code that may enable the storage of register
information that may be utilized to control and/or configure the
operation of at least portions of the FM core 208.
[0057] In operation, the FM core 208 may enable radio transmission
and/or reception at various frequencies, such as, 400 MHz, 900 MHz,
2.4 GHz and/or 5.8 GHz, for example. The FM core 208 may also
support operations at the standard FM band comprising a range of
about 76 MHz to 108 MHz, for example. The FM core 208 may also
enable reception of RDS data and/or RBDS data for in-vehicle radio
receivers. In this regard, the FM core 208 may enable filtering,
amplification, and/or demodulation of the received RDS/RBDS data.
The RDS/RBDS data may comprise, for example, a traffic message
channel (TMC) that provides traffic information that may be
communicated and/or displayed to an in-vehicle user.
[0058] The memory 212 may comprise suitable logic, circuitry,
and/or code that may enable data storage. In this regard, the
memory 212 may be utilized to store data that may be utilized by
the CPU 210 to control and/or manage the operations of the single
chip 200. The memory 212 may also be utilized to store data
received by the single chip 200 via the FM core 208. Similarly, the
memory 212 may be utilized to store data to be transmitted by the
single chip 200 via the FM core 208.
[0059] The CPU 210 may comprise suitable logic, circuitry, and/or
code that may enable control and/or management operations in the
single chip 200. In this regard, the CPU 210 may communicate
control and/or management operations to the FM core 208 via a set
of register locations specified in a memory map. Moreover, the CPU
210 may be utilized to process data received by the single chip 200
and/or to process data to be transmitted by the single chip 200.
The CPU 210 may enable processing of data received the FM core 208.
For example, the CPU 210 may enable processing of A2DP data and may
then transfer the processed A2DP data to other components of the
single chip 200 via the common bus 201. In this regard, the CPU may
utilize the SBC codec 220 in the APU 218 to encode and/or decode
A2DP data, for example. The CPU 210 may enable processing of data
to be transmitted via the FM core 208. The CPU 210 may be, for
example, an ARM processor or another embedded processor core that
may be utilized in the implementation of system-on-chip (SOC)
architectures.
[0060] The CPU 210 may also enable configuration of data routes to
and/or from the FM core 208. For example, the CPU 210 may configure
the FM core 208 so that data may be routed via an I.sup.2S
interface or a PCM interface.
[0061] The CPU 210 may enable tuning, such as flexible tuning,
and/or searching operations in FM communication by controlling at
least a portion of the FM core 208. For example, the CPU 210 may
generate at least one signal that tunes the FM core 208 to a
certain frequency to determine whether there is a station at that
frequency. When a station is not found, and interference is below a
specified threshold, the CPU 210 may configure a path for the audio
signal to be transmitted in the single chip 200. When a station is
found with RSSI above a specified threshold, the CPU 210 may
generate at least one additional signal that tunes the FM core 208
to a different frequency to determine whether a channel may be
clear for transmission at the new frequency. The CPU 210 may create
a list of available channels for FM transmission and rank the list
according to lowest receive signal strength indicator (RSSI) and
other factors for improved channel searching times.
[0062] The bus master interface 302 may comprise suitable logic,
circuitry, and/or code that may enable communication of control
data, digital audio data, and/or RDS/RBDS data between the portions
of the PTU 204 shown in FIG. 2 and the common bus 201. The bus
master interface 302 may transfer digital audio data and/or
RDS/RBDS data to the common bus 201. The RDS/RBDS data may be
transferred to the memory 212, for example. In some instances, the
RDS/RBDS data may be transferred to the memory 212 when the CPU 210
is in a stand-by or sleep mode. The bus master interface 302 may
push RDS/RBDS data into a buffer in the memory 212 or may pull
RDS/RBDS data from a buffer in the memory 212, for example. The
digital audio data may be transferred to the CPU 210 for
processing, for example. The CPU 210 may generate and/or receive
control data that may be communicated with the PTU 204 and/or the
FM core 208 via the common bus 201.
