Signal receiver and signal receiving method for OTFS based mmWave communication systems having non-ideal power amplifier attributing nonlinear distortions in the signal

A receiver with nonlinear detector for Orthogonal Time-Frequency Space (OTFS) based mmWave communication systems involving non-ideal power amplifier, said receiver with nonlinear detector is configured to retrieve signal having nonlinear distortions including multiplicative distortion and inter symbol interference (ISI) resulting in intractable posterior distribution of delay-Doppler samples attributed by said non-ideal power amplifier and comprises

• antennas for receiving transmitted signal and passing the same to an analog beamforming unit;
• said analog beamforming unit to decouple the received signal into multiple parallel paths;
• at least one delay-Doppler domain unit for converting received time-domain signal after beamforming for each identified path into delay-Doppler domain with applicable nonlinear distortion;
• maximal ratio combining (MRC) unit with delay and Doppler compensating unit to yield nonlinearly distorted delay-Doppler domain OTFS sample {circumflex over (X)}(l, k);
• particle filter unit to approximate intractable distribution through particles and weights, which involves estimation of the ISI from passing the nonlinearly distorted delay-Doppler domain OTFS samples {{circumflex over (X)}(l, k)}k=0N-1 through a hard detector to obtain tentative decisions {{circumflex over (X)}(l, k)}k=0N-1 and converting the tentative decisions to time domain samples ŝ(n), whereby the ISI {circumflex over (ξ)}ŝ(l+k̆M)(k) is obtained from its expression, thus enabling Maximum A-posteriori Probability (MAP) detection to acquire the transmitted delay-Doppler samples estimate free of the ISI effect.