星地高速数传系统低复杂度可重构LDPC编码器设计

Low Complexity and Reconfigurable LDPC Encoder for High-speed Satellite-to-ground Data Transmissions

为满足近地轨道(LEO)卫星星地高速数传系统对高通量、低复杂度、高可靠性信道编码的应用需求,该文提出一种基于国际空间数据系统咨询委员会(CCSDS)近地卫星通信标准低密度奇偶校验(LDPC)码的低复杂度可重构编码器设计实现方案。通过对输入信息比特插0处理和拆分循环矩阵,并分析不同并行度编码的结构特点,实现了可重构编码方案,提高了编码器的灵活性和编码数据吞吐率;采用优化的移位寄存器累加单元,降低了编码器的整体硬件资源规模。在Xilinx FPGA上对提出的编码器进行了实现,结果表明,在125 MHz系统工作时钟下,编码数据吞吐率最高可达1 Gbps,归一化编码数据吞吐率与其它文献并行度相近的编码器相比提高了17.1%,其寄存器资源和查找表资源与相同平台已有方案相比分别降低了13.7%和14.8%。

A new low complexity and reconfigurable Low Density Parity Check(LDPC)encoder design based on the Consultative Committee for Space Data Systems(CCSDS)standard is proposed to meet the high throughput,low latency and high reliability requirement for high-speed satellite-to-ground data transmission systems of Low Earth Orbit(LEO).This design is parallel reconfigurable by inserting 0 into information bits and splitting cyclic matrices,and analyzed the structural characteristics of different parallelism encoding.Benefitting from the parallel reconfiguration,the throughput is increased and the flexibility is guaranteed.Furthermore,using optimized shift register adder accumulators can reduce the hardware resources.The proposed encoder design is implemented on Xilinx FPGA.The experimental results show that the maximum encoding speed is up to 1 Gbps@125 MHz,and the normalized throughput is increased by 17.1%compared with the similar parallel encoder.And resources of registers and look-up tables are reduced by 13.7%and 14.8%respectively,compared with the existing encoder.