U.S. patent number RE44,551 [Application Number 13/645,471] was granted by the patent office on 2013-10-22 for universal tuner for mobile tv.
This patent grant is currently assigned to Newport Media, Inc.. The grantee listed for this patent is Mohy Abdelgany, Frank Carr, Hassan Elwan, Amr Fahim, Edward Youssoufian. Invention is credited to Mohy Abdelgany, Frank Carr, Hassan Elwan, Amr Fahim, Edward Youssoufian.
United States Patent |
RE44,551 |
Abdelgany , et al. |
October 22, 2013 |
Universal tuner for mobile TV
Abstract
A tuner for use in mobile television devices comprises at least
one RF front end component comprising a LNA adapted to amplify
mobile television signals; a PLL circuit to generate signals; and a
pair of mixers to receive the signals from the LNA and the PLL
circuit and downconvert the signals; an analog baseband component
connected to the RF front end component, wherein the analog
baseband component comprises I and Q channel signal paths each
comprising a tunable high order impedance filter; at least one
signal amplification stage; and a signal filter stage connected to
the signal amplification stage, wherein the analog baseband
component further comprises a plurality of switches operatively
connected to the I and Q channel signal paths, and wherein the
plurality of switches are selectively opened and closed in multiple
configurations in order to allow the tuner to receive mobile TV
signals for all mobile TV standards.
Inventors: |
Abdelgany; Mohy (Irvine,
CA), Carr; Frank (New Coast, CA), Elwan; Hassan
(Mission Viejo, CA), Fahim; Amr (Newport Beach, CA),
Youssoufian; Edward (Irvine, CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
Abdelgany; Mohy
Carr; Frank
Elwan; Hassan
Fahim; Amr
Youssoufian; Edward |
Irvine
New Coast
Mission Viejo
Newport Beach
Irvine |
CA
CA
CA
CA
CA |
US
US
US
US
US |
|
|
Assignee: |
Newport Media, Inc. (Lake
Forest, CA)
|
Family
ID: |
39871804 |
Appl.
No.: |
13/645,471 |
Filed: |
October 4, 2012 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
11737222 |
Apr 19, 2007 |
7973861 |
Jul 5, 2011 |
|
|
Current U.S.
Class: |
348/731 |
Current CPC
Class: |
H04N
5/50 (20130101); H04N 21/41407 (20130101); H03J
1/005 (20130101); H03D 3/007 (20130101) |
Current International
Class: |
H04N
5/50 (20060101) |
Field of
Search: |
;348/731,725,726,723,552,553 ;375/347,316
;455/91,303,307,333,213,232.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Ironi, A., "Mobile TV standards: One size doesn't fit
all,"http://www.totaltele.com/View.aspx?ID=91546&t=4, Apr. 17,
2007. cited by applicant.
|
Primary Examiner: Natnael; Paulos M
Attorney, Agent or Firm: Rahman LLC
Claims
What is claimed is:
1. A tuner for use in .[.mobile television.]. .Iadd.communication
.Iaddend.devices, said tuner comprising: at least one radio
frequency (RF) front end component comprising: a low noise
amplifier (LNA) adapted to amplify .[.mobile television.].
.Iadd.communication .Iaddend.signals; a phase-locked loop (PLL)
circuit adapted to generate signals; and a pair of mixers adapted
to receive the signals from said LNA and said PLL circuit and
downconvert the received signals; an analog baseband component
operatively connected to said RF front end component, wherein said
analog baseband component comprises an I channel signal path and a
Q channel signal path, and wherein each of the I and Q channel
signal paths comprise: a tunable high order impedance filter; at
least one signal amplification stage; and a signal filter stage
operatively connected to said at least one signal amplification
stage, wherein said analog baseband component further comprises a
plurality of switches operatively connected to said I and Q channel
signal paths, and wherein said plurality of switches are
selectively opened and closed in multiple configurations in order
to allow said tuner to receive .[.mobile TV.]. .Iadd.communication
.Iaddend.signals .[.for all mobile TV standards.]..
2. The tuner of claim 1, further comprising a polyphase filter
operatively connected to said I and Q channel signal paths.
3. The tuner of claim 2, wherein said plurality of switches
comprises a switch configured between one of said at least one
signal amplification stage of said I channel signal path and said
polyphase filter.
