Motorola Corporation

Motorola Mobility LLC

Motorola Solutions, Inc.

Intel Corporation

Google Inc.

Hewlett-packard Development Company, L.p.

Gregory M Agami

Robert J Corke

Ron Rotstein

Yun H Kim

Jiangnan Jason Chen

Nathanael P Kuehner

Daniel G Prysby

Rodger W Caruthers

Stephen J Govea

Micah D Silberstein

David N Taylor

Yuda Yehuda Luz

Kadathur S Natarajan

Michael J Carney

Pablo Tacconi

George Powley

Stefan Paun

Yehuda Luz

Prachi P Kumar

Pierre Muratory

Ludovic Tancerel

Chris T Quanbeck

Vincent M Sciascia

Ronald Rotstein

Saten D Barve

Wei Chuan Ma

Victor Adut

Christophe Durand

Stephane Torres

Robert John Corke

Yehuda Y Luz

Jeffrey Kenline

Systems and methods for classifying radio frequency signal modulations include receiving, at a consolidated neural network, a complex quadrature vector of interest representative of a baseband signal derived from a radio frequency signal, generating multiple data representations of the vector of interest, providing each data representation to one of multiple parallel neural networks in the consolidated neural network, and receiving, from the consolidated neural network, a classification result for the baseband signal. The consolidated neural network may be trained to classify baseband signals with respect to known modulation types by receiving complex quadrature training vectors, each including samples of a baseband signal derived from a radio frequency signal of known modulation type, comparing a classification result for the training vector to the known modulation type to determine modulation classification performance, and modifying a configuration parameter of the consolidated neural network dependent on the determined modulation classification performance.

Systems and methods for modulation classification of baseband signals using multiple data representations of signal samples

Systems and methods for classifying baseband signals with respect to modulation type include receiving, at a consolidated neural network whose objective is modulation classification performance, a complex quadrature vector of interest including multiple samples of a baseband signal derived from a radio frequency signal of unknown modulation type, generating multiple data representations of the vector of interest, providing each data representation to one of multiple parallel neural networks in the consolidated neural network, and receiving a classification result for the baseband signal based on combined outputs of the parallel neural networks. The consolidated neural network may be trained to classify baseband signals with respect to known modulation types by receiving complex quadrature training vectors, each including samples of a baseband signal derived from a radio frequency signal of known modulation type, and comparing a classification result for the training vector to the known modulation type to determine modulation classification performance.

A method and user device are for communicating data from the user device by transmitting a synchronizing preamble having no timing advance, the synchronizing preamble comprising a base sequence that has been cyclically shifted by N shift index durations. The user device receives from a network station a response that indicates that a preamble was received from the user device having the base sequence cyclically shifted by N&#x2212;1 shift index durations. The user device determines, based at least partially on the response, that corrective action is appropriate. The user device performs one of transmitting a modified form of synchronizing preamble, transmitting the data as a data message having a timing advance, and barring further attempts to transmit the data to the network station for a defined duration.

Apparatus and method for data message communication

A method and system synchronizes transmission of receive data over an asynchronous digital radio frequency interface in a wireless communication device. A timing accurate strobe (TAS) re-sampler generates, using a first timing strobe synchronized to a baseband modem clock, a second timing strobe synchronized to a radio frequency integrated circuit (RFIC) clock. The TAS re-sampler forwards the second timing strobe to the RFIC to trigger a collection of data samples and initiates a count of RFIC clock cycles. The RFIC sends the data samples to a baseband First In First Out (FIFO) buffer over the asynchronous interface. In response to the count reaching a pre-determined number of RFIC clock cycles corresponding to a fixed delay, the TAS re-sampler triggers a reading of data from the FIFO buffer. The baseband modem receives data corresponding to the collection of data samples after a fixed delay from generation of the first timing strobe.

Synchronizing receive data over a digital radio frequency (RF) interface

A system includes a polyphase multirate filter and a controller which, responsive to detecting a data stream: measures a current phase relationship between a current resampling filter input clock signal and a current multirate output clock signal; identifies, based on a mapping of the measured phase relationship within a pre-generated quantized mapping table, an initial polyphase filter coefficient index corresponding to the measured phase relationship; selects, based on the initial polyphase filter coefficient index identified, a corresponding polyphase filter component from within the multirate filter; configures the multirate filter to pass data from the data stream through the corresponding polyphase filter component to generate an initial output data sample; updates the initial polyphase filter coefficient index to a calculated next polyphase filter coefficient index value, in response to a request for generation of a next output data sample; and self-corrects the multirate filter responsive to a pre-identified error condition.

