U.S. patent application number 16/525864 was filed with the patent office on 2021-02-04 for method and apparatus to maximize simultaneous modem operations in a converged communication device.
The applicant listed for this patent is MOTOROLA SOLUTIONS, INC.. Invention is credited to JAVIER ALFARO, MARK ANTILLA, MARK A BOERGER, DENNIS A BYK.
Application Number | 20210037536 16/525864 |
Document ID | / |
Family ID | 1000004277236 |
Filed Date | 2021-02-04 |
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United States Patent
Application |
20210037536 |
Kind Code |
A1 |
ALFARO; JAVIER ; et
al. |
February 4, 2021 |
METHOD AND APPARATUS TO MAXIMIZE SIMULTANEOUS MODEM OPERATIONS IN A
CONVERGED COMMUNICATION DEVICE
Abstract
A portable communication device provides improved converged
operations through the use of a programmable logic array operating
as a coexistence module (CEM) interoperating with different
processors, different modems, and an attenuation switch.
Interference during converged operation is detected, analyzed, and
applicable mitigation is applied, thereby enabling converged
communications to be established in a mitigated mode until the
interference has been removed.
Inventors: |
ALFARO; JAVIER; (MIAMI,
FL) ; BYK; DENNIS A; (FT. LAUDERDALE, FL) ;
BOERGER; MARK A; (PLANTATION, FL) ; ANTILLA;
MARK; (DAVIE, FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MOTOROLA SOLUTIONS, INC. |
Chicago |
IL |
US |
|
|
Family ID: |
1000004277236 |
Appl. No.: |
16/525864 |
Filed: |
July 30, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 84/042 20130101;
H04W 72/082 20130101; H04W 88/06 20130101; H04W 74/0816
20130101 |
International
Class: |
H04W 72/08 20060101
H04W072/08; H04W 88/06 20060101 H04W088/06; H04W 84/04 20060101
H04W084/04; H04W 74/08 20060101 H04W074/08 |
Claims
1. A portable communication device, comprising: a programmable
logic array operating as a coexistence module (CEM); an
applications processor (AP) operatively coupled to the CEM; a
baseband processor (BP) operatively coupled to the CEM; a first
modem operatively coupled to the BP, the first modem operating
using a first frequency band; a second modem operatively coupled to
the AP, the second modem operating using a second frequency band;
the AP, the BP, and the first and second modems operating in a
converged mode in which both the first and second modems operate
simultaneously; an attenuation switch operatively coupled to the
CEM and the second modem; the BP generating signals to the CEM and
to the AP while the first modem is transmitting and receiving on
the first frequency band; the second modem generating signals to
the CEM and to the AP when the second modem is transmitting and
receiving on the second frequency band; and the AP and the CEM
detecting signals indicating interference between the first and
second frequency bands, the CEM engaging the attenuation switch to
temporarily disconnect an antenna path of the second modem while
the AP determines an applicable interference mitigation to counter
the interference, the AP applying the interference mitigation to
enable the second modem to operate in a restricted mode; and the AP
generating a disengage signal to the CEM, and the CEM disengaging
the attenuation switch in response thereto, thereby re-establishing
converged operation during which the first modem and second modems
operate simultaneously, the second modem operating in the
restricted mode.
2. The portable communication device of claim 1, wherein the CEM
detects changes to the detected interference and instructs the AP
to disengage the interference mitigation, thereby returning the
first and second modems to regular converged operation.
3. The portable communication device of claim 1, wherein
interference between the first and second frequency bands comprises
one or more of: second modem transmit frequency bands conflicting
with first modem receive bands; external RF energy interfering with
the second modem; internal first modem transmissions interfering
with the second modem; and second modem transmit frequency bands
interfering with internally generated first modem
transmissions.
4. The portable communication device of claim 3, wherein the
interference mitigation comprises at least one of: power reduction
to the second modem; data throttling to the second modem; band
steering of the second modem.
5. The portable communication device of claim 1, wherein the first
frequency communication band is configurable frequency band.
6. The portable communication device of claim 1, further
comprising: a first antenna associated with the first modem; and a
second antenna associated with the second modem; an RF detector
operatively coupled between the second antenna, the second modem,
and the CEM, the RF detector for detecting an RF energy associated
with the first communication frequency band being present at the
second antenna and exceeding a predetermined RF energy threshold;
and the CEM engaging the attenuation switch while detecting that
the RF energy exceeds the predetermined RF energy threshold.
