Samsung Electronics Co., Ltd.

Ati Technologies Inc.

Qualcomm Incorporated

Advanced Micro Devices Corporation

Xiaoqiang Ma

Azzedine Touzni

Linbo Li

Kee-Bong Song

Chun Kin Au Yeung

Farrokh Etezadi

Jungwon Lee

Hyukjoon Kwon

Hongbing Cheng

Jason P Adams

Feng Huang

David E Lewis

Louis Giannini

Gillyoung Jung

A method and an apparatus in a multiple-input multiple-output (MIMO) wireless communication system are provided. A signal is received over a channel. The channel is decomposed into a plurality of virtual channels. Symbol detection is performed on each of the plurality of virtual channels. Values are obtained for the channel. Decoding is performed using the values to output a decoded symbol value of the received signal.

Method and apparatus for high rank multiple-input multiple-output (MIMO) symbol detection

An apparatus including a plurality of multipliers each configured to multiply correlations by a weight, wherein the correlations include a plurality of subsets of correlations, wherein the weight of each of the plurality of multipliers is uniquely different from the weights of at least two of the plurality of multipliers and the correlations; a summation processor configured to sum the weight multiplied correlations of the plurality of multipliers for time n, where n is an integer; and a coarse timing and coarse frequency processor configured to generate a coarse timing and a coarse frequency based on the sum.

Apparatus and method for coarse timing and frequency synchronization

A method and an apparatus in a multiple-input multiple-output (MIMO) wireless communication system are provided. A signal is received over a channel. The channel is decomposed into a plurality of virtual channels. Symbol detection is performed on each of the plurality of virtual channels using respective symbol detectors. At least one of the symbol detectors has a lower rank than that of the channel. Output from the symbol detectors is combined to obtain final log likelihood ration (LLR) values for layers of the channel. Decoding is performed using the final LLR values to output a decoded symbol value of the received signal.

A receiver of a modulated signal is presented. The receiver includes a synchronization detector configured to receive a signal indicative of the modulated signal that includes a synchronization header and a data payload, and to detect an end of the synchronization header. The synchronization detector is configured to generate a differential signal based on the signal, perform cross-correlation of the differential signal with a reference differential signal to generate a cross-correlation output, compare a first sample of the cross-correlation output at a sample index associated with a hypothesized start frame delimiter (SFD) peak index with a second sample of the cross-correlation output at a sample index associated with a hypothesized preamble peak index, and detect an end of the synchronization header in response to a comparison result in which a magnitude of the first sample is greater than a magnitude of the second sample of the cross-correlation output.

System and method of detecting end of synchronization header of modulated signals

The apparatus includes a plurality of correlation processors configured to each receive a group of samples and generate correlations of each group of samples; a plurality of multipliers each configured to multiply the correlations of one of the plurality of correlation processors by a weight, wherein the weight of at least one of the plurality of multipliers is different from the weight of at least another one of the plurality of multipliers; a summation processor configured to sum the weight multiplied correlations of the plurality of multipliers for time n, where n is an integer; and a coarse timing and coarse frequency processor configured to generate a coarse timing and a coarse frequency based on the sum.

According to an embodiment of the present disclosure, a receiver of modulated signals comprises a signal mixer, a synchronization detector, and a data demodulator. The signal mixer is configured to perform baseband down-conversion of a signal according to a mixer frequency, the signal including a synchronization header and a data payload. The synchronization detector is configured to: generate a differential signal based on the signal, perform cross-correlation of the differential signal with a reference differential signal to generate a cross-correlation output, and analyze the cross-correlation output to detect an end of the synchronization header. The data demodulator is configured to demodulate the data payload in response to detection of the end of the synchronization header.

