Abstract: A method and apparatus to adaptively puncture bits within QAM modulated data symbols transmitted in a communication system in order to effect a signaling channel. The method and apparatus utilize inherent characteristics of a particular mapping scheme for the QAM constellation to selectively puncture particular bits within a data symbol with signaling information and predetermined binary values to selectively increase the log-likelihood ratio gains of those particular bits punctured with the signaling information. The log-likelihood ratios are used to obtain the signaling information and, thus, increasing the gain of the log-likelihood ratios affords greater reliability for the signaling information without increasing the required system resources.
Type:
Grant
Filed:
June 1, 2001
Date of Patent:
June 7, 2005
Assignee:
Motorola, Inc.
Inventors:
Gregory Agami, Robert John Corke, Ron Rotstein
Abstract: A control circuit for a feed forward amplifier provides for pausing control and continuous adjustment of a control signal, provides for the control signal to start at any point, provides for rapid convergence, and that does not perturb the system up or down one step to confirm the convergence of the system. The control circuit receives a sampled version of a feed forward amplifier output signal, generates a non-offset control signal based on the sampled output signal, separately generates an offset voltage by reference to voltages stored in a table or based on the non-offset control signal, and combines the non-offset control signal with the offset voltage to produce a control signal. The feed forward amplifier may then adjust an error signal based on the control signal to produce an adjusted error signal that is capable of reducing distortion in the feed forward amplifier.
Abstract: A receiving communication device synchronizes to a timing reference of a transmitting communication device based on a determined timing error. The receiving communication device determines the timing error by processing a synchronization signal via a first stage filtering and interpolation process that includes predetermined coefficients and a second stage interpolation process that includes a minimal number of dynamically determined coefficients. By dividing the process into a predetermined coefficient stage and a dynamically determined coefficient stage, the receiving communication device is able to make timing adjustments in a more efficient manner, that is, at a lesser processor loading, than a communication device in which all filtering and interpolation coefficients are dynamically determined.
Type:
Grant
Filed:
March 28, 2001
Date of Patent:
April 12, 2005
Assignee:
Motorola, Inc.
Inventors:
Gregory Agami, Robert John Corke, Ron Rotstein, Daniel G. Prysby
Abstract: Power control bit generation for forward link power control in a spread spectrum communication system is accomplished through modification of a set point threshold. Modification of the set point reduces the number of squaring and division mathematical operations, thus more efficiently utilizing limited system resources in a mobile receiver used in forward link power control.
Type:
Grant
Filed:
October 31, 2000
Date of Patent:
February 15, 2005
Assignee:
Motorola, Inc.
Inventors:
Michael M. Wang, Louay A. Jalloul, Tyler Brown
Abstract: A spreader (216) comprises a code generator (301) and exclusive OR circuitry (303). In the preferred embodiment of the present invention the code generator (301) generates a code having a length and value dependent upon the current transmission rate. This code is then exclusive OR'd with the incoming data stream to produce spread data.
Type:
Grant
Filed:
February 14, 2001
Date of Patent:
December 28, 2004
Assignee:
Motorola, Inc.
Inventors:
Lee Proctor, William K. Morgan, Mark Hetherington, Naisum Wong
Abstract: The present invention provides a method and apparatus for utilizing existing systems and components in a cellular network for managing network functionality to reduce event pressure between managers and agents. In accordance with the preferred embodiments of the invention, a filter, an event counter module, and a performance measurement module, all residing on the agent, perform event notification filtering, counting, and thresholding in the agent. In accordance with the preferred embodiments, only an alarm is sent to the manager from the agent if event notifications exceed a threshold that is established by the manager on the agent.
Abstract: A transmitter that includes a feed forward amplifier amplifies an input signal to produce an amplified signal that includes a distortion component. The transmitter determines an error signal based on the input signal and the amplified signal and amplifies the error signal to produce an amplified error signal that includes an error signal distortion component. The transmitter combines the amplified error signal with the amplified signal to produce an output signal that includes the error signal distortion component and a portion of the amplified signal distortion component. The transmitter determines a distortion component of an attenuated version of the output signal and an energy of the determined distortion component. Based on the determined energy, the transmitter produces a control signal designed to minimize the energy of the distortion component of the attenuated output signal and thereby minimize distortion in the output signal.
Type:
Grant
Filed:
April 19, 2001
Date of Patent:
November 16, 2004
Assignee:
Motorola, Inc.