[0063] The UPI 304 may comprise suitable logic, circuitry, and/or
code that may enable the transfer of RDS/RBDS data to the bus
master interface 302 from the interface multiplexer 310. The UPI
304 may also enable the communication of control data between the
bus master interface 302 and the interface multiplexer 310.
[0064] The digital audio interface controller 306 may comprise
suitable logic, circuitry, and/or code that may enable the transfer
of digital audio data to the bus master interface 302 and/or the
I.sup.2S interface block 308. The I.sup.2S interface 308 may
comprise suitable logic, circuitry, and/or code that may enable
transfer of the digital audio data to at least one device
communicatively coupled to the single chip. The I.sup.2S interface
308 may communicate control data with the bus master interface
302.
[0065] The I.sup.2C interface 308 may comprise suitable logic,
circuitry, and/or code that may enable transfer of the RDS/RBDS
data to at least one device communicatively coupled to the single
chip. The I.sup.2C interface 308 may also communicate control data
between external devices to the single chip and the interface
multiplexer 310. In this regard, the interface multiplexer 310 may
communicate control data between the I.sup.2C interface 308, the
UPI 304, and/or the control registers block 322 in the FM core
208.
[0066] The interface multiplexer 310 may comprise suitable logic,
circuitry, and/or code that may enable the transfer of RDS/RBDS
data to the UPI 304 and/or the I.sup.2C interface block 312. In
this regard, the UPI 304 may generate a signal that indicates to
the interface multiplexer 310 the interface to select.
[0067] The I.sup.2C interface 312 may comprise suitable logic,
circuitry, and/or code that may enable transfer of the RDS/RBDS
data to at least one device communicatively coupled to the single
chip. The I.sup.2C interface 312 may also communicate control data
between external devices to the single chip and the interface
multiplexer 310. In this regard, the interface multiplexer 310 may
communicate control data between the I.sup.2C interface 312, the
UPI 304, and/or the control registers block 322 in the FM core
208.
[0068] FIG. 4A is a flow chart for an exemplary algorithm that
enables determining channel spacing offsets when RDS/RBDS data and
user input are not available, in accordance with an embodiment of
the invention. Information regarding found channels which may
comprise channel frequencies, offsets between frequencies, received
signal strength indicator (RSSI) and/or carrier error for example,
may be determined and recorded in a database, in accordance with an
embodiment of the invention. The database may be utilized during
channel scanning or search operations to improve the scan or search
time.
[0069] Referring to FIG. 4A, there is shown the flow diagram. After
start 468, in step 470, scanning may begin at the low end of the
band, a current channel or at a programmed start point. In step
470, RSSI and carrier error may be recorded for a first channel
found. In step 474, in instances where the RSSI may be above a
specified threshold and carrier error may be below a specified
threshold, the exemplary steps may proceed to step 476. In step
476, tuning to this channel may occur. Additionally, in step 476,
channel information may be recorded and it may be noted whether the
least significant byte (LSB) is odd or even. In step 478, if the
band edge has been reached, the exemplary steps may proceed to
proceed to step 480. In step 480, the list of channels in the
database may be reviewed. In step 482, if the number of odd
channels and the number of even channels recorded are close, for
example if one is within a multiple of twenty, of the other, the
exemplary steps may proceed to step 484. In step 484, a frequency
offset between channels of, for example, 100 kHz may be determined.
The exemplary steps may proceed to end step 486.
[0070] In step 474, if the RSSI recorded in step 472 was below a
specified threshold, and/or the carrier error recorded was above a
specified threshold, the exemplary steps may proceed to step 488.
In step 488, if the edge of the scanning band has not been reached,
proceed to step 490. In step 490, the frequency may be increased
until the next step is reached. Tuning to a channel may occur and
the exemplary steps may proceed to step 472. In step 488, if the
edge of the scanning band has been reached, the exemplary steps may
proceed to step 480 as indicated by marker A.