4. The tuner of claim 3, wherein said switch is configured prior to
said polyphase filter along said I channel signal path.
5. The tuner of claim 3, wherein said switch is configured after to
said polyphase filter along said I channel signal path.
6. The tuner of claim 2, wherein said plurality of switches
comprises a switch configured between one of said at least one
signal amplifications stage of said Q channel signal path and said
polyphase filter.
7. The tuner of claim 2, wherein said plurality of switches
comprises a switch configured between two signal amplifications
stages along each of said I and Q channel signal paths.
8. The tuner of claim 2, wherein said plurality of switches
comprises a switch configured between one of said at least one
signal amplification stage and said signal filter stage along each
of said I and Q channel signal paths.
9. The tuner of claim 1, wherein said tunable high order impedance
filter comprises a complex tunable high order impedance filter.
10. The tuner of claim 2, wherein said plurality of switches
comprise: a first switch configured between one of said at least
one signal amplification stage of said I channel signal path and
said polyphase filter, wherein said first switch is configured
prior to said polyphase filter; a second switch configured between
one of said at least one signal amplification stage of said Q
channel signal path and said polyphase filter, wherein said second
switch is configured prior to said polyphase filter; a third switch
configured after said polyphase filter and prior to any of a second
one of said at least one signal amplification stage of said I
channel signal path and said signal filter stage of said I channel
signal path; a fourth switch configured between said one of said at
least one signal amplification stage along said I channel signal
path and any of a second one of said at least one signal
amplification stage of said I channel signal path and said signal
filter stage of said I channel signal path; and a fifth switch
configured between said one of said at least one signal
amplification stage along said Q channel signal path and any of a
second one of said at least one signal amplification stage of said
I channel signal path and said signal filter stage of said Q
channel signal path.
11. The tuner of claim 10, wherein when the first, second, third,
fourth, and fifth switches are opened, said tuner is adapted to
.[.(i) receive Frequency Modulation (FM) radio signals, and (ii)
receive mobile television signals for Digital Video
Broadcast--Terrestrial (DVB-T), Digital Video Broadcast--Handheld
(DVB-H), Terrestrial--Digital Multimedia Broadcast (T-DMB),
Integrated Services Digital Broadcast--Terrestrial (ISDB-T); Media
Forward Link Only (MediaFLO.TM.), and Digital Audio Broadcast (DAB)
wireless television standards.]. .Iadd.receive communication
signals.Iaddend..
12. The tuner of claim 10, wherein when the first, second, and
third switches are opened and the fourth and fifth switches are
closed, said tuner is adapted to .[.(i) receive Frequency
Modulation (FM) radio signals, and (ii) receive mobile television
signals for Digital Video Broadcast--Terrestrial (DVB-T), Digital
Video Broadcast--Handheld (DVB-H), and Media Forward Link Only
(MediaFLO.TM.) wireless television standards.]. .Iadd.receive
communication signals.Iaddend..
13. The tuner of claim 10, wherein when the first, second, and
third switches are closed and the fourth and fifth switches are
opened, said tuner is adapted to receive .[.mobile television
signals for Terrestrial--Digital Multimedia Broadcast (T-DMB),
Integrated Services Digital Broadcast--Terrestrial (ISDB-T), and
Digital Audio Broadcast (DAB) wireless television standards.].
.Iadd.communication signals.Iaddend..
14. The tuner of claim 11, wherein the opened switches enable said
timer to operate in a direct conversion mode.
15. The tuner of claim 12, wherein the opened switches enable said
tuner to operate in a direct conversion mode.
16. The tuner of claim 13, wherein the opened switches enable said
tuner to operate in a low-IF heterodyne mode.
17. The tuner of claim 1, wherein said plurality of switches that
are selectively opened cause circuit elements operatively connected
to said opened switches and after the opened switches along said I
and Q channel signal paths to refrain from consuming power.
18. The tuner of claim 1, further comprising at least one AC
coupling capacitor configured along said I and Q channel signal
paths.
