Performance Analysis of SCB-Spinal Code in Free-Space Optical Communication

Aiming at the problems of high decoding complexity and unequal error protection of Spinal codes in free space optical communication, a SCB-Spinal code scheme is proposed, in which cyclic redundancy code (CRC), Spinal codes, and BCH codes are concatenated. Premature termination of the segmented CRC check reduces the amounts of decoding calculations and the complexity of decoding, and also cascades the BCH code at the tail to perform error correction protection for error prone tail information. The simulation results show that the SCB-Spinal code effectively reduces decoding complexity and obtains better hit error rate performance under different turbulence intensities. Compared to the traditional Spinal code, the SCB-Spinal code is approximately 62% lower with respect to signal-to-noise ratio and turbulence. In addition, it exhibited a performance rate of 0.04-0. 17 bit/symbol. With respect to moderate and strong turbulence intensities, the complexity under SCB Spinal code is reduced by 50%-60%, facilitating efficient application of Spinal code in free space optical communication.