Self-correcting multirate filter

An apparatus and method for uplink time synchronization in a communication system includes a first stepof receiving uplink data from a user equipment. A next stepincludes storing a time error of the uplink data along with a time stamp. A next stepincludes integrating the time error to provide an accumulated time error. A next stepincludes dumping the accumulated time error upon the time stamps of the accumulated data meeting a timing condition. A next stepincludes comparing the accumulated time error against a threshold. A next stepincludes scheduling a time advance with the user equipment if the accumulated time error exceeds the threshold.

Uplink time synchronization in a communication system

A method and apparatus for requesting bandwidth in a subscriber station is disclosed. The method dynamically changes the size of the bandwidth request based on the prediction of the number of packets needed to be transmitted. The average delay experienced by packets in a queue is measured, and this information is then used to change the coefficient of a prediction equation. When the experienced average delay is below the agreed upon QoS latency parameter or delay target, the method reduces the size of the bandwidth requests by making the prediction equation more conservative. On the other hand, when the experienced delay is above the agreed upon latency, the algorithm will make the prediction equation more aggressive, increasing the bandwidth requests and reducing the latency for future packets. By modifying the prediction equation based on the measured delay, the method is able to select the optimal point for achieving time delay requirements while preserving air-link resources.

Latency-aware adaptive bandwidth request mechanism for real-time communication in WiMAX

A wireless communication system that provides periodic channel quality feedback adjusts a channel condition reporting period for a subscriber station based on the multiple channel condition information reports, such as CQI messages, received from the subscriber station.

Method and apparatus for providing channel quality feedback in a wireless communication system

A method and apparatus includes a scheduling entity () for scheduling and transmitting the superframe () across a communication network (). The controller () coupled with scheduling entity () groups the subscriber unit () into one of the plurality of groups. The scheduler entity () assigns a coding scheme for each group and encodes each frame of the superframe () based upon the assigned coding scheme for the group, to which the frame is to be transmitted. The transceiver () coupled with controller () via hardware interface () receives the encoded superframe and transmits the superframe to the plurality of subscriber units in the communication network ().

Method and apparatus for transmitting a superframe across a communication network

A method and apparatus for complex multiplication includes steps of: (a) receiving a complex multiplicand having a real value and an imaginary value (); (b) generating a negation of the real value of the complex multiplicand (); (c) generating a negation of the imaginary value of the complex multiplicand (); (d) receiving a complex multiplier (); and (e) selecting a phasor constant having a value wherein a complex product of the complex multiplicand times the complex multiplier times the phasor constant has a real value equal to one of the real value of the complex multiplicand, the imaginary value of the complex multiplicand, the negation of the real value of the complex multiplicand, and the negation of the imaginary value of the complex multiplicand ().

Complex multiplication method and apparatus with phase rotation

A long code scrambler has been provided to scramble the data bits prior to QAM mapping. Different data rates are accommodated by using different long code m-tuples sampled at the modulation symbol rate, where m equals 2, 4 or 6 for 4, 16 or 64 QAM, respectively. In order to support 1XEV-DV users employing multiple Walsh code channels, a long code 6-tuple sample is permutated, to further randomize the QAM symbols. As appropriate for the modulation order, 2, 4 or 6 bits of the permutated 6-tuple are applied to the data sequence. That is, in addition to randomizing the modulation symbols for a given code channel, each code channel will likely have unique QAM symbols at any given symbol time.

Data transmission and reception within a spread-spectrum communication system

An automatic gain control includes a digital lowpass filter for filtering a series of digital samples generated by an analog-to-digital converter to generate a lowpass filtered digital sample series; a power averager coupled to the digital lowpass filter for calculating an average power of the lowpass filtered digital sample series; and a lookup table coupled to the power averager for setting a selectable gain of an amplifier coupled to the analog-to-digital converter as a function of the average power.

Automatic gain control with digital filtering for radio-frequency communications systems

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.

Method and apparatus for adaptive signaling in a QAM communication system

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. In addition, by including a second order timing recovery loop, the receiving communication device is able to quickly and precisely respond to drifting of a timing reference differential between itself and the transmitting communication device.

Method and apparatus for timing recovery in a communication device

A method, apparatus and system for use in determining a pilot-to-data power ratio by receiving a data symbol () having a data amplitude, receiving a pilot signal () having a pilot amplitude, reverse training () an automatic gain () based on the data amplitude and the pilot amplitude, and determining a pilot-to-data power ratio () according to the reverse training of the automatic gain. In some embodiments the method further compensates for channel fading in the data symbol by providing for channel correction () on the data symbol, providing for channel correction () on the pilot signal and dividing the channel corrected data symbol by the channel corrected pilot signal providing a fading compensated data symbol, where the fading compensated data symbol () is provided prior to reverse training such that the reverse training is based at least in part on the fading compensated data symbol.

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Arlington Heights, IL, United States of America

Gregory M Agami