Inventors:
Edward Vincent Louis, Michael David Leffel
Abstract: An apparatus (200) checks voice quality when in a vocoder bypass mode. If the voice quality level is beyond an acceptable range, the apparatus (200) ends the vocoder bypass mode and returns to tandem vocoding. For example, a vocoder bypass controller (206) includes a speech quality detector (225) that determines the speech quality level of speech information based on at least one of detected volume level, echo level and noise level of the speech information. The vocoder bypass controller (206) with the speech quality detector (225) outputs a speech quality-based vocoder bypass control signal (236) to selectively activate or deactivate a vocoder bypass operation in response to the speech quality-based vocoder bypass control signal (236). In another embodiment, a network element for communicating speech packets includes an incoming decoder (512) and a speech quality detector (514) operative to determine the speech quality level of incoming speech packets.
Type:
Grant
Filed:
October 31, 2000
Date of Patent:
August 31, 2004
Assignee:
Motorola, Inc.
Inventors:
Mansour Tahernezhaadi, J. Douglas Brophy, Lee M. Proctor, Michael J. Kirk
Abstract: A method and apparatus provide for soft handoff operation of at least a first signal transmitted according to a first communication standard (IS-95B) and a second signal transmitted according to a second communication standard (IS-95C).
Type:
Grant
Filed:
April 7, 2000
Date of Patent:
July 27, 2004
Assignee:
Motorola, Inc.
Inventors:
Louay Jalloul, Keith A. Tenbrook, Yuda Yehuda Luz, Jiangnan (Jason) Chen, Ron Rotstein
Abstract: An electronic component assembly includes an electromagnetic interference (EMI)-producing component capable of generating EMI and an EMI-sensitive component. The electronic component assembly further includes a radiation shunt disposed proximate to the EMI-sensitive component capable of attracting at least a portion of the EMI and, by attracting the at least a portion of the EMI, shielding the EMI-sensitive component from the at least a portion of the EMI. By providing a radiation shunt to shield the EMI-sensitive component, a need is reduced for a mechanical shield that surrounds the EMI-sensitive component.
Abstract: A wireless communication system that includes an MS that is a member of multiple talkgroups provides for a prioritization of the multiple talkgroups. A database included in the system maintains an MS identifier associated with the MS and maintains multiple talkgroup identifiers in association with the MS identifier, wherein each talkgroup identifier of the multiple talkgroup identifiers corresponds to a talkgroup of the multiple talkgroups. The database further maintains a prioritization associated with at least one talkgroup of the multiple talkgroups. In one embodiment of the invention, the MS may dynamically prioritize the multiple talkgroups to which it belongs. In another embodiment of the present invention, the prioritization may be statically maintained. In still another embodiment of the invention, the system utilizes the maintained prioritizations to determine whether to interrupt the MS when the MS is involved in a multi-party communication session.
Type:
Grant
Filed:
July 2, 2002
Date of Patent:
July 13, 2004
Assignee:
Motorola, Inc.
Inventors:
Tracy L. Wolf, Paul M. Erickson, John C. Stanaway, Peter M. Drozt, Steven E. VanSwol
Abstract: A base station (1) in a radio communication system is provided with an antenna array 2, 3 for communication with a plurality of mobile stations (4, 5). The transmissions of the base station (1) are optimised by adjusting the phase between the signals transmitted by each antenna (2, 3) so that the product of the propagation channel estimates is maximised. The invention has particular application to CDMA-TDD modes of operation where it has been shown to perform favourably in comparison with known transmit diversity techniques. A further advantage is that it does not require added complexity in the channel estimation at each mobile station (4, 5).
Type:
Grant
Filed:
February 22, 2000
Date of Patent:
July 13, 2004
Assignee:
Motorola, Inc.
Inventors:
Yann Farmine, Oscar Clop, Nicholas Whinnett
Abstract: A transmitter includes a feed forward amplifier that includes main signal path having a radio frequency (RF) power amplifier, a feed forward correction circuit, and a control circuit. An amplification of an input signal by the RF power amplifier produces an amplified signal that includes a distortion component. The feed forward correction circuit produces an error signal, which error signal is used to drive an error amplifier to produce an amplified error signal. In order to minimize a distortion component introduced to the amplified error signal by the error amplifier, the control circuit controls a peak power of the error signal based on a detected energy of an attenuated version of the error signal or based on the distortion component introduced to the amplified error signal by the error amplifier.