[0071] In step 482, if the number of odd channels and the number of
even channels are not close, the exemplary steps may proceed to
step 492. In step 492, if the number of odd channels is much
greater than the number of even channels, for example, if the
number of odd channels is at least twenty times greater then number
of even channels, the exemplary steps may proceed to step 494. In
step 494, it may be determined that the FM channels may have, for
example, a 200 kHz spacing between channel frequencies and use odd
numbered frequencies. For example in one location, channels may
occur at 99.1 MHz, 99.3 MHz, 99.5 MHz, etc.). The exemplary steps
may proceed to 486.
[0072] In step 492, if the number of even channels is much greater
than the number of odd channels, for example, if the number of even
channels is at least twenty times greater then number of odd
channels, proceed to step 494. In step 494, it may be determined
that the FM channels may have, for example, a 200 kHz spacing
between channel frequencies and use even numbered frequencies. For
example in one location, channels may occur at 99.2 MHz, 99.4 MHz,
99.6 MHz, etc.). The exemplary steps may proceed to 486.
[0073] For future scans, if a FM channel frequency offset or
frequency spacing between channels has been determined prior to
scan operations, the scan algorithm may use a known frequency
offset to jump between FM channel frequencies. If no channels are
found when reaching a scanning band edge in a scan that presumed
one type of offset, a second scan through the scanning spectrum may
utilize an alternate frequency offset before stopping.
[0074] FIG. 4B is a block diagram of a plurality of exemplary radio
devices that enable frequency modulation (FM) transmission and
reception, in accordance with an embodiment of the invention.
Referring to FIG. 4B, there is shown an FM receiver device 410
comprising a speaker 412, a processor 414, a visual display 416, a
user input interface 418, a memory 420, an FM radio receiver 422
and an optional alternate technology transmitter and receiver 424.
The device 430 may comprise a speaker 432, a processor 434, an FM
radio transmitter and FM radio receiver 436, an optional alternate
technology transmitter and receiver 438, a display 440, a user
input interface 442, a memory 444 and an optional global
positioning system (GPS) receiver 446.
[0075] The FM receiver device 410 may comprise suitable logic,
circuitry and/or code to receive signals within the FM frequency
band and may for example be a car radio, home stereo system or
computer system. The FM receiver device 410 may demodulate and
decode audio signals as well as Radio Data System (RDS) and/or
Radio Broadcast Data System (RBDS) signals. In this regard the FM
receiver device may store RDS data as well as FM channel candidate
information for quicker scanning of available FM channels. The FM
receiver device 410 may process RDS/RBDS signals and tune to an FM
channel based on RDS/RBDS information channel selection algorithms.
The FM receiver device 410 may be capable of receiving manual input
from a user such as channel selection. It may also display
information for the user with regard to channel selection and
RDS/RBDS data.
[0076] The speaker or listening device 412 may be suitable for
converting electrical output from the receiver device to
appropriate audio acoustical waves for a listener. The speaker may
also output text to speech (TTS) information for the listener. For
example, TTS may enable alerting a user to conditions that require
input from the user such as selecting a channel and/or
configuration modifications. The speaker or listening device may be
communicatively coupled with the processor 414.
[0077] The processor 414 may comprise suitable logic, circuitry
and/or code that may enable management of scanning, detecting and
tuning operations based on a plurality of inputs comprising user
input, RDS/RBDS or GPS data such as location information, RSSI
levels, carrier error, programmed algorithms and a candidate
channel database received from the transceiver device 430. The
processor 414 may create a list of available channels for FM
reception and rank the list according to lowest receive signal
strength indicator (RSSI) and other factors for improved channel
searching times. The processor 414 may also be enabled to process
audio data. The processor 414 may be communicatively coupled with
the FM radio receiver 422, the memory 420, the display 416 and the
speaker or listening device 412.
[0078] The display 416 may comprise suitable logic, circuitry
and/or code to display visual information for the user. The
receiver device 410 may display operational conditions of the
device, selected FM channel information and RDS/RBDS information.
The visual display may be utilized to inform a user when input may
be needed such as selecting an FM channel or making a configuration
modification. The display 416 may be communicatively coupled with
the processor 414 and the memory 420.
