基于软件无线电的Turbo码编码通信系统实现

Turbo coded communication system implementation based on software defined radio

为保障和提高无线信道下的数据传输可靠性和灵活性,基于通用软件无线电外设(USRP)平台设计和实现了以Turbo码作为信道编码方案的通信系统。系统发射机可采用1/2或1/3码率的Turbo码对传输数据进行编码,接收机通过软解调方法和软输入软输出的Max-Log-MAP迭代译码算法获得编码增益。仿真与测试结果表明,采用Turbo码作为编码方案可有效对抗噪声和衰落,降低传输误比特率,进而提高无线通信系统的可靠性。此外,通过文件传输等应用,进一步验证了本系统的可行性。

In order to guarantee and improve the data transmission reliability and flexibility over wireless channel,a communication system using Turbo codes as channel coding scheme based on the universal software radio peripheral （USRP） platform is designed and implemented.At the transmitter,Turbo codes with rate of 1/2 or 1/3 can be chosen to encode the data being transmitted.At the receiver,soft-decision demodulation and soft-input soft-output Max-LogMAP iterative decoding algorithm are applied to obtain the coding gain.Simulation and test results demonstrate that the design of Turbo coding scheme can effectively combat noise and fading,reduce the transmission bit error rate,thus improving the communication system reliability.Besides,the design is applied to a file transfer application,which further verifies the feasibility of the system.