System and method of performing initial timing synchronization of receivers of modulated signals

According to an embodiment of the present disclosure, a receiver of modulated signals comprises a signal sampling unit configured to sample a signal, a zero-crossing demodulator, and a timing offset tracking unit. The zero-crossing demodulator includes: a zero-crossing counter configured to determine a number of zero crossings for each pulse of the signal, and a symbol selector configured to decode a sequence of pulses as a symbol based on the number of zero crossings in the sequence of pulses. The timing offset tracking unit is configured to: calculate a metric based on an accumulation of the number of zero crossings and corresponding pulse values of the decoded symbol, compare the metric to a predetermined threshold value, and compensate a timing offset of the signal by causing the signal sampling unit to sample the signal at an earlier interval or a later interval in response to the comparison.

System and method of tracking and compensating for frequency and timing offsets of modulated signals

A method and apparatus are disclosed for determining the presence of adjacent channel interference. Received digital signals are processed to detect the existence of strong channels adjacent to the channel of interest and control signals may be generated based on the detection of strong adjacent channels. The control signals are then used to adjust the signal power of the received signals.

Adjacent channel power scan

A receiver for receiving an orthogonal frequency division multiplexed (OFDM) digital video broadcast (DVB) signal including OFDM symbol sets including data symbols and pilot symbols transmitted using a plurality of sub-carriers, the OFDM DVB signal being transmitted toward the receiver via a transmission channel, the receiver including an input module configured to receive the OFDM DVB signal via the transmission channel, and a channel estimation module coupled to the input module and configured to calculate channel estimates of the transmission channel by performing Fourier transforms on the OFDM symbol sets to produce transformed symbol sets in the frequency domain and by performing minimum mean square error (MMSE) equalization on the transformed symbol sets using a sub-set of the pilot symbols in the OFDM DVB signal.

OFDM channel estimation

A method for synchronizing a receiver to a received signal begins by down-converting the received signal to a first baseband signal. A coarse frequency offset (CFO) of the first baseband signal is determined and is applied to the down-converting of the received signal to a second baseband signal. A fine frequency offset (FFO) of the second baseband signal is determined. The receiver is synchronized to the received signal using the CFO and the FFO.

Synchronization and acquisition for mobile television reception

A receiver for receiving an orthogonal frequency division multiplexed (OFDM) digital video broadcast (DVB) signal including OFDM symbol sets including data symbols and pilot symbols transmitted using a plurality of sub-carriers, the OFDM DVB signal being transmitted toward the receiver via a transmission channel, the receiver including an input processor configured to receive the OFDM DVB signal via the transmission channel and to perform a Fourier transform on the OFDM DVB signal to provide a frequency-domain signal, a channel estimation processor coupled to the input processor and configured to calculate final channel estimates, the channel estimation processor being configured to perform time-domain prediction on the frequency-domain signal to provide established sub-carriers that each have corresponding initial channel estimates, and perform minimum mean square error (MMSE) equalization on the frequency-domain signal using the initial channel estimates that correspond to a sub-set of the established sub-carriers to calculate the final channel estimates.

A method of signal processing according to an embodiment includes estimating a response of a transmission channel during a symbol period. Based on an estimated response of the transmission channel, components of a model of a phase noise process during the symbol period are estimated. Based on the phase noise process model, an estimate of a symbol received during the symbol period is obtained.

Systems, methods, and apparatus for phase noise mitigation

A method among the embodiments includes calculating a value of a parameter of a nonlinear model of a signal as transmitted into a transmission channel, and applying the calculated value to obtain an estimate of data values carried by the signal. Applications to multicarrier signals are described.

Systems, methods, and apparatus for mitigation of nonlinear distortion

A method of signal processing according to one of several embodiments includes estimating a deterministic component of a received signal. The estimating is based on an estimated response of a transmission channel. Based on the estimated deterministic component, a non-deterministic component of the received signal is estimated. Based on corrupted portions of the estimated non-deterministic component, a noise estimate is obtained, and the received signal is compensated based on the noise estimate. A method according to another embodiment includes replacing received samples at corrupted locations with values from a calculated model.

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Newtown, PA, United States of America

Xiaoqiang Ma