19. A wireless receiver for use in .[.mobile television.].
.Iadd.communication .Iaddend.devices, said wireless receiver
comprising: at least one radio frequency (RF) front end component
comprising: a low noise amplifier (LNA) adapted to amplify
.[.mobile television.]. .Iadd.communication .Iaddend.signals; a
phase-locked loop (PLL) circuit adapted to generate signals; and a
pair of mixers adapted to receive the signals from said LNA and
said PLL circuit and downconvert the received signals; an analog
baseband component operatively connected to said RF front end
component, wherein said analog baseband component comprises: an I
channel signal path; a Q channel signal path; a polyphase filter
operatively connected to the I and Q channel signal paths; and at
least five switches operatively connected to said I and Q channel
signal paths, wherein said at least five switches are selectively
opened and closed in multiple configurations in order to allow said
wireless receiver to receive .[.mobile TV.]. .Iadd.communication
.Iaddend.signals .[.for all mobile TV standards.]., and wherein
said at least five switches that are selectively opened cause
circuit elements operatively connected to said opened switches and
after the opened switches along said I and Q channel signal paths
to refrain from consuming power.
20. A method of receiving a .[.television.]. signal in a .[.mobile
television.]. .Iadd.communication .Iaddend.device, said method
comprising: amplifying a .[.mobile television.].
.Iadd.communication .Iaddend.signal using a low noise amplifier
(LNA) in at least one radio frequency (RF) front end component of
said device; generating signals using a phase-locked loop (PLL)
circuit in said at least one RF front end component of said device;
downconverting the amplified .[.mobile television.].
.Iadd.communication .Iaddend.signal from said LNA and said signals
from said PLL in a pair of mixers in said at least one RF front end
component of said device; transmitting the converted signal along
at least one of an I and Q channel signal path in an analog
baseband component of said device, wherein each of the I and Q
channel signal paths comprise: a tunable high order impedance
filter; at least one signal amplification stage; and a signal
filter stage operatively connected to said at least one signal
amplification stage, filtering said converted signal along the I
and Q channel signal paths; amplifying said converted signal along
said I and Q channel signal path; and selectively diverting said
converted signal along said I and Q channel signal path by
selectively opening and closing a plurality of switches in said
analog baseband component to selectively allow said device to
receive radio signals and mobile television signals for all mobile
television standards.
.Iadd.21. The tuner of claim 1, wherein said communication signals
comprise mobile television communication signals..Iaddend.
.Iadd.22. The receiver of claim 19, wherein said communication
signals comprise mobile television communication
signals..Iaddend.
.Iadd.23. The method of claim 20, wherein said communication
signals comprise mobile television communication signals..Iaddend.
Description
.Iadd.CROSS REFERENCE TO RELATED APPLICATION.Iaddend.
.Iadd.This application is a reissue of U.S. Pat. No. 7,973,861,
issued on Jul. 5, 2011, the contents of which in its entirety, is
herein incorporated by reference..Iaddend.
BACKGROUND
1. Technical Field
The embodiments herein generally relate to wireless communications,
and, more particularly, to mobile television (TV) technologies.
2. Description of the Related Art
The field of wireless communications, and specifically mobile TV,
is plagued with numerous standards that are supported in different
parts of the world. This problem led to the requirement of having
multi-mode mobile TV devices capable of supporting multiple
standards. This is problematic due to the wide variation in
specifications of each standard, especially data bandwidth. For
high bandwidth standards, a direct conversion front-end receiver
architecture is desired for several reasons. First, after mixing
down the radio frequency (RF) signal, the baseband operates at the
minimum operating frequency (minimizing bandwidth). Second, image
rejection is completely eliminated, since there is no intermediate
frequency (IF). For low data bandwidth standards, a low-IF
heterodyne architecture is desired. A low-IF heterodyne
architecture avoids low-frequency flicker noise produced by
baseband analog circuitry by shifting the data signal to a
frequency slightly away from DC.
One method to realize a multi-standard tuner is to use multiple
receiver paths for each standard. While this method is relatively
straightforward, it tends to suffer from a number of drawbacks
including requiring a large chip/die-area, which translates to
lower yield and higher cost; and a lamer die area also generally
requires larger packages and hence a higher packaging cost as well
as a larger printed circuit board (PCB) area. Accordingly, for
multi-standard communication systems, there is a strong need for
one receiver architecture that can accommodate both narrow
bandwidth and high bandwidth standards.
