Abstract: Timing and frequency offset processing in sub-carriers is performed in an Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) receiver system. Sub-carriers are divided into two sub-sets, where the sub-sets contain an equal number of sub-carriers. Subsequently bad sub-carriers are removed, if present, from first sub-set of the sub-sets, and corresponding sub-carriers from a second sub-set of the sub-sets are also removed. Further, a phase difference on each sub-carrier from each sub-set is computed, and mean phase differences of each of the sub-sets are computed. Furthermore, frequency offset is computed by averaging the mean phase differences of the sets.

Abstract: A method and apparatus for estimating timing and frequency offsets in an ISDB-T and ISDB-TSB receiver. In different embodiments, the method comprises estimating timing and frequency offsets by different estimation processes; assigning weights to the timing and frequency offsets according to the channel condition; and calculating timing and frequency offsets using the estimates of timing and frequency offsets and the weights.

Abstract: A method of layer combining based on generating a look-up table in an Integrated Services Digital Broadcasting (ISDB) receiver includes obtaining a transmission parameter configuration, generating the look-up table based on the transmission parameter configuration, assembling a null transport stream packets and a valid transport stream packets from a plurality of layers of a multiplexing frame, and generating a completed transport packet stream using the look-up table. The receiver may generate the look-up table by at least one of generating the look-up table in real time or selecting from a look-up table set based on the transmission parameter configuration. The transmission parameter configuration may include at least one of a transmission mode, a guard interval, a modulation, and a coding rate. The look-up table may define an order of the null transport stream packets and the valid transport stream packets from the plurality of layers in the multiplexing frame.

Abstract: A method to design low complexity and low power echo and NEXT cancellers based on wordlength reduction technique is presented. A circuit architecture to implement echo and cancellers is also presented. The low complexity and low power design relies on the fact that a TH precoder can be viewed as an IIR filter with an input equal to the sum of the original input to the TH precoder and a compensation signal. The proposed design also relies on the fact that sum of the original input to the TH precoder and the compensation signal has finite levels, which can be represented in less bits than the original input of the echo and NEXT cancellers. An improved design by exploiting the statistics of the compensation signal is also proposed to further bring down the complexity and power consumption of these cancellers.

Abstract: The invention relates to techniques for implementing high-speed precoders, such as Tomlinson-Harashima (TH) precoders. In one aspect of the invention, look-ahead techniques are utilized to pipeline a TH precoder, resulting in a high-speed TH precoder. These techniques may be applied to pipeline various types of TH precoders, such as Finite Impulse Response (FIR) precoders and Infinite Impulse Response (IIR) precoders. In another aspect of the invention, parallel processing multiple non-pipelined TH precoders results in a high-speed parallel TH precoder design. Utilization of high-speed TH precoders may enable network providers to for example, operate 10 Gigabit Ethernet with copper cable rather than fiber optic cable.

Abstract: A method to design parallel TH precoders and a circuit architecture to implement parallel TH precoders have been presented. The parallel design relies on the fact that a TH precoder can be viewed as an IIR filter with an input equal to the sum of the original input to the TH precoder and a compensation signal. The parallel design also relies on the fact that the compensation signal has finite levels. Therefore, precomputation techniques can be applied to calculate intermediate signal values for all possible values of the compensation signal.

Abstract: A technique for segmented frame synchronization for Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) and Integrated Services Digital Broadcasting-Terrestrial Sound Broadcasting (ISDB-TSB) systems, wherein the method comprises receiving a wireless digital signal comprising an Orthogonal Frequency Division Multiplexing (OFDM) frame, further comprising ODFM symbols, in a receiver and wherein the receiver comprises a time de-interleaver, a bit de-interleaver, and a descrambler; filling memory of time de-interleaver and bit de-interleaver by the received wireless digital signal; determining an OFDM segmented frame boundary when memory of the time de-interleaver and bit de-interleaver are full; decoding bits from time de-interleaver and bit de-interleaver using a Viterbi decoder; outputting the Viterbi decoding bits from time de-interleaver and bit de-interleaver when the OFDM segmented frame boundary is detected; obtaining a segmented multiplexing frame boundary upon receipt of the first bit from the

Abstract: An apparatus, system, and method of performing adaptive frequency domain equalization in an Orthogonal Frequency Domain Multiplexing (OFDM) based communication system transmitting data information, wherein the method comprises receiving OFDM symbols comprising scattered pilots; obtaining channel estimates on every third bin of the scattered pilots in a frequency domain, wherein the channel estimates are obtained by performing an interpolation in a time domain across the received OFDM symbols; estimating an original channel based on the channel estimates, wherein the original channel in the time domain is estimated by applying a finite impulse response (FIR) low-pass filter in a frequency domain, wherein the FIR low-pass filter is adaptive according to a delay span of an original channel impulse response and is sufficiently wide to cover the delay span of the original channel impulse response; and dividing the received OFDM symbols by the channel estimate to obtain transmitted data information.

Abstract: A method of fast fading channel Fast Fourier Transform (FFT) trigger point tracking in an integrated services digital broadcasting (ISDB) receiver includes inputting a signal in a fading channel including N Orthogonal Frequency Division Multiplexing (OFDM) symbols, determining an average correlation result of a current time-domain sample of the signal and a previous time-domain sample taken previously of the signal, accumulating the average correlation result for at least one of the OFDM symbols, determining a peak of the average correlation result to obtain a peak position, and identifying the peak position as a trigger point of the input signal. The peak position may be compared with a first trigger point to generate a trigger point error signal. The first trigger point may be set at the middle of a guard of an OFDM symbol to generate the trigger point error signal.