7. The portable communication device of claim 7, wherein the RF
energy is caused by at least one of: internal transmissions
interfering with the second modem; external transmissions
interfering with the second modem.
8. The portable communication device of claim 1, wherein the first
and second modems support communication protocols operating over
frequency bands which are susceptible to interference with each
other.
9. The portable communication device of claim 1, wherein the first
modem is a land mobile radio (LMR) modem and the second modem is a
long term evolution (LTE) modem.
10. The portable communication device of claim 1, wherein the AP
waits for a configurable holdoff timer to expire and validates that
the interference is still present before applying the interference
mitigation.
11. The portable communication device of claim 2, wherein the AP
waits for a configurable holdoff timer to expire and validates that
the interference is still not present before removing the
interference mitigation.
12. A method for managing communications in a converged portable
communication device, the method comprising: simultaneously
operating first and second modems over first and second frequency
bands in a regular converged mode of operation of the portable
communication device; detecting RF interference during the
converged mode of operation; engaging an attenuation switch to the
second modem to temporarily negate RF communications associated
with the second modem; determining a cause of interference as being
one from a plurality of predetermined interference scenarios;
determining whether a mitigation action is applicable based on the
determined cause of interference; applying the mitigation action to
establish a mitigated converged mode of operation; disengaging the
attenuation switch upon establishing the mitigated converged mode
of operation; and communicating using the mitigated converged mode
of operation.
13. The method of claim 12, wherein applying the mitigation action
comprises at least one of: applying reduced power to the second
modem; applying data speed throttling to the second modem; applying
band steering of the second modem.
14. The method of claim 12, further comprising: detecting removal
of the RF interference; and disengaging the interference
mitigation, thereby returning the first and second modems to
regular converged operation.
15. The method of claim 12, wherein the attenuation switch is
controlled by: a logic array operating as a coexistence module, the
logic array being responsive to: a baseband processor associated
with the first modem, an applications processor associated with the
second modem, and an external power detect circuit.
16. The method of claim 12, wherein detecting RF interference
comprises detecting at least one of: transmit frequency bands of
the second modem conflicting with receive bands of the first modem;
external RF energy interfering with the second modem; internal
first modem transmissions interfering with the second modem; second
modem transmit frequency bands interfering with internally
generated first modem transmissions.
17. The method of claim 12, wherein applying the mitigation action
further comprises: waiting for a configurable holdoff timer to
expire; and validating that the interference is still present
before applying the interference mitigation.
18. The method of 14, wherein detecting removal of the interference
further comprises: waiting for a configurable holdoff timer to
expire; and validating that the interference is still not present
before disengaging the interference mitigation.
19. The method of claim 12, wherein the first modem is a land
mobile radio (LMR) modem operating over an LMR frequency band, and
the second modem in a long term evolution (LTE) modem operating
over an LTE frequency band.
20. The method of claim 19, wherein the LMR modem remains fully
operational during the mitigation.
21. A portable communication device, comprising: a first processor
and a first modem managing mission-critical communications; a
second processor and a second modem managing non-mission
mission-critical communications; a first antenna coupled to the
first modem; a second antenna coupled to the second modem; a
coexistence module (CEM) operatively coupled to the first and
second processors and the second modem, the CEM detecting one of:
interference conditions and non-interference conditions, while the
first and second modems operate simultaneously during converged
operations; and an attenuation switch coupled between the second
antenna and the second modem, the attenuation switch being under
control of the CEM, the attenuation switch being disengaged during
normal converged operation in response to non-interference
conditions being detected by the CEM, and the attenuation switch
being temporarily engaged in response to interference conditions
being detected by the CEM, the attenuation switch being temporarily
engaged until interference mitigation is applied or the
interference has been removed.
Description
FIELD OF THE INVENTION
[0001] This application pertains to portable communication devices
and more particularly to managing modem operations of a converged
portable communication device.
BACKGROUND OF THE INVENTION
[0002] Portable battery powered communication devices are often
utilized in public safety environments, such as law enforcement,
fire rescue, and the like. There is an increased desire to expand
the functionality of public safety communication devices to
incorporate additional features that run on different operating
platforms, other than the main mission critical public safety
platform. Such devices may be referred to as converged devices. It
is highly desirable that a converged device be able to operate two
modems simultaneously. However, operating two modems simultaneously
can result in plethora of complex self-interference scenarios not
encountered in conventional single modem devices. For example,
out-of-band emissions, blocking and/or intermediation occurring in
one sub-system of a converged device may severely interfere with
the performance of another sub-system of the converged device.