SUMMARY
In view of the foregoing, an embodiment provides a tuner for use in
mobile television devices, wherein the tuner comprises at least one
RF front end component comprising a low noise amplifier (LNA)
adapted to amplify mobile television signals; a phase-locked loop
(PLL) circuit adapted to generate signals; and a pair of mixers
adapted to receive the signals from the LNA and the PLL circuit and
downconvert the received signals; an analog baseband component
operatively connected to the RF front end component, wherein the
analog baseband component comprises an I channel signal path and a
Q channel signal path, and wherein each of the I and Q channel
signal paths comprise a tunable high order impedance filter; at
least one signal amplification stage; and a signal filter stage
operatively connected to the at least one signal amplification
stage, wherein the analog baseband component further comprises a
plurality of switches operatively connected to the I and Q channel
signal paths, and wherein the plurality of switches are selectively
opened and closed in multiple configurations in order to allow the
tuner to receive mobile TV signals for all mobile TV standards. The
plurality of switches that are selectively opened cause circuit
elements operatively connected to the opened switches and after the
opened switches along the I and Q channel signal paths to refrain
from consuming power.
The tuner may further comprise a polyphase filter operatively
connected to the I and Q channel signal paths. The plurality of
switches may comprise a switch configured between one of the at
least one signal amplification stage of the I channel signal path
and the polyphase filter. A switch may be configured prior to the
polyphase filter along the I channel signal path. Additionally, a
switch may be configured after to the polyphase filter along the I
channel signal path. The plurality of switches may comprise a
switch configured between one of the at least one signal
amplifications stage of the Q channel signal path and the polyphase
filter.
Also, the plurality of switches may comprise a switch configured
between two signal amplifications stages along each of the I and Q
channel signal paths. Moreover, the plurality of switches may
comprise a switch configured between one of the at least one signal
amplification stage and the signal filter stage along each of the I
and Q channel signal paths. Additionally, the tunable high order
impedance filter may comprise a complex tunable high order
impedance filter.
Also, the plurality of switches may comprise a first switch
configured between one of the at least one signal amplification
stage of the I channel signal path and the polyphase filter,
wherein the first switch is configured prior to the polyphase
filter; a second switch configured between one of the at least one
signal amplification stage of the Q channel signal path and the
polyphase filter, wherein the second switch is configured prior to
the polyphase filter; a third switch configured after the polyphase
filter and prior to any of a second one of the at least one signal
amplification stage of the I channel signal path and the signal
filter stage of the I channel signal path; a fourth switch
configured between the one of the at least one signal amplification
stage along the I channel signal path and any of a second one of
the at least one signal amplification stage of the I channel signal
path and the signal filter stage of the I channel signal path; and
a fifth switch configured between the one of the at least one
signal amplification stage along the Q channel signal path and any
of a second one of the at least one signal amplification stage of
the I channel signal path and the signal filter stage of the Q
channel signal path.
Preferably, when the first, second, third, fourth, and fifth
switches are opened, the tuner is adapted to (i) receive Frequency
Modulation (FM) radio signals, and (ii) receive mobile television
signals for Digital Video Broadcast--Terrestrial (DVB-T), Digital
Video Broadcast--Handheld (DVB-H), Terrestrial--Digital Multimedia
Broadcast (T-DMB), Integrated Services Digital
Broadcast--Terrestrial (ISDB-T); Media Forward Link Only
(MediaFLO.TM.), and Digital Audio Broadcast (DAB) wireless
television standards, wherein the opened switches enable the tuner
to operate in a direct conversion mode. Moreover, when the first,
second, and third switches are opened and the fourth and fifth
switches are closed, the tuner is preferably adapted to (i) receive
FM radio signals, and (ii) receive mobile television signals for
DVB-T, DVB-H, and Media Forward Link Only MediaFLO.TM. wireless
television standards, wherein the opened switches enable the tuner
to operate in a direct conversion mode.
Furthermore, wherein when the first, second, and third switches are
closed and the fourth and fifth switches are opened, the tuner is
preferably adapted to receive mobile television signals for
Terrestrial--Digital Multimedia Broadcast (T-DMB), Integrated
Services Digital Broadcast--Terrestrial (ISDB-T), and Digital Audio
Broadcast (DAB) wireless television standards, wherein the opened
switches enable the tuner to operate in a low-IF heterodyne mode.