[0079] The user input interface 418 may comprise a suitable
interface for manual input of information that may be utilized by
the receiver device 410 to make channel selections or input
configuration parameters. The user input may comprise a voice
recognition system where input may be spoken by a user and
converted to digital information for use as parameters in receiver
device 410 operations.
[0080] The memory 420 may comprise suitable logic, circuitry and/or
code to store and retrieve information that supports scanning,
detecting and tuning operations within the receiver device 410. The
memory 420 may store: user input, RDS/RBDS or GPS data such as
location information, RSSI levels, carrier error, programmed
algorithms and a channel database received from the transceiver
device 430. The memory 420 may store information that maps FM
channels and locally regulated operating constraints, to geographic
or market areas in a plurality of continents around the world. The
memory 420 may store audio data as well.
[0081] The FM radio receiver 422 may comprise suitable logic,
circuitry and/or code to demodulate and decode FM signals
comprising at least audio and RDS/RBDS information. The FM radio
receiver 422 may be coupled with one or more antennas and may
receive transmissions from the transceiver device 430, make
measurements of the FM spectrum, for example RSSI levels and
carrier error, which may be utilized for scanning, detecting and
tuning operations and, receive. The FM radio receiver 422 may
comprise filters and amplifiers that are designed to adapt to RF
signals conditioned and transmitted from the transceiver device 430
according to local regulations regarding pre-emphasis time
constants and transmit (TX) power levels. The FM radio receiver 422
may be communicatively coupled with the processor 414, the memory
420, and an FM antenna 426. If the receiver device 410 comprises an
alternate technology transmitter and receiver 424, for example a
Bluetooth or wireless local area network (WLAN) receiver, the FM
radio receiver 422 and alternate technology transmitter and
receiver 424 may each have their own antenna or may share a wide
band or dual band antenna. In this regard, the FM radio receiver
422 and the alternate band transmitter and/or receiver signals may
be decoupled in a diplexer and/or duplexer between the receivers
and shared antenna 426. Additional optional alternate technology
transceivers may share antennas in a similar manner.
[0082] The alternate technology transmitter and receiver 424 may be
optional and may facilitate operations regarding one or more
embodiments of the invention. The alternate technology transmitter
and receiver 424 may comprise one or more of a plurality of radio
technologies which may be for example, Bluetooth, WLAN, WWAN, RFID,
infrared or a wire-line connection. The receiver portion of the
alternate technology transmitter and receiver 424 may receive
information from the transmitter portion of the alternate
technology transmitter and receiver 438 on transceiver device 430
with regard to location, configuration or FM channel selection
operations. In this regard, a new FM channel for re-tuning may be
transmitted or a candidate channel database comprising one or more
channels and information regarding channel selection and/or
configuration.
[0083] In addition, information regarding location, configuration
and/or FM channel selection operations may be transmitted from the
transmitter portion of the alternate technology transmitter and
receiver 424 on the receiver device 410 to the receiver portion of
the alternate technology transmitter and receiver 438 on
transceiver device 430. The alternate technology transmitter and
receiver 424 may be communicatively coupled with the processor 414,
the memory 420 and an antenna. The alternate technology transmitter
and receiver 424 may utilize a simplex or duplex antenna. The
alternate technology transmitter and receiver 424 and the FM radio
receiver 422 may each have their own antenna or may share a wide
band or dual band antenna. In this regard, the FM radio receiver
422 signals and the alternate band transmitter and/or receiver
signals may be decoupled in a diplexer and/or duplexer between the
receivers and shared antenna 426. Additional optional alternate
technology transmitters and receivers may share antennas in a
similar manner.
[0084] The FM transceiver device 430 may comprise suitable logic,
circuitry and/or code to receive and transmit signals within the FM
frequency band and may for example be a handheld or portable
device. For example the FM transceiver device 430 may be an MP3
player or another content rendering device, a laptop or a wireless
phone. The FM transceiver device 430 may handle
modulation/demodulation and code/decode operations for audio
signals as well as Radio Data System (RDS) and/or Radio Broadcast
Data System (RBDS) signals. In this regard the FM transceiver
device 430 may store RDS data as well as FM channel candidate
information for quicker scanning of available FM channels.
