Bipolar chaotic pulse position modulation communication system based on cyclic LDPC
Bipolar chaotic pulse position modulation communication system based on cyclic LDPC
复制标题
基于循环LDPC的双极混沌脉冲位置调制通信系统
DOI：
10.1186/1687-1499-2014-105
复制
发表时间：
2014-06-22
影响因子：
2.6
通讯作者：
Vafi, Sina
中科院分区：
文献类型：
--
作者：
Li, Hui;Liu, Hanyu;Vafi, Sina
为了克服混沌脉冲位置调制(CPPM)系统的误差传播，提高通信效率，提出了一种双极混沌脉冲位置调制(BCPPM)通信系统。在BCPPM中，每两位数据被设置为一组。第一比特和离散混沌映射确定发送脉冲的位置，第二比特确定发送脉冲的极性。信道中的每个脉冲都包含两个比特的信息，提高了通信效率。设计了一种(255,175)循环低密度奇偶校验码，并对其生成矩阵和奇偶校验矩阵进行了循环。此外，将所构造的BCPPM通信系统应用于循环LDPC中，以减小噪声的影响。发送端采用循环码的编码结构，接收端采用最小和算法进行译码。分析表明，该系统是安全的，对信道失真不敏感，便于多址通信。仿真结果表明，在加性高斯白噪声(AWGN)信道、多径信道、多用户模型和混合通信环境下，BCPPM系统比CPPM和混沌脉冲开关键控(CPOOK)系统具有更低的误码率。此外，由于采用了循环LDPC码，该系统更适合硬件实现。
To overcome the error propagation and improve the communication efficiency of the chaotic pulse position modulation (CPPM) system, the bipolar chaotic pulse position modulation (BCPPM) communication system is proposed here. In BCPPM, every two-bit data are set as a group. The first bