Motorola Corporation

Sr Technologies, Inc.

Motorola Mobility LLC

Other

Google Inc.

Blackberry Corporation

Xg Technology, Inc.

Stephen Rocco Carsello

Douglas I Ayerst

Bradley J Rainbolt

Warren P Glotzbach

Clinton C Powell, Ii

Douglas I Averst

Leo George Dehner

James Michael Keba

Mark A Goldberg

Tony R Branch

Joseph C Liberti, Jr

Metin Bayram

Steven Jeffrey Goldberg

Jheroen Pieter Dorenbosch

Eric Thomas Eaton

Weizhong Chen

Chin Pan Wong

John C Sinibaldi

Thomas A Sexton

Brian J Budnik

Chun-Ye Susan Chang

Damian Kelly Harris-Dowsett

Ronald A Craig

Anthony Rodrigues

Thomas Keller

Leo G Dehner, Jr

Dalier J Ramirez

Frank Earl

Xiang Liu

Caryn Chan

A method for detecting a preamble waveform of a received signal is described. The method includes dividing a correlation into a plurality of sub-correlations, for a plurality of frequency offset indices, k, covering a range of frequency offsets. The correlation has a correlation length equal to N, and a plurality of sub-correlations has a sub-correlations quantity equal to I, each sub-correlation of the plurality of sub-correlations has a sub-correlation length equal to M. A complex oscillation for a template frequency offset associated with k is approximated, the approximation is to be constant over an M-sample interval and is a piece-wise approximation. The approximated complex oscillation has length I. A quantity I of sub-correlations at each k is assembled using the approximated complex oscillation of length I. The method further includes determining that the received signal comprises the preamble based on the assembled sub-correlations and a correlation threshold.

Correlator bank for preamble detection

A method for detection of an orthogonal frequency division multiplex (OFDM) packet preamble is described. The method includes quantizing a real part and an imaginary part of each complex template value to a template index value, determining a plurality of non-zero template index values based on the quantization, receiving a signal including a plurality of samples, performing a plurality of first sums, where each first sum sums a sample subset of plurality of sample subsets, and assigning the plurality of non-zero template index values to the plurality of first sums. The method further includes performing a transposition of each first sum using the assigned non-zero template index value, performing a second sum, where the second sum is a complex weighted sum of the transposition of each first sum, and determining that the received signal comprises the OFDM packet preamble based on the complex weighed sum.

Orthogonal frequency division multiplex packet detection using the long preamble

A method and system are disclosed for blind decoding of Bluetooth packets. According to one aspect, a method of decoding packets includes detecting a packet using blind LAP detection. The method also includes estimating a duration of a payload of the packet and decoding a payload of the packet over the estimated duration according to each of a plurality of forward error correction (FEC) coding rates to produce a packet header. For each of a plurality of de-whitening seeds, the method includes performing de-whitening, extraction and reverse decoding on the packet header to produce a plurality of candidate upper address parts (UAPs). The method includes obtaining a subset of the candidate UAPs, each candidate UAP having a corresponding CRC code, and forming an ordered list of candidate packet types based at least in part on the estimated duration. The method includes performing a CRC to select a UAP.

Blind decoding of data packets

A method and receiver are disclosed for the blind detection and synchronization of data packets are disclosed. According to one aspect, a method includes generating a running histogram of received sample values for each of a plurality of frequency bins and symbol timing phases, the running histogram spanning a most recent block of symbols representing a candidate synchronization (sync) word. The method also includes, for each symbol interval: analyzing the histogram to estimate symbol timing phase, DC offset and frequency offset. The method also includes determining a first candidate sync word based at least in part on the symbol timing phase, frequency offset and corresponding DC offset the first candidate sync word representing a most recent vector of bits associated with the first candidate sync word. The method further includes discerning a lower address part (LAP) obtained from the first candidate sync word to enable detection of a packet.

Blind detection and synchronization of data packets

A multi-band synchronizer that performs robustly in the presence of partial-band interference by breaking down the correlation of a sync waveform at a plurality of times, with one or more received signal branches into a multitude of sub-band correlations, and combining the sub-band correlations such that the impact of partial-band interference on synchronization performance is significantly mitigated is disclosed.

Interference-tolerant multi-band synchronizer

A method at a mobile device, the method comprising: receiving one or more data symbols; determining reduced symbols for each of the data symbols, the reduced symbols corresponding to each of at least two orthogonal components of the data symbols; and, storing the reduced symbols in a symbol buffer.