The tuner may further comprise at least one AC coupling capacitor
configured along the I and Q channel signal paths.
Another embodiment provides a wireless receiver for use in mobile
television devices, wherein the wireless receiver comprises at
least one RF front end component comprising a LNA adapted to
amplify mobile television signals; a PLL circuit adapted to
generate signals; and a pair of mixers adapted to receive the
signals from the LNA and the PLL circuit and downconvert the
received signals. The receiver further comprises an analog baseband
component operatively connected to the RF front end component,
wherein the analog baseband component comprises an I channel signal
path; a Q channel signal path; a polyphase filter operatively
connected to the I and Q channel signal paths; and at least five
switches operatively connected to the I and Q channel signal paths,
wherein the at least five switches are selectively opened and
closed in multiple configurations in order to allow the wireless
receiver to receive mobile TV signals for all mobile TV standards,
and wherein the at least five switches that are selectively opened
cause circuit elements operatively connected to the opened switches
and after the opened switches along the I and Q channel signal
paths to refrain from consuming power.
Another embodiment provides a method of receiving a television
signal in a mobile television device, wherein the method comprises
downconverting an amplified mobile television signal in a wireless
receiver; transmitting the converted signal along at least one of
an I and Q channel signal path in the wireless receiver; filtering
the converted signal along the I and Q channel signal paths;
amplifying the converted signal along the I and Q channel signal
path; and selectively diverting the converted signal along the I
and Q channel signal path to selectively allow the receiver to
receive FM radio signals and receive mobile television signals for
each of DVB-T, DVB-H, T-DMB, ISDB-T; MediaFLO.TM., and DAB wireless
television standards.
These and other aspects of the embodiments herein will be better
appreciated and understood when considered in conjunction with the
following description and the accompanying drawings. It should be
understood, however, that the following descriptions, while
indicating preferred embodiments anti numerous specific details
thereof, are given by way of illustration and not of limitation.
Many changes and modifications may be made within the scope of the
embodiments herein without departing from the spirit thereof, and
the embodiments herein include all such modifications.
BRIEF DESCRIPTION OF THE DRAWINGS
The embodiments herein will be better understood from the following
detailed description with reference to the drawings, in which:
FIGS. 1 through 5 illustrate schematic circuit diagrams of a
wireless tuner/receiver used in mobile TV devices utilizing various
mobile TV standards according to the embodiments herein; and
FIG. 6 is a flow diagram illustrating a preferred method according
to an embodiment herein.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The embodiments herein and the various features and advantageous
details thereof are explained more fully with reference to the
non-limiting embodiments that are illustrated in the accompanying
drawings and detailed in the following description. Descriptions of
well-known components and processing techniques are omitted so as
to not unnecessarily obscure the embodiments herein. The examples
used herein are intended merely to facilitate an understanding of
ways in which the embodiments herein may be practiced and to
further enable those of skill in the art to practice the
embodiments herein. Accordingly, the examples should not be
construed as limiting the scope of the embodiments herein.
As mentioned, for multi-standard communication systems, there is a
strong need for one receiver architecture that can accommodate both
narrow bandwidth and high bandwidth standards. The embodiments
herein achieve this by providing a new universal mobile-TV tuner
integrated circuit. The architecture provided by the embodiments
herein enables the tuner to receive mobile TV and audio signals in
various bands and various standards. The architecture can be
programmed into various configurations to suit various standards
and allow optimal dynamic range and power trade-offs. Referring now
to the drawings, and more particularly to FIGS. 1 through 6, where
similar reference characters denote corresponding features
consistently throughout the figures, there are shown preferred
embodiments.
The embodiments herein provide a method and apparatus for a
universal receiver or tuner that is suitable for multi-standard
wireless systems, especially mobile TV and radio standards such as
Digital Video Broadcast--Terrestrial (DVB-T), Digital Video
Broadcast--Handheld (DVB-H), Terrestrial--Digital Multimedia
Broadcast (T-DMB), Integrated Services Digital
Broadcast--Terrestrial (ISDB-T), Media Forward Link Only
(MediaFLO.TM.), Digital Audio Broadcast (DAB), Advanced Television
Systems Committee (ATSC), and Frequency Modulation (FM). The terms
"tuner" and "receiver" are interchangeably used herein.