Compliance with regulatory emission limits may also lead to
inter-modulation artifacts from one modem interference with nearby
spectrum of another modem.
[0003] Existing strategies to interference mitigation, such as
those used on single modem devices, do not lend themselves well to
converged devices, as these strategies tend to negatively impact
performance and timing of one or more sub-systems.
[0004] Hence, there is a need for an improved interference
mitigation approach in a converged portable communication
device.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0005] The accompanying figures, where like reference numerals
refer to identical or functionally similar elements throughout the
separate views, together with the detailed description below, are
incorporated in and form part of the specification, and serve to
further illustrate embodiments of concepts that include the claimed
invention, and explain various principles and advantages of those
embodiments.
[0006] FIG. 1 is a block diagram of a portable communication device
formed and operating in accordance with some embodiments.
[0007] FIG. 2 is a flowchart of a method for managing simultaneous
modem operations in a converged portable communication device in
accordance with some embodiments.
[0008] Skilled artisans will appreciate that elements in the
figures are illustrated for simplicity and clarity and have not
necessarily been drawn to scale. For example, the dimensions of
some of the elements in the figures may be exaggerated relative to
other elements to help to improve understanding of embodiments of
the present invention.
[0009] The apparatus and method components have been represented
where appropriate by conventional symbols in the drawings, showing
only those specific details that are pertinent to understanding the
embodiments of the present invention so as not to obscure the
disclosure with details that will be readily apparent to those of
ordinary skill in the art having the benefit of the description
herein.
DETAILED DESCRIPTION OF THE INVENTION
[0010] Briefly, there is provided herein an apparatus and method
for dynamically managing simultaneous modem operation in a portable
communication device. The embodiments are directed to mitigating
interference resulting from the simultaneous operation of the two
or more modems. Improved converged communications is provided
through the use of a programmable logic array operating as a
coexistence module (CEM) interoperating with a plurality of
different processors, a plurality of different modems, and a
plurality of attenuation switches. Interference during converged
operation is detected, analyzed, and applicable mitigation is
applied to the interference, thereby enabling converged
communications to be established in a mitigated mode. The mitigated
mode of operation continues until the interference has been
removed. Mission critical communications is maintained without
relying on the use of infrastructure collaboration.
[0011] FIG. 1 is a block diagram of a portable communication device
100 formed and operating in accordance with some embodiments. The
portable communication device 100 is powered by a battery (not
shown). The portable communication device 100 comprises a
programmable logic array operating as a coexistence module (CEM)
102, an applications processor (AP) 104 operatively coupled to the
CEM 102, and a baseband processor (BP) 106 operatively coupled to
the CEM and the AP. The portable communication device 100 further
comprise a first modem 108, such as a land mobile radio (LMR)
modem, operatively coupled to the BP 106, the first modem operating
using a first frequency band of operation. The first modem is
responsible for mission critical operations, such as scan,
push-to-talk (PTT), and high power audio. The portable
communication device 100 further comprises a second modem 110, such
as a long term evolution (LTE) modem, operatively coupled to the AP
104, the second modem operating using a second frequency band of
operation. The AP 104 is responsible for non-mission critical
operations, such as software applications associated with
touchscreen interface, low power audio, and global positioning
system (GPS). Other radio elements such as radio frequency (RF)
transmitters, receivers, power amplifiers are not shown (to
maintain simplicity) but are understood to be embodied within the
device 100.
[0012] In accordance with some embodiments, the AP 104, the BP 106,
and the first and second modems 108, 110 are operable in a
converged mode in which both the first and second modems operate
simultaneously receiving and transmitting signals via respective
first and second antennas 130, 132, such as an LMR antenna and an
LTE antenna. Data 140 is transferred between the baseband processor
106 and the first modem 108 and then via the LMR TX/RX 114 onto the
first antenna 130. For example, narrowband data is transferred
between the BP and the LMR modem and then to the LMR antenna. Data
142 is also transferred between the applications processor 104 and
the second modem 110 and then via the LTE TX/RX 116 onto the second
antenna 132. For example broadband data is transferred between the
AP and the LTE modem and then to the LTE antenna.
[0013] In accordance with the embodiments, the portable
communication device 100 further comprises an attenuation switch
112 operatively coupled to the CEM 102 and to the second modem 110.