Abstract: A method of layer combining based on generating a look-up table in an Integrated Services Digital Broadcasting (ISDB) receiver includes obtaining a transmission parameter configuration, generating the look-up table based on the transmission parameter configuration, assembling a null transport stream packets and a valid transport stream packets from a plurality of layers of a multiplexing frame, and generating a completed transport packet stream using the look-up table. The receiver may generate the look-up table by at least one of generating the look-up table in real time or selecting from a look-up table set based on the transmission parameter configuration. The transmission parameter configuration may include at least one of a transmission mode, a guard interval, a modulation, and a coding rate. The look-up table may define an order of the null transport stream packets and the valid transport stream packets from the plurality of layers in the multiplexing frame.

Abstract: A method of estimating a coarse frequency offset in a receiver includes providing at least one candidate frequency offset in Orthogonal Frequency-Division Multiplexing (OFDM) symbols having transmission and multiplexing configuration control (TMCC) bins and auxiliary channel (AC) bins, modulating the TMCC bins and AC bins using differential binary phase shift keying (DBPSK) modulation, estimating a phase difference between a first symbol and a second symbol for the candidate frequency offset of the TMCC and AC bins to obtain a resulting phase difference, correcting the resulting phase difference based on a difference between the candidate frequency offset and a Fast Fourier Transform (FFT) center bin to obtain a corrected phase difference, mapping the corrected phase difference to numeric numbers, and adding the numeric numbers for the candidate frequency offset to obtain a summation result. The numeric numbers correspond to at least one of +1 or ?1.

Abstract: Identifying a trigger point of at least one OFDM decoder includes correlating a first time-domain sample of the at least one OFDM symbol with a second time-domain sample of the at least one OFDM symbol, processing the first time-domain sample and the second time-domain sample in the first moving average filter to determine a channel impulse response, comparing at least one correlation value of a first biggest path in the channel impulse response and a second biggest path in the channel impulse response, and determining a channel length of the channel impulse response based on a time duration of the channel impulse response. The OFDM decoder includes a first moving average filter and a second moving average filter.

Abstract: A technique for estimating maximum Doppler frequency of a wireless signal in a wireless communication system, wherein the method comprises receiving a wireless signal; determining an impulse response of the received wireless signal; determining an auto-correlation function (ACF) value of the impulse response of the received wireless signal; determining a power spectrum density of said received wireless signal based on the ACF value; and selecting an algorithm for performing demodulation of the received wireless signal by utilizing the determined power spectrum density.

Abstract: Timing and frequency offset processing in sub-carriers is performed in an Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) receiver system. Sub-carriers are divided into two sub-sets, where the sub-sets contain an equal number of sub-carriers. Subsequently bad sub-carriers are removed, if present, from first sub-set of the sub-sets, and corresponding sub-carriers from a second sub-set of the sub-sets are also removed. Further, a phase difference on each sub-carrier from each sub-set is computed, and mean phase differences of each of the sub-sets are computed. Furthermore, frequency offset is computed by averaging the mean phase differences of the sets.

Abstract: A modified classical Viterbi decoder which can take extrinsic information and output hard decisions. A modified Viterbi decoder is provided comprising a branch metric unit, the unit having a calculator; and a processor adapted to compute a revised branch metric by combining the initial branch metric and an additional weight parameter. The modified classical Viterbi decoder computes a branch metric by summing an initial branch metric and the additional weight parameter.

Abstract: A method of TMCC information acquisition in an ISDB-T/TSB receiver comprises detecting coarse frequency offset in the receiver to identify bins that have TMCC information; and acquiring TMCC and symbol number information from the identified bins. The detecting process may be conducted using different methods and the acquiring process may be conducted using different methods. The TMCC information acquisition method saves memory space and provides enhanced performance by using coarse frequency offset to identify the bins that have TMCC information and obtaining the TMCC and symbol number information from the identified bins.

Abstract: A method and apparatus for estimating timing and frequency offsets in an ISDB-T and ISDB-TSB receiver. In different embodiments, the method comprises estimating timing and frequency offsets by different estimation processes; assigning weights to the timing and frequency offsets according to the channel condition; and calculating timing and frequency offsets using the estimates of timing and frequency offsets and the weights.

Abstract: A method to efficiently deal with FEXT crosstalk in wireline communication system via MIMO equalization is presented. A MIMO-DFE based receiver architecture is developed to demonstrate the advantage over the traditional receiver design. A MIMO structure for systems with TH precoding is also developed for 10GBASE-T application. The proposed architecture overcomes the limitation of the traditional schemes and achieves a better SNR performance and lower receiver complexity. The proposed method relies on the fact that FEXT inherently contains information about the symbols transmitted from the three far end transmitters and it can be viewed as a signal rather than noise. Therefore, MIMO techniques are applied to turn FEXT into a benefit for the receiver design.

Abstract: A method to efficiently deal with FEXT crosstalk in wireline communication system via MIMO equalization is presented. A MIMO-DFE based receiver architecture is developed to demonstrate the advantage over the traditional receiver design. A MIMO structure for systems with TH precoding is also developed for 10GBASE-T application. The proposed architecture overcomes the limitation of the traditional schemes and achieves a better SNR performance and lower receiver complexity. The proposed method relies on the fact that FEXT inherently contains information about the symbols transmitted from the three far end transmitters and it can be viewed as a signal rather than noise. Therefore, MIMO techniques are applied to turn FEXT into a benefit for the receiver design.

Abstract: A method to design low complexity pipelined Tomlinson-Harashima precoders and its associated circuit architectures have been described. The low complexity pipelined TH precoder design relies on the proposed low complexity precomputation based FIR filters. In the low complexity precomputation method for FIR filters, each multiplier is replaced with a multiplexer.