Type:
Grant
Filed:
April 19, 2001
Date of Patent:
June 1, 2004
Assignee:
Motorola, Inc.
Inventors:
Edward Vincent Louis, Michael David Leffel
Abstract: In a linear amplification system, an input signal is amplified to produce a substantially linear amplified output signal without causing significant intermodulation distortion or spectral growth. An envelope detector determines an envelope detector voltage from the input signal. A tracking power supply determines a supply voltage based on the envelope detector voltage. An input signal conditioner determines, in response to the supply voltage, a corresponding phase adjustment and a corresponding gain adjustment and modifies the input signal using the corresponding phase adjustment and the corresponding gain adjustment to produce a conditioned input signal. A power amplifier operates using the supply voltage and amplifies the conditioned input signal to produce the amplified output signal.
Abstract: A radio frequency (RF) power amplifier device that includes an RF amplification element coupled to an output matching circuit further includes a match extender that provides an extension of the output matching circuit beyond the RF power amplifier device. The match extender provides an apparatus by which the circuitry of the output matching circuit may be extended outside of the RF power amplifier device and by which output matching circuitry external to the RF power amplifier device may provide a matching impedance that originates at a die plane of the RF amplification element.
Abstract: An optimal operating point of an envelope tracking amplification system that includes a radio frequency (RF) power amplifier having an RF amplifying element is determined based on an application to the RF power amplifier of a supply voltage that is less than the rated voltage of the RF amplifying element.
Abstract: A communication system 100 acquires band class information and assigns a band class to MS 102 when the MS is engaged in a process of initiating a connection with infrastructure 104. The MS informs the infrastructure of the MS's band class capabilities when the MS initially performs an access attempt with the infrastructure in a reveres link associated with a first band class, that is, on r-csch 142 in reverse link 140. When the band class where the MS initially attempts access is congested, or the infrastructure desires to switch the MS to a second, alternate band class for any other reason, the infrastructure is able to immediately determine the band classes supported by the MS and to immediately assign the MS to a f-csch 132 or traffic channel 134 in a forward link 130 that is associated with the second, alternate band class supported by the MS.
Abstract: A method and apparatus for system time alignment is provided. The method and apparatus for a system time alignment provides synchronization between system components even when one or more system components remains in a quiescent mode for an extended period of time. Compensation for changes in propagation delay between system components is provided, even when such changes in propagation delay occur while one or more system components is in a quiescent mode. A searcher (402) searches a raw data signal for a maximal energy, and a shifter (403) shifts a spreading sequence a plurality of times. An accumulator (408) accumulates a plurality of sets of symbols to produce a plurality of symbol energies. A time offset calculator (410) calculates an updated time offset value and an updated system time value and updates a reference position counter (202) and a system time counter (205), respectively, with these values.
Type:
Grant
Filed:
May 23, 2000
Date of Patent:
April 6, 2004
Assignee:
Motorola, Inc.
Inventors:
Roy Xun Yang, Stefan Paun, Jiangnan Jason Chen
Abstract: A wireless communication system (100) employs a method and apparatus for providing information to multiple communication units (121-129). The communication system includes a communication infrastructure (101, 102, 103, 105, 111-113, 120), a data network (107) and an information source (109). The multiple communication units each subscribe to an information service provided by the information source. The communication infrastructure creates a subscription group that includes the multiple communication units. The infrastructure receives subscriber information including at least one information unit from the information source and sets up a point-to-multipoint group call with the subscription group. The infrastructure then transmits the subscriber information to the multiple communication units. Any information unit not confirmed by the multiple communication units is re-transmit by the infrastructure.
Abstract: A feed forward amplifier performs a carrier cancellation tuning process separate from an IM reduction tuning process, wherein the carrier cancellation tuning process is performed without reference modulations that are utilized to modulate a feed forward amplifier input signal during the IM reduction tuning process. By decoupling the reference modulations during the carrier cancellation process, the feed forward amplifier is able to eliminate the instantaneous carrier cancellation degradation that would otherwise be caused by the reference modulations.
Type:
Grant
Filed:
September 17, 2002
Date of Patent:
March 2, 2004
Assignee:
Motorola, Inc.
Inventors:
Wentian Zhang, Bryan Todd Irons, Mark Ian Van Horn