The attenuation switch 112 operates as a hardware clamp to second
modem communications. The attenuation switch 112 is disengaged
during normal, non-interfered converged operation. During
engagement of the attenuation switch 112, incoming RF signals to
the second (LTE) antenna 132 are disconnected, thereby preventing
external RF energy from damaging the second modem 110. Protection
is also provided from internal RF energy generated from the first
modem (LMR internal). Additionally, outgoing RF signals from the
second modern 110 via the LTE TX/RX signal 116 are also
disconnected, thereby preventing RF Energy from the second modem
110 from interfering with the first modem 108. The methods employed
by the attenuation switch 112 may be one of shunting the antenna
path to ground, or providing an open circuit between the antenna
path and the second modem. The attenuation switch 112 may also be
realized as a plurality of switches each acting on a plurality of
paths to the second modem 110 and a plurality of second antennas
132.
[0014] During converged operation, the BP 106 further generates
indicator signals 118, 120 to the CEM 102 and to the AP 104 while
the first modem 108 is transmitting and receiving on a first
frequency band. Simultaneously, the second modem 110 is generating
indicator signals 122 to the CEM 102 and the AP 104 while
transmitting and receiving on the second frequency band. For
example, the BP 106 may generate the indicator signal 118
indicative of `LMR transmit enabled` to the CEM 102 and to the AP
104. The BP 106 may also generate the indicator signal 120
indicative of frequency band, such as `LMR frequency`, to the CEM
102 and to the AP 104. The `LMR Frequency` may specify the exact
LMR Frequency in use or a range of LMR frequencies that are
currently in use. In simultaneous operations, the second modem 110
generates the indicator signal 122 to the CEM 102 and the AP 104
indicative of the frequency band of operation, such as `LTE band`.
`The LTE` band` may specify the exact LTE frequency in use, or a
range of LTE Frequencies in use, for example Band 14 or Band 5.
[0015] In accordance with some embodiments, the indicator signals
118, 120, 122 are analyzed by the CEM 102 and the AP 104 for
interference. In response to detecting interference by the CEM 102,
the CEM drives a hardware attenuation enable line 126 to both the
AP 104 and the attenuation switch 112, thereby engaging the
attenuation switch 112 which serves to disconnect the second modem
110 from the second antenna 132. In response to the hardware
attenuation enable line 126 being enabled, the AP 104 performs
additional analysis to confirm the interference detected by the CEM
102. In some embodiments, a change in the indicator signals 118,
120, 122 will trigger this interference analysis. The AP 104 then
determines and performs an appropriate interference mitigation.
This mitigation will be performed after an optional holdoff timer
stage. The holdoff timer may be a configurable holdoff timer. The
AP validates that the interference is still present before applying
the interference mitigation. An example scenario would be during
LMR scan, in which the time spent in the interference scenario
would be shorter than the time required to engage the software
mitigation. In some embodiments, where the AP determines that
software mitigation is the appropriate interference mitigation, the
AP 104 then drives the software mitigation line 128 to the CEM 102.
In other embodiments, where AP 104 determines that power mitigation
is the appropriate interference mitigation, the AP 104 then
instructs the second modem 110 to perform a specific power level
interference mitigation, and the second modern 110 then drives a TX
Power Level line 124 to the CEM 102. In response to either the TX
power level signal 124 or software mitigation signal 128, the CEM
102 then releases the hardware attenuation enabled line 126 thereby
releasing the attenuation switch 112 in response to the
interference software mitigation being engaged.
[0016] The CEM 102 further detects changes in interference
conditions, such as via the indicator signals 118, 120, 122 and
instructs the AP 104 to disengage the interference mitigation, via
a release mitigation signal 138, when the interference is no longer
present. In some embodiments, a change in the indicator signals
118,120, 122 will trigger the AP to reevaluate if the interference
is no longer present. Prior to removing the mitigation, the AP may
apply a second holdoff timer to prevent mitigation thrashing
scenarios that may occur with LMR scan or trunking mobility. At the
completion of the second holdoff timer, the AP will remove the
mitigation, thereby returning the first and second modems 108, 110
to normal converged operation. For example, interference mitigation
can be removed in response to a frequency change by one of the
modems which negates the need for the interference mitigation.