[0085] The FM transceiver device 430 may process RDS/RBDS signals
and tune to an FM channel based on RDS/RBDS information channel
selection algorithms. The FM transceiver device 430 may be capable
of receiving manual input from a user such as channel selection. It
may also display information for the user with regard to channel
selection, RDS/RBDS data, and/or transmitter configuration
information. In addition information regarding channel selection
for retuning operations may be communicated from the FM transceiver
device 430 to the FM receiver device 410 in a plurality of
ways.
[0086] The speaker or listening device 432 may be suitable for
converting electrical output from the receiver device to
appropriate audio acoustical waves for a listener. The speaker may
also output text to speech (TTS) information for the listener. For
example, TTS may enable alerting a user to conditions that require
input from the user such as selecting a channel or transmitter
configuration modifications. The speaker or listening device may be
communicatively coupled with the processor 434.
[0087] The processor 434 may comprise suitable logic, circuitry
and/or code that may enable management of scanning, detecting and
tuning operations based on a plurality of inputs comprising user
input, RDS/RBDS or GPS data such as location information, RSSI
levels, carrier error, programmed algorithms and a candidate
channel database stored in memory 444. The processor 444 may create
a list of available channels for FM transmission and rank the list
according to, for example, lowest receive signal strength indicator
(RSSI) and other factors for improved channel searching times.
Other ranking criteria may be utilized. The processor 434 may
process audio data as well. The processor 434 may be
communicatively coupled with the FM radio transmitter and FM radio
receiver 436, the memory 444, the display 449 and the speaker or
listening device 432.
[0088] The display 440 may comprise suitable logic, circuitry
and/or code to display visual information for the user. The
transceiver device 430 may display operational conditions of the
device, selected FM channel information and RDS/RBDS information.
The visual display may be utilized to inform a user when input may
be needed such as selecting an FM channel or making a configuration
modification. The display 440 may be communicatively coupled with
the processor 434 and the memory 444.
[0089] The User input interface 442 may comprise a suitable
interface for manual input of information that may be utilized by
the transceiver device 430 to make channel selections or input
configuration parameters. The user input may comprise a voice
recognition system wherein input may be spoken by a user and
converted to digital information for use as parameters in
transceiver device 430 operations.
[0090] The memory 444 may comprise suitable logic, circuitry and/or
code to store and retrieve information that supports scanning,
detecting and turning operations within the transceiver device 430.
The memory 444 may store: user input, RDS/RBDS or GPS data such as
location information, RSSI levels, carrier error, programmed
algorithms and a candidate channel database. The memory 444 may
store information that maps FM channels and locally regulated
transmitter configuration parameters such as filter time constants
and transmit power level constraints, to geographic or market areas
in a plurality of continents around the world. The memory 444 may
store audio data as well.
[0091] The FM radio transmitter and FM radio receiver 436 may
comprise suitable logic, circuitry and/or code to
modulate/demodulate and code/decode FM signals comprising at least
audio and RDS/RBDS information. The FM radio transmitter and FM
radio receiver 436 may be coupled with one or more antennas for
transmission to the receiver device 410 and, to make measurements
of the FM spectrum, for example RSSI levels and carrier error,
which may be utilized for scanning, detecting and tuning
operations. The FM radio transmitter and FM radio receiver 436 may
be utilized for transmitting and receiving a plurality of other
signals. The FM radio receiver 422 may comprise filters and
amplifiers that may be configured to condition RF signals according
to local regulations which may for example comprise pre-emphasis
time constants and transmit (TX) power levels.
