Parallel concatenated Gallager codes for reliable data transmission in cognitive radio networks

Abstract

Cognitive radio technology addresses the problem of spectrum scarcity by providing an opportunity for secondary users to exploit the unutilised licenced spectrum. However, constant interference from primary users makes reliable communication extremely challenging for secondary users in cognitive radio networks. Forward error correction codes ensure the reliability of transmitted data, among which low-density parity check codes are the most appropriate. Lengthy low-density parity check codes, however, have certain drawbacks specifically high encoding and decoding complexity. Parallel concatenated Gallager code addresses these issues. This paper evaluates the performance of various parallel concatenated Gallager codes in a dynamic and fragile cognitive radio network environment where the secondary users are prone to constant interference from the primary users. Simulation results affirms that proposed parallel concatenated Gallager codes outperform a dedicated low density parity check code of same frame length and code rate.