FIGS. 1 through 4 illustrate a tuner 100, which may be configured
differently depending on which mobile TV or radio standard is
desirable, whereby the changes in configurations are controlled by
the opening/closing of a plurality of switches (S.sub.1 through
S.sub.5) in the tuner 100. The tuner 100 comprises a RF front end
101 comprising a low noise amplifier (LNA) 102 with automatic gain
control (AGC) and a pair of mixers 103a, 103b adapted to receive
signals from a voltage controlled oscillator phase-locked loop
(VCO/PLL) circuit 105. The local oscillator (LO) port 104 of the
mixer 103b controls whether the receiver 100 is in direct
conversion mode or low-IF heterodyne mode. In direct conversion
mode, the LO frequency is set to be the same as the RF frequency.
In low-IF heterodyne mode, the LO frequency is offset from the RF
center frequency by a value equal to the desired IF frequency; in
other words, IF=+/-(RF-LO). A direct conversion mode is more
suitable for wider band signals and when the signal is surrounded
by larger blockers (hence the image rejection requirement is very
high for low-IF architectures). A low-IF mode is more suitable for
lower bandwidth signals that has a smaller blocker profile (even in
the adjacent channel) and hence the image rejection requirement is
not stringent. One benefit of the low-IF mode is it avoids the
problem of DC-Offset, can offer a better second-order intercept
point (IIP2) performance and in some cases can save on power
consumption (such as the ISDB-T mode (FIG. 4)).
After downconversion through mixers 103a, 103b, the signal enters
the universal analog baseband 106 portion of the receiver 100
whereby the signal is filtered and amplified by filters 107a, 107b
and amplifiers 108a, 108b, respectively. Filters 107a, 107b are
programmable (for generality) so in some modes with larger blockers
the filter 107a, 107b switches are short and hence the filters
107a, 107b attenuate the blockers. For other modes if the blocker
profile is not as aggressive, the filters 107a, 107b are switched
off and powered down to save power. Moreover, the filters 107a,
107b may be embodied as tunable high order impedance filters 107a,
107b (FIGS. 1-3) or complex high order impedance filters 107a',
107b' (FIG, 4). The complex high order filter 107a', 107b' (FIG. 4)
provides enhanced image rejection compared with filters 107a, 107b
(FIGS. 1 through 3).
For the low-IF mode (FIG. 3), a polyphase filter 109 combines I and
Q channels to form one low-IF channel. In the direct conversion
mode (FIGS. 1, 2, and 4), the polyphase filter 109 is bypassed and
the signal continues through the receiver 100 along the I and Q
signal paths, respectively, where they are further processed by
subsequent filtering 110a, 110b and amplification 111a, 111b, 112a,
112b stages. The polyphase filter 109 can be configured to provide
high or low side injection, which may aid in reducing the infrared
(IR) requirement when blockers are present. Preferably, filters
110a, 110b are tunable filters. The tunable filter frequency range
is large, and is from 200 kHZ (FM) to 4 MHz (DVB-H). This large
frequency rang is covered by combining band switching (coarse) with
in-band (fine) tuning and comprises of smaller discrete frequency
steps.
The embodiments herein support both low-IF and direct conversion
receiver modes, which are suitable for narrow band and wide band
standards, respectively. The selection can be performed through
hardware and/or software configuration. Additionally, the first
stage filter 107a, 107b attenuates out-of-band blockers and reduces
the linearity requirements of subsequent stages 108a, 108b, 109,
110a, 110b, 111a, 111b, 112a, 112b). This filtering can be
performed by a low-noise filter, for example. Alternatively, a low
noise amplifier (not shown) can supersede the filter stage 107a,
107b to reduce the noise requirement of the filter 107. Moreover,
amplifiers 108a, 108b, 111a, 111b, 112a, 112b can be placed in any
order, individually removed, or configured as variable gain
amplifiers. Furthermore, the receiver 100 provides a flexible
trade-off between low-frequency noise and power consumption which
allows the user to select receiver optimization for power
consumption or performance. In this regard, in FIGS. 1 through 4,
circuit elements that are not used (via open switches) are powered
down thereby providing overall power consumption savings for the
receiver 100. In the context of mobile TV, the receiver 100 can be
used in direct conversion mode for DVB-T/H, Media-FLO, and DMB
systems and used in low-IF mode for ISDB-T and FM.