[0092] The FM radio transmitter and FM radio receiver 436 may be
communicatively coupled with the processor 434, the memory 444, and
one or more FM antennas 448. If the transceiver device 430
comprises an optional alternate technology transmitter and receiver
438, for example a Bluetooth or wireless local area network (WLAN)
transmitter receiver, the FM transmitter receiver and alternate
technology transmitter receiver may each have their own antennas
which may be duplex or simplex, or, they may share wide band or
dual band antennas. In this regard, the FM radio transmitter and FM
radio receiver 436 input and the alternate technology transmitter
and receiver 438 input may be coupled in a diplexer between the FM
radio transmitter and FM radio receivers 436 and, the alternate
technology transmitter and receiver 438, and the shared the antenna
448. Additional optional alternate technology transmitter receivers
may share antennas in a similar manner.
[0093] The alternate technology transmitter receiver 448 may be
optional and may facilitate operations regarding one or more
embodiments of the invention. The alternate technology may comprise
one or more of a plurality of radio technologies which may be for
example, Bluetooth, WLAN, WWAN, RFID, infrared or simply a
wire-line connection. The alternate technology transmitter and
receiver 448 may transmit information to the alternate technology
transmitter and receiver 424 on receiver device 410 with regard to
location, configuration and/or channel selection operations. In
this regard, a new FM channel for re-tuning may be transmitted or a
database comprising one or more channels and information regarding
channel selection may be transmitted to the alternate technology
transmitter and receiver 424.
[0094] In addition, alternate technology receiver 448 on FM
receiver device 430 may receive information from the transmitter
portion of the alternate technology transmitter and receiver 424 on
FM receiver device 410 regarding location, configuration and/or
channel selection operations. The alternate technology transmitter
and receiver 438 may be communicatively coupled with the processor
434, the memory 444 and an antenna 448. The alternate technology
transmitter and receiver 438 and the FM radio transmitter and FM
radio receiver 436 may each have their own antennas which may be
duplex or simplex, and/or, they may share wide band or dual band
antennas. In this regard, the FM radio transmitter and FM radio
receiver 436 signals and the alternate technology transmitter and
receiver 438 signals may be decoupled in a diplexer between the FM
radio transmitter and FM radio receiver 436, and the alternate
technology transmitter and receiver 438, and shared the antenna
448. Any additional optional alternate technology transmitters and
receivers may share antennas in a similar manner.
[0095] In operation, the transceiver device 430 in FIG. 4B may be
for example, a handheld device such as an MP3 player or another
digital music format player, equipped with an FM radio. The
receiver device 410 may be an FM radio, for example a car radio or
home stereo system. The transceiver device 430 may transmit an
audio signal via an FM channel to the receiver device 410 and the
receiver device may demodulate the FM signal and amplify the
acoustical audio output over a speaker or listening device 412.
[0096] A channel suitable for transmission from the FM transceiver
device 430 to the FM receiver device 410 may be chosen based on a
plurality of criteria and in a plurality of ways. For example,
channels within a local FM frequency band may be scanned and
measured for received signal strength (RSSI) and carrier frequency
error. A list of channels which are candidates for FM transmission
may be compiled and utilized in future scans or channel searches to
improve the scan or search time by one or both of the FM devices. A
channel selected for transmission may be auto-determined by one or
both of the FM devices or, a user may assist in the selection of a
channel by providing input via a user interface on one or both of
the devices.
[0097] In this regard, a scan function within the FM transceiver
430 and/or the FM receiver 410, may increment a local oscillator in
specified frequency steps. Step size may vary depending frequency
offsets between FM channels. Frequency offsets are determined by
government regulations for a country or location of FM operations.
Different countries specify different offsets between FM channels.
Offsets could be for example, 50 kHz, 100 kHz or 200 kHz. When the
frequency offset and best size scan step are known prior to
scanning operations, the time duration for scanning, detecting and
selecting FM channels may be improved.
[0098] In addition, the FM transceiver device 430 may determine
configuration parameters for FM transmissions based on government
regulations for the country or location of operation. For example,
specified maximum transmit power and pre-emphasis time constants
for transmit filters may vary by country or location.
[0099] The memory 444 within FM transceiver device 430 and/or the
memory 420 within receiver device 410 may comprise one or more
databases that map for example, FM channels, frequency offsets and
configuration parameters to geographic location. Such mappings may
assist in improving time for channel scanning and transmitter
configuration.