[0017] In accordance with the embodiments, the interference
mitigation may comprise one or more of: power reduction to the
second modem; data throttling to the second modem; and/or band
steering of the second modem. For example, for the LMR/LTE
application, the interference mitigation may comprise one or more
of: power reduction to the LTE modem, reducing data speed to the
LTE modem, and/or band steering of the LTE modem. The band steering
may be performed for example, through dynamically disabling certain
LTE bands to steer the LTE modern to a non-interfering
location.
[0018] While examples are provided which refer to LMR and LTE
modems, it is to be appreciated that the embodiments can be applied
beyond LMR and LTE operations. The use of the baseband processor
106 and the LMR modem 108 is particularly advantageous to public
safety communication devices which support mission critical
communications. Such devices rely on mission critical push-to-talk
(PTT) and scan, hence the mitigation of interference from the LTE
modem 110 is extremely important. The applications processor 104
and the LTE modem 110 provide a plurality of non-mission critical
features such as text-to-speech, touch screen display features,
BLUETOOTH, WiFi, and/or global positioning system (GPS) to name a
few.
[0019] The portable communication device 100, when operating using
first and second frequency bands controlled by first and second
modems is able to detect and mitigate interference generated by
second modem transmit frequency bands conflicting with first modem
receive bands, external RF transmissions interfering with the
second modem, internal first modem transmissions interfering with
the second modem, and second modem transmit frequency bands
interfering with internally generated first modem transmissions.
For example, the portable communication device 100, when operating
using LMR and LTE frequency bands controlled by LMR and LTE modems
is able to detect and mitigate interference generated by: LTE
transmit frequency bands conflicting with LMR receive bands,
external LMR transmissions interfering with the LTE modem, internal
LMR transmissions interfering with LTE modem, and LTE transmit
frequency bands interfering with internally generated LMR
transmissions.
[0020] To address the LTE transmit frequency bands conflicting with
LMR receive bands and to address the LTE transmit frequency bands
interfering with internally generated LMR transmissions, the
mitigation approach comprises reducing power, and/or band steering,
and/or reducing data speed to the second modem in the manner
described previously.
[0021] Examples of potential interference may include but are not
limited to, the upper edge of LMR 700 MHz band (769 MHz-775 MHz)
which may be very close to the lower edge of LTE BAND 13 (Uplink
777 MHz-787 MHz) resulting in out of band emissions interference
when two transceivers are operating simultaneously. Another
example, in which frequencies overlap are LMR 800 MHz band (862
MHz-869 MHz) and LTE BAND 5 (Downlink 869 MHz-894 MHz). The
hardware mitigation provided by the CEM 102 to engage the
attenuation switch 112 provides instantaneous interference
protection while the software mitigation is executed. These
software mitigations can take hundreds of milliseconds to enact,
and relying on them without the hardware mitigation would result in
degraded LMR scan and mobility operations.
[0022] To address internal or external LMR transmissions
interfering with the LTE modem, the portable communication device
100 further comprises a radio frequency (RF) detector 134
operatively coupled to a receive input of the second antenna 132
for detecting unwanted RF signals associated with a specific LMR
frequency range that can interfere with or cause damage to the LTE
modern 1110. Although not shown, the RF detector 134 may
interoperate with RF filtering and voltage reference circuits known
in the field of RF detection. In the past, the presence of a strong
unwanted RF signal to the second antenna 132 could have damaged the
second modem 110 and/or cause interference to the second modem 110.
For example, the presence of a strong unwanted external RF signal
or internal inter-modulation artifacts being picked up by the
second antenna 132 could have damaged the second modem 110 and/or
cause interference to the second modem 110. The RF detector 134, in
response to a strong unwanted signal, generates an external power
detect signal 136 to the CEM 102 and to the AP 104. The CEM 102, in
response to the external power detect signal 136, drives the
hardware attenuation signal 126 thereby enabling the attenuation
switch 112 and disconnecting the LTE antenna from the LTE modern
thereby protecting the second modem 110 from damage or
interference. The switch 112 remains engaged until the external
power detect signal 136 changes to an acceptable level as
determined by the CEM 102, thereby ensuring that the second modem
110 remains undamaged. For example, the presence of, a strong LMR
signal at an LTE antenna is prevented from causing damage to the
LTE modem by having the CEM maintain the attenuation switch
engaged.