FIG. 1 illustrates the tuner 100 being implemented in a direct
conversion mode using the following wireless standards: DVB-H,
DVB-T, ISDB-T, MedaFLO.TM., T-DMB, DAB, and FM. in this embodiment,
switches S.sub.1, S.sub.2, S.sub.3, S.sub.4, and S.sub.5 are all
open switches, which effectively results in the circuit blocks
included after the amplifiers 108a, 108b in the receiver 100 to be
powered down with the Q and I signals being directly outputted from
the amplifiers 108a, 108b, respectively. Moreover, in this
embodiment the filters 107a, 107b are embodied as tunable high
order impedance filters.
FIG. 2 illustrates the tuner 100 being implemented in a direct
conversion mode using the following wireless standards: DVB-H,
DVB-T, MediaFLO.TM., and FM. In this embodiment, switches S.sub.1,
S.sub.2, and S.sub.3 are all open switches while switches S.sub.4
and S.sub.5 are closed switches, which effectively results in the
polyphase filter 109 being powered down with the Q and I signals
being directly passed through the amplifier/filter/amplifier stage
111a, 110a, 112a and amplifier/filter/amplifier stage 111b, 110b,
112b, respectively. Moreover, in this embodiment the filters 107a,
107b are embodied as tunable high order impedance filters.
FIG. 3 illustrates the tuner 100 being implemented in a low-IF mode
using the following wireless standards: ISDB-T, T-DMB, and DAB. In
this embodiment, switches S.sub.1, S.sub.2, and S.sub.3 are all
closed switches while switches S.sub.4 and S.sub.5 are open
switches, which effectively results in the signal coming from the
amplifiers 108a, 108b to proceed through the polyphase filter 109
with the amplifier/filter/amplifier stage 111a, 110a, 112a being
powered down and with the low IF output signal being directly
passed through the amplifier/filter/amplifier stage 111b, 110b,
112b only. Moreover, in this embodiment the filters 107a, 107b are
embodied as tunable high order impedance filters.
FIG. 4 illustrates the tuner 100 being implemented in a direct
conversion mode using the following wireless standards: DVBV-H,
DVB-T, ISDB-T, MediaFLO.TM., T-DMB, DAB, and FM. In this
embodiment, switches S.sub.1, S.sub.2, S.sub.3, S.sub.4, and
S.sub.5 are all open switches, which effectively results in the
polyphase filter 109 being powered down with the Q and I signals
being directly passed through the amplifier/filter/amplifier stage
111a, 110a, 112a and amplifier/filter/amplifier stage 111b, 110b,
112b, respectively. Moreover, in this embodiment the filters (107a,
107b of FIGS. 1-3) are embodied as a complex tunable high order
impedance filter 107'.
FIG. 5 illustrates the tuner 100 being implemented in either a
low-IF mode or a direct conversion mode using the following
wireless standards: DVB-H, DVB-T, ISDB-T, MediaFLO.TM., DMB-T, DAB,
and FM. In this embodiment, multiple RF front ends 101, 101' are
utilized, however signals are applied to only one baseband 106 and
in operation only one LNA/mixer (either LNA/mixer 102/103a, 103b or
LNA/mixer 102'/103a', 103b') is enabled at a time (as denoted by
the dotted lines in FIG. 5 depicting that the signals are
selectively sent from the VCO/PLL 105 to mixers 103a, 103b and
mixers 103a', 103b'. The tuner architecture 100 shown in FIG. 5
allows the use of separate LNAs 102, 102' and mixers 103a, 103a',
103b, and 103b' for different RF bands. This makes the design of
the front end 101, 101' more optimized for the frequency band it is
handling. Furthermore, the frequency range needed by the VCO/PLL
105 is also reduced. For example, instead of covering the entire
range of 200 MHz to 2 GHZ, a divide-by-two and a divide-by-four
circuit can be used. Therefore, a 2 GHz signal can be divided by
four to produce a 500 MHz signal. Therefore, the VCO/PLL 105 is
never required to operate at 500 MHz (i.e., the VCO/PLL 105 can
stay at 2 GHZ+/-delta for tuning).