[0100] The FM transceiver device 430 may auto-determine its
location or may be assisted by input from a user in order to
identify channel spacing and to configure components for
transmission according to local government regulations. Location
information, channel spacing and/or configuration parameters may be
input during setup of the transceiver device 430 and stored for
future use.
[0101] In one embodiment of the invention, the FM transceiver
device 430 may prompt a user for input of geographic location or
configuration parameters via visual display 440 for example or via
audible communication utilizing text to speech (TTS) technology and
the listening device 432. In this regard, the user may input their
location or configuration parameters by keying in text or by
indicating with voice via the user input interface 442.
[0102] In another embodiment of the invention, the FM transceiver
device 430 may determine its location via Radio Data System (RDS)
or Radio Broadcast Data System (RBDS) information received from an
FM host system in the country of operation. In this regard, the FM
transceiver device 430 may detect an active channel and demodulate
and decode the RDS/RBDS signal. The RDS/RBDS information may
provide a country code and/or location code that may be utilized to
search for channel offsets and configuration parameters within the
database of memory 444. In another embodiment of the invention, the
FM transceiver device 430 may comprise a global positioning system
(GPS) receiver that may enable the device to determine its location
from received GPS data.
[0103] If RDS/RBDS and user input information is not available and
the location of operation is unknown, the FM transceiver device 430
may auto-determine the frequency offset between FM channels by
scanning frequency spectrum and, based upon channels found,
determine optimum parameters to use for future or remaining scan
activities as illustrated in the flow chart of FIG. 4A. A database
may be populated comprising found FM channel information in order
to improve future scanning and detecting times.
[0104] Once the frequency spacing between FM channels is known, an
FM channel with low interference may be selected for FM
transmissions to the receiver device 410. The FM transceiver device
430 may jump by known frequency offsets to FM channels and measure
RSSI and carrier error on the channels. The FM transceiver device
430 may select a channel on a plurality of criteria. For example,
it may select a channel with the lowest RSSI. In another embodiment
of the invention, the FM transceiver device may select a channel
with an RSSI below a specified threshold and a history of the
longest duration of an RSSI below a specified threshold.
[0105] Once a channel is selected by the FM transceiver device 430,
it may be communicated in a plurality of ways to the FM receiver
410. In one embodiment of the invention, a user may intervene to
set a channel on the FM receiver 410. For example, once the FM
transceiver device 430 has selected an FM channel for transmission,
the selected channel may be displayed on the display 440 or
indicated in an audible alert to the user utilizing text to speech
via the speaker or listening device 432. The user may then set the
selected channel on the FM receiver 410 utilizing a keying input or
voice instruction via the user input interface 418. In another
embodiment of the invention, the selected channel number may be
communicated to the FM receiver via an FM channel, a sideband or
via an alternate technology frequency band such as Bluetooth or
WLAN for example or WLAN. In this regard, the FM receiver 410 may
display the selected channel on the display 416 or indicate the
selected channel in an audible alert to the user utilizing text to
speech via the speaker or listening device 412. The user may then
set the selected channel on the FM receiver 410 utilizing a keying
input or voice instruction via the user input interface 418.
[0106] In another embodiment of the invention, the re-tuning
process may take place autonomously, without user intervention. For
example, the FM transceiver device 430 and the FM receiver device
410 may both go into a scanning mode and update and rank their
channel candidate lists which may be very similar to each other due
to their close proximity within a radio frequency (RF) environment.
In this regard the scanning mode may be initiated by user input or
initiated dynamically for example, via RDS/RBDS transmission on the
FM channel to the FM receiver device 410. In addition, information
may be sent to the FM receiver device 410 on a sideband or on an
alternate technology frequency band for example, Bluetooth, WLAN,
WWAN and/or on a wire-line. Moreover, the FM receiver device 410
may provide information to the FM transceiver device 430, regarding
location, configuration preferences or FM channels via the
alternate technology transmitter and receiver 424 and alternate
technology transmitter and receiver 438.
