Receiver Algorithm based on Differential Signaling for SIMO Phase Noise Channels with Common and Separate Oscillator Configurations

摘要

In this paper, a receiver algorithm consisting of differential transmissionand a two-stage detection for a single-input multiple-output (SIMO) phase-noisechannels is studied. Specifically, the phases of the QAM modulated data symbolsare manipulated before transmission in order to make them more immune to therandom rotational effects of phase noise. At the receiver, a two-stage detectoris implemented, which first detects the amplitude of the transmitted symbolsfrom a nonlinear combination of the received signal amplitudes. Then in thesecond stage, the detector performs phase detection. The studied signalingmethod does not require transmission of any known symbols that act as pilots.Furthermore, no phase noise estimator (or a tracker) is needed at the receiverto compensate the effect of phase noise. This considerably reduces thecomplexity of the receiver structure. Moreover, it is observed that the studiedalgorithm can be used for the setups where a common local oscillator orseparate independent oscillators drive the radio-frequency circuitriesconnected to each antenna. Due to the differential encoding/decoding of thephase, weighted averaging can be employed at a multi-antenna receiver, allowingfor phase noise suppression to leverage the large number of antennas. Hence, weobserve that the performance improves by increasing the number of antennas,especially in the separate oscillator case. Further increasing the number ofreceive antennas results in a performance error floor, which is a function ofthe quality of the oscillator at the transmitter.