Efficient ARQ protocols with anti-jamming coding for cognitive radios

摘要

We introduce simple yet efficient automatic retransmission request (ARQ) protocols in conjunction with two types of anti-jamming coding techniques-rateless coding and piecewise coding-for protecting secondary users' data transmissions in cognitive radio systems. For piecewise coding, we propose to employ systematic codes to facilitate efficient selected retransmissions and design short codes to maximize secondary user throughput. For rateless coding, we consider a protocol that transmits new parity packets during retransmission and show that this scheme is stable if the jamming rate of the system is within a certain range. It is seen that for both anti-jamming coding schemes, the corresponding simple ARQ protocols provide significant improvement in secondary user throughput. Moreover, the piecewise coding together with its ARQ protocol offers similar or better throughput performance compared with the rateless coding counterpart, without incurring the stability issue.