Space and latency-efficient HSDPA receiver using a symbol de-interleaver

A method and apparatus for secure communication in a digital two way radio protocol is disclosed herein. The method includes the step of, at an originating radio, generating at least one control value (). The method further includes the step of generating an encryption key based on the at least one control value and a personal identification code at the originating radio (). The method further includes the steps of encrypting data traffic with the encryption key to provide encrypted data traffic at the originating radio (), transmitting the at least one control value to at least one target radio (), and transmitting the encrypted data traffic to the at least one target radio ().

Method and apparatus for secure communication in a digital two way radio protocol

A mobile communication device () includes a receiver () which is normally shut off when the mobile communication device is idle. Upon the arrival of a paging time slot to which the mobile communication device is assigned, the mobile communication device turns on the receiver and begins receiving a composite signal including frequency diverse subchannels. The mobile communication device measures the delay spread of the subchannels (). The receiver then adjusts the receiver on time for the next time slot based on the delay spread of the present time slot.

Method for reducing power consumption when receiving paging channel information at a mobile communication device

A system () and method () for peak limiting suitable for use in a communication system is provided. The method can include modulating () a symbol vector to produce a modulated waveform (), wherein the symbol vector contains at least one symbol in at least one subcarrier (), computing () at least one symbol adjustment that is based on at least one peak overshoot () of the modulated waveform, and applying () the at least one symbol adjustment to the symbol vector in accordance with an assigned weighting for reducing a peak power of the modulated waveform. The method limits an energy in the at least one subcarrier to a prespecified level of distortion.

Method and system for peak power reduction

A method (or) and system of reducing collisions in an asynchronous communication system can include the steps at a transmitter () of generating () a set of known preamble waveforms and transmitting () at least one distinguishable preamble waveform based on an association with a call type and a receiver identifier. The method () can also include the steps at a receiver () of receiving () at least one preamble waveform among a set of different preamble waveforms which toggle between two symbol frequencies, the different preamble waveforms being distinguishable by at least having one among a different symbol frequency spacing and a different symbol toggling duty cycle. The method further includes the step of selecting () to decode a preamble waveform based on at least one among the different symbol frequency spacing and the different symbol toggling duty cycle.

Method and system of reducing collisions in an asynchronous communication system

A receiver front end () receives a known Stop Waveform () comprising a predetermined symbol pattern on a voice channel, the Stop Waveform sent at the end of a transmission. A processor () coupled to the receiver front end terminates () the reception of the voice channel in response to detecting the Stop Waveform. The processor computes () a plurality of characteristics derived from the received signal, including a carrier-to-noise ratio, a maximum normalized symbol correlation energy over all symbols of the Stop Waveform, and a number of small and a number of large normalized symbol energy values. The processor detects () the Stop Waveform by comparing the plurality of characteristics with a corresponding plurality of predetermined thresholds.

Method and apparatus for terminating reception in a wireless communication system

The invention provides a method and apparatus for achieving timing synchronization during signal acquisition and for achieving frequency synchronization in a digital communication receiver after signal acquisition. The invention operates by performing multiple correlations of a received signal, each correlation performed over an symbol interval and correlating the received signal in the symbol interval with a sinusoid of an expected frequency. The correlations are combined to determine a peak and energy, and if the peak to energy ratio is above a threshold, the symbol timing and frequency offset is estimated.

Method and system for synchronizing in a frequency shift keying receiver

A processor () determines () a channel metric from a data signal received on a diversity branch. The processor calculates () an index into a final metrics buffer (), the index determined from a position of the channel metric within an interleaved frame of data. The processor places () a value derived from the channel metric into the final metrics buffer at a location defined by the index. A corresponding method and apparatus as well as communications receiver utilizing the processor () are described.

Method and apparatus for facilitating efficient deinterleaving and diversity-combining of a data signal

A wireless receiverand corresponding method to detect a message identifier or preamble that has been generated and provided by a transmitteruses FFTs to estimate frequency and time offset. The wireless receiverscans, asynchronously and sequentially during a wakeup time, a plurality of predetermined frequencies for the message identifier or specialized preamble. A plurality of received sample sequences are collected, one received sample sequence collected at each of the plurality of predetermined frequencies. A correlation between data corresponding to the preamble and data corresponding to a received sample sequence is compared to a threshold value to determine when the preamble has been detected. The wireless receiveris wakened from a low power mode when the preamble is detected.

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Plantation, FL, United States of America

Stephen Rocco Carsello