On the Performance of NCC-OFDMA Systems in the Presence of Carrier Frequency Offset

Network coded cooperative (NCC) systems have recently gained increasing attention due to their high power and spectral efficiency. For high speed data transmission over frequency-selective channels, NCC is further combined with orthogonal frequency division multiple access (OFDMA). In this paper, we derive outage probability and diversity gain of NCC-OFDMA systems in the presence of carrier frequency offset (CFO). Our results demonstrate that NCC-OFDMA system is capable to achieve full spatial and frequency diversity in noise limited system where the CFO variance sigma(2)(epsilon) -> 0. However, in interference limited case where the CFO variance sigma(2)(epsilon) > 0, error floor occurs leading zero diversity gain. Numerical results are further presented to validate our analytical findings.