Iterative multiuser detection with physical layer network coding for multi-pair communications

The physical layer network coding (PNC) technique has been utilized for increasing the system throughput in a two-way relay channel (TWRC) where the two users exchange their information via a relay node. In this paper, we investigate the effectiveness of increasing the number of users for the PNC technique where multiple pairs of users swap their information simultaneously through a single relay node for TWRC. This scheme relies on the iterative multiuser technique for detection of users at the receiver. Moreover, a common chip-level interleaver is shared for each pair of users wanting to exchange information. The performance of the proposed system is evaluated in term of bit error rate (BER) for iterative manner compared without iterative detection and the system shows the ability to increase the number of users. Moreover, the new scheme offers improved performance about 10 dB of signal to noise ratio (SNR) compared to the scheme without iterative detection to achieve a target BER of 10
^-3
over Rayleigh fading channel.