[0023] The coexistence module (CEM) 102 provided by the embodiments
takes into account the currently active first and second modems and
automatically applies respective mitigation only as needed under
the predetermined scenarios of concern. Portable communication
device 100 advantageously allows for fine adjustment of
predetermined modem transceiver parameters such as power level and
band operation. Implementation of the CEM 102 and attenuation
switch 112 in hardware advantageously avoids substantial delays
that would be experienced through a software only mitigation
approach. In many cases, the dynamically changing nature of the
communications protocol makes a software implementation impractical
or unrealizable.
[0024] FIG. 2 is a flowchart of a method 200 for managing
simultaneous modem operations in a portable communication device,
such as the converged portable communication device 100 of FIG. 1,
in accordance with some embodiments. The method 200 has been
illustrated in terms of LMR and LTE frequency bands, controlled by
separate modems for ease of description, however it is to be
appreciated that the method 200 is applicable to other modems
operating simultaneously in frequency bands susceptible to
interference.
[0025] The method begins at 202, with simultaneous operation of
first and second modems, such as first and second modems 108, 110,
respectively operating on first and second frequency bands. For
example, simultaneous LMR and LTE communications taking place using
LMR and LTE modems 108, 110 respectively, in a coexistence mode of
the portable communication device 100. When a change in frequency
band operation takes place at 204, for example a change in either
LTE band operation and/or LMR TX/RX and/or LMR band operation, the
method ensures operation of the first frequency band communications
(LMR band) remains normal. At 208, a check is made for detecting
interference during the coexistence mode. For example, the method
detects whether the LTE band operations have interfered with the
LMR band operations.
[0026] When interference is detected at 208, the method 200
proceeds by engaging an attenuation switch 112 to the antenna path
of the second modem at 210 to temporarily negate second frequency
band communications at 212. For example, the attenuation switch 112
can be used to temporarily negate LTE communications, while the LMR
modem which may be handling mission critical communications
operates normally.
[0027] At 214, the cause of interference is analyzed, by the
applications processor 104 and a determination is made as to
whether a mitigation action is possible. For example, the cause of
interference may be analyzed by the AP and CEM of FIG. 1 as
previously described. When a mitigation action is possible at 214,
the method 200 proceeds to a mitigation mode at 216. The mitigation
may be a software controlled mitigation comprising for example,
reduced power to the second modem and/or reduced data speed to the
second modem (the LTE modem) as determined at 218. The software
mitigation 218 may incorporate an optional holdoff timer as
previously described to cater for LMR scan and mobility operations.
When the applicable software mitigation has been completed at 218,
the method 200 proceeds by disengaging the attenuation switch at
220 and establishing communications using the applicable software
mitigation thereby re-establishing coexistence operations at 222.
For example the LTE modem may operate at restricted power and/or
speed while the LMR operations remain normal. Communications
continue in the mitigated coexistence mode returning to 204 to
await a frequency change or change in TX/RX state.
[0028] Returning back to 214, when the cause of interference is
analyzed and a determination is made that a software mitigation
action is not possible, the method 200 returns back to 204 to await
a frequency change or change in LMR TX/RX state. Here, the first
frequency band communication, such as the LMR communication,
operates normally while the second frequency band communication,
such as LTE communications, has been negated at 212.
[0029] Returning back to 208, when interference is no longer
detected in the mitigated coexistence mode, the attenuation switch
is disengaged at 230. The removal of software mitigation 232 may
incorporate an optional holdoff timer as previously described to
cater for LMR scan and mobility operations. Any previously applied
software mitigation is removed at 232, thereby allowing the second
frequency band operations, such as the LTE band communications, to
return to normal, non-mitigated operation at 234, while returning
to 204 to await changes in frequency change or change in LMR TX/RX
state.
[0030] The method and apparatus provided herein have beneficially
enabled coexistence by mitigating interference without
infrastructure interaction. The method and apparatus advantageously
allow for fine adjustment for specific transceiver parameters such
as power level, data throttling, and band steering.
[0031] The mitigation approach advantageously focus on band edges
and avoids the use of large filters that could result in increased
insertion loss across the band, as well as the cost and size
associated with such filters. Additionally, the mitigation approach
avoids the use of a software-only approach that can take hundreds
of milliseconds which would degrade LMR scan/mobility operations
that can be on the order of 50 ms.
[0032] While the AP and BP have been described in terms of
advantageously supporting converged operation of two different
modems, for example the LMR modem and the LTE modem, it is also to
be appreciated that the embodiments can be applied to communication
devices having more than two processors supported more than two
modems operating with nearby frequency bands that are susceptible
to RF interference. As such the embodiments can be said to apply to
a plurality of different modems supporting communication protocols
operating over different but nearby frequency bands which are
susceptible to interference with each other.