FIG. 6, with respect to FIGS. 1 through 5, is a flow diagram
illustrating a method of receiving a television signal in a mobile
television device according to an embodiment herein, wherein the
method comprises downconverting (151) an amplified mobile
television signal in a wireless receiver 100; transmitting (153)
the converted signal along at least one of an I and Q channel
signal path in the wireless receiver 100; filtering (155) the
converted signal along the I and Q channel signal paths; amplifying
(157) the converted signal along the I and Q channel signal path;
and selectively diverting (159) the converted signal along the I
and Q channel signal path to selectively allow the receiver 100 to
receive FM radio signals and receive mobile television signals for
each of DVB-T, DVB-H, T-DMB, ISDB-T; MediaFLO.TM., and DAB wireless
television standards.
The embodiments herein can take the form of an entirely hardware
embodiment, an entirely software embodiment or an embodiment
including both hardware and software elements. The embodiments
implemented in software include, but is not limited to firmware,
resident software, microcode, etc. Furthermore, the embodiments
herein can take the form of a computer program product accessible
from a computer-usable or computer-readable medium providing
program code for use by or in connection with a computer or any
instruction execution system. For the purposes of this description,
a computer-usable or computer readable medium can be any apparatus
that can comprise, store, communicate, propagate, or transport the
program for use by or in connection with the instruction execution
system, apparatus, or device.
The medium can be an electronic, magnetic, optical,
electromagnetic, infrared, or semiconductor system (or apparatus or
device) or a propagation medium. Examples of a computer-readable
medium include a semiconductor or solid state memory, magnetic
tape, a removable computer diskette, a random access memory (RAM),
a read-only memory (ROM), a rigid magnetic disk and an optical
disk. Current examples of optical disks include compact disk-read
only memory (CD-ROM), compact disk-read/write (CD-R/W) and DVD.
A data processing system suitable for storing and/or executing
program code will include at least one processor coupled directly
or indirectly to memory elements through a system bus. The memory
elements can include local memory employed during actual execution
of the program code, bulk storage, and cache memories which provide
temporary storage of at least some program code in order to reduce
the number of times code must be retrieved from bulk storage during
execution.
Input/output (I/O) devices (including but not limited to keyboards,
displays, pointing devices, etc.) can be coupled to the system
either directly or through intervening I/O controllers. Network
adapters may also be coupled to the system to enable the data
processing system to become coupled to other data processing
systems or remote printers or storage devices through intervening
private or public networks. Modems, cable modem and Ethernet cards
are just a few of the currently available types of network
adapters.
The embodiments herein provide an integrated wireless tuner that
can be embedded on an integrated circuit chip and that can be
programmed to receive any mobile TV signal in various bands and in
various mobile TV standards. The tuner utilizes programmable blocks
that can be re-used and re-programmed in different configurations
to optimize the performance for different standards. Block-re-use
offers the advantage of reduced die area and cost. The tuner
architecture can be configured as a low-IF receiver or a Direct
Conversion Receiver (DCR) depending on the received signal
characteristics. In the DCR embodiment, the receiver 100 includes
AC coupling capacitors (not shown) between various stages that can
be bypassed accordingly. Those skilled in the art would readily
understand how such capacitors could be configured in the receiver
100. The DCR mode is suitable for wider bandwidth and there are no
image rejection requirements. Moreover, the receiver 100 is
implemented for the ATSC mobile TV standard in the DCR mode. The
low-IF mode is suitable for low bandwidth signals, and this mode
does not suffer from flicker noise and DC offset problems.
Moreover, the tuner 100 provides programmable filtering and gain
control to suit the need of each mobile-TV standard.
The foregoing description of the specific embodiments will so fully
reveal the general nature of the embodiments herein that others
can, by applying current knowledge, readily modify and/or adapt for
various applications such specific embodiments without departing
from the generic concept, and, therefore, such adaptations and
modifications should and are intended to be comprehended within the
meaning and range of equivalents of the disclosed embodiments. It
is to be understood that the phraseology or terminology employed
herein is for the purpose of description and not of limitation.
Therefore, while the embodiments herein have been described in
terms of preferred embodiments, those skilled in the art will
recognize that the embodiments herein can be practiced with
modification within the spirit and scope of the appended
claims.
* * * * *
References