Receiver with prefiltering for discrete fourier transform-spread-orthogonal frequency division multiplexing (DFT-S-OFDM) based systems

A receiver for discrete Fourier transform-spread-orthogonal frequency division multiplexing (DFT-S-OFDM) based systems, comprising:

• a prefilter for demodulating one of a received signal codeword and received signal codewords;
• and
• a log-likelihood ratio LLR module responsive to the prefilter,
• wherein the prefilter includes a pairing and whitening module that, based on channel estimates and a data rate, enables the LLR module to perform either a Serial-In-Serial-Out (SISO) based log likelihood ratio processing of an output from the pairing and whitening module or a two-symbol max-log soft output demodulator (two-symbol MLSD) based log likelihood ratio processing of the output from the pairing and whitening module, the pairing and whitening module electing to process an input received from an inverse discrete Fourier transform (IDFT) module when the LLR module is enabled to perform the two-symbol MLSD based log likelihood ratio processing.

A receiver for discrete Fourier transform-spread-orthogonal frequency division multiplexing (DFT-S-OFDM) based systems, comprising:

• a prefilter for demodulating one of a received signal codeword and received signal codewords;
• and
• a log-likelihood ratio LLR module responsive to the prefilter,
• wherein the prefilter includes a pairing and whitening module that, based on channel estimates and a data rate, enables the LLR module to perform either a Serial-In-Serial-Out (SISO) based log likelihood ratio processing of an output from the pairing and whitening module or a two-symbol max-log soft output demodulator (two-symbol MLSD) based log likelihood ratio processing of the output from the pairing and whitening module, the prefilter including a per-tone equalizer for one of the received signal codeword and received signal codewords and an inverse discrete Fourier transform IDFT module responsive to the equalizer, the pairing and whitening module being responsive to the IDFT module.