[0107] In an exemplary embodiment of the invention, the FM
transceiver device 430 may update its channel candidate list and
transmit it to the FM receiver device 410 via RDS/RBDS, a side band
or via another frequency band such as Bluetooth, WLAN, WWAN or a
wire-line. Once both FM devices comprise the same or similar ranked
channel candidate lists, the FM transceiver device 430 may select a
channel from its channel candidate list and begin to transmit an FM
signal on it. The FM receiver device 410 may search for the
strongest signal on its list and re-tune to the new channel
[0108] In an embodiment of the invention, the FM radio transmitter
and FM radio receiver in block 430 disclosed in FIG. 4B may be an
integrated circuit in an end user portable or mobile communication
device that enables determining of geographic location and FM
channel map and configuring the FM transmitter based on the channel
map. The channel map may comprise a list of ranked FM channels. The
FM receiver may acquire geographic location from a plurality of
sources comprising radio data system (RDS) or Radio Broadcast Data
System (RBDS) signals, Global Position System (GPS) data via an
integrated GPS receiver on the mobile device, from wireless or
wire-line network data via an integrated receiver on the mobile
device and/or from user data. The FM radio transmitter and FM radio
receiver in block 430, may determine channel spacing, channel
offset and/or frequency band for the FM channel map. A frequency
for transmitting FM signals may be selected based on the FM channel
map. In addition, the FM radio receiver and/or FM radio transmitter
may be configured based on information from an in-band FM signal or
an out-of-band signal and the FM channel map. The out-of-band
signal may comprise one or more of a Bluetooth signal, a WLAN
signal, a ZigBee signal and a wireless signal. An audio or visual
signal may be generated that indicates a channel being used by the
FM radio transmitter. The audio signal may text to speech
translation and/or one or more audible tones.
[0109] Certain embodiments of the invention may comprise a
machine-readable storage having stored thereon, a computer program
having at least one code section for determining channel spacing
and configuring an FM transmitter, the at least one code section
being executable by a machine for causing the machine to perform
one or more of the steps described herein.
[0110] Accordingly, aspects of the invention may be realized in
hardware, software, firmware or a combination thereof. The
invention may be realized in a centralized fashion in at least one
computer system or in a distributed fashion where different
elements are spread across several interconnected computer systems.
Any kind of computer system or other apparatus adapted for carrying
out the methods described herein is suited. A typical combination
of hardware, software and firmware may be a general-purpose
computer system with a computer program that, when being loaded and
executed, controls the computer system such that it carries out the
methods described herein.
[0111] One embodiment of the present invention may be implemented
as a board level product, as a single chip, application specific
integrated circuit (ASIC), or with varying levels integrated on a
single chip with other portions of the system as separate
components. The degree of integration of the system will primarily
be determined by speed and cost considerations. Because of the
sophisticated nature of modern processors, it is possible to
utilize a commercially available processor, which may be
implemented external to an ASIC implementation of the present
system. Alternatively, if the processor is available as an ASIC
core or logic block, then the commercially available processor may
be implemented as part of an ASIC device with various functions
implemented as firmware.
[0112] The present invention may also be embedded in a computer
program product, which comprises all the features enabling the
implementation of the methods described herein, and which when
loaded in a computer system is able to carry out these methods.
Computer program in the present context may mean, for example, any
expression, in any language, code or notation, of a set of
instructions intended to cause a system having an information
processing capability to perform a particular function either
directly or after either or both of the following: a) conversion to
another language, code or notation; b) reproduction in a different
material form. However, other meanings of computer program within
the understanding of those skilled in the art are also contemplated
by the present invention.
[0113] While the invention has been described with reference to
certain embodiments, it will be understood by those skilled in the
art that various changes may be made and equivalents may be
substituted without departing from the scope of the present
invention. In addition, many modifications may be made to adapt a
particular situation or material to the teachings of the present
invention without departing from its scope. Therefore, it is
intended that the present invention not be limited to the
particular embodiments disclosed, but that the present invention
will include all embodiments falling within the scope of the
appended claims.
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