The Application & Research Of Spinal Code In Short Wave Communication System

Spinal code is a kind of fountain codes,it can reach Shannon limit in AWGN & BEC channel and has an excellent communication performance in deep space channel.This paper try to apply Spinal code to HF channel to research its appropriateness used in short wave channel,especially in occasions when signals are heavily affected by fast fading effect & multi-user effect.Firstly the brief history of the development of error correction coding technology and its application in HF channel is introduced in this paper.Then,by analyzing some problems in process of Spinal coding,this paper made improvements about the end part of coding sequence thus makes the coding gain can increase about 0.2～0.3d B in AWGN channel.LDPC & Raptor code are taken by this paper as the reference to compare the communication performance with Spinal code in AWGN、short wave、FH & fast fading channel respectively.Experimental results show: in AWGN & slow fading HF channel,the overall communication performance of Spinal code is apparently inferior to LDPC code but still better than Raptor code;In fast fading channel & FH channel simulated by this paper,instead,Spinal code's overall communication performance is obviously better than the other 2 codes and has a much bigger channel capacity.for example,Spinal code's coding gain is 4d B more than Raptor code when BER is around,due to the relatively long code length and its coding structure,LDPC code's communication performance is the worst in FH channel and its BER curve stays above and didn't have a clearly trend to fall after SNR exceeds 8d B.In fast fading channel,the BER curve of Raptor code can get very close to Spinal code after SNR exceeds about 14 d B,and the Spinal code can obtain about 2d B coding gain if we increase the retransmission times by 2 every time.On the other hand,LDPC code's BER still stays high above even if SNR exceeds 20 d B and its BER curve go down very slowly compared to the other 2 fountain codes.This paper do researches about Spinal code in background of HF channel,with the improvements we did to Spinal code,Spinal code shows an obvious advantage over the other 2 coding references in channels which have strong time-varying characteristics.and the whole work been done in this paper undoubtedly offers another possible high performance coding scheme in HF channel.