[0033] In the foregoing specification, specific embodiments have
been described. However, one of ordinary skill in the art
appreciates that various modifications and changes can be made
without departing from the scope of the invention as set forth in
the claims below. Accordingly, the specification and figures are to
be regarded in an illustrative rather than a restrictive sense, and
all such modifications are intended to be included within the scope
of the present teachings.
[0034] The benefits, advantages, solutions to problems, and any
element(s) that may cause any benefit, advantage, or solution to
occur or become more pronounced are not to be construed as a
critical, required, or essential features or elements of any or all
the claims. The invention is defined solely by the appended claims
including any amendments made during the pendency of this
application and all equivalents of those claims as issued.
[0035] Moreover in this document, relational terms such as first
and second, top and bottom, and the like may be used solely to
distinguish one entity or action from another entity or action
without necessarily requiring or implying any actual such
relationship or order between such entities or actions. The terms
"comprises," "comprising," "has," "having," "includes,"
"including," "contains," "containing" or any other variation
thereof, are intended to cover a non-exclusive inclusion, such that
a process, method, article, or apparatus that comprises, has,
includes, contains a list of elements does not include only those
elements but may include other elements not expressly listed or
inherent to such process, method, article, or apparatus. An element
proceeded by "comprises . . . a," "has . . . a," "includes . . .
a," or "contains . . . a" does not, without more constraints,
preclude the existence of additional identical elements in the
process, method, article, or apparatus that comprises, has,
includes, contains the element. The terms "a" and "an" are defined
as one or more unless explicitly stated otherwise herein. The terms
"substantially," "essentially," "approximately," "about" or any
other version thereof, are defined as being close to as understood
by one of ordinary skill in the art, and in one non-limiting
embodiment the term is defined to be within 10%, in another
embodiment within 5%, in another embodiment within 1% and in
another embodiment within 0.5%. The term "coupled" as used herein
is defined as connected, although not necessarily directly and not
necessarily mechanically. A device or structure that is
"configured" in a certain way is configured in at least that way,
but may also be configured in ways that are not listed.
[0036] It will be appreciated that some embodiments may be
comprised of one or more generic or specialized processors (or
"processing devices") such as microprocessors, digital signal
processors, customized processors and field programmable gate
arrays (FPGAs) and unique stored program instructions (including
both software and firmware) that control the one or more processors
to implement, in conjunction with certain non-processor circuits,
some, most, or all of the functions of the method and/or apparatus
described herein. Alternatively, some or all functions could be
implemented by a state machine that has no stored program
instructions, or in one or more application specific integrated
circuits (ASICs), in which each function or some combinations of
certain of the functions are implemented as custom logic. Of
course, a combination of the two approaches could be used.
[0037] Moreover, an embodiment can be implemented as a
computer-readable storage medium having computer readable code
stored thereon for programming a computer (e.g., comprising a
processor) to perform a method as described and claimed herein.
Examples of such computer-readable storage mediums include, but are
not limited to, a hard disk, a CD-ROM, an optical storage device, a
magnetic storage device, a ROM (Read Only Memory), a PROM
(Programmable Read Only Memory), an EPROM (Erasable Programmable
Read Only Memory), an EEPROM (Electrically Erasable Programmable
Read Only Memory) and a Flash memory. Further, it is expected that
one of ordinary skill, notwithstanding possibly significant effort
and many design choices motivated by, for example, available time,
current technology, and economic considerations, when guided by the
concepts and principles disclosed herein will be readily capable of
generating such software instructions and programs and ICs with
minimal experimentation.
[0038] The Abstract of the Disclosure is provided to allow the
reader to quickly ascertain the nature of the technical disclosure.
It is submitted with the understanding that it will not be used to
interpret or limit the scope or meaning of the claims. In addition,
in the foregoing Detailed Description, it can be seen that various
features are grouped together in various embodiments for the
purpose of streamlining the disclosure. This method of disclosure
is not to be interpreted as reflecting an intention that the
claimed embodiments require more features than are expressly
recited in each claim. Rather, as the following claims reflect,
inventive subject matter lies in less than all features of a single
disclosed embodiment. Thus the following claims are hereby
incorporated into the Detailed Description, with each claim
standing on its own as a separately claimed subject matter.
* * * * *