8 Antenna Polar Switching Up-Down Relay Networks

Abstract

In this paper, we propose a reliable <TEX>$8{\times}8$</TEX> up-down switching polar relay code based on 3GPP LTE standard, motivated by 3GPP LTE down link, which is 30 bps/Hz for <TEX>$8{\times}8$</TEX> MIMO antennas, and by Arikan's channel polarization for the frequency selective fading (FSF) channels with the generator matrix <TEX>$Q_8$</TEX>. In this scheme, a polar encoder and OFDM modulator are implemented sequentially at both the source node and relay nodes, the time reversion and complex conjugation operations are separately implemented at each relay node, and the successive interference cancellation (SIC) decoder, together with the cyclic prefix (CP) removal, is performed at the destination node. Use of the scheme shows that decoding at the relay without any delay is not required, which results in a lower complexity. The numerical result shows that the system coded by polar codes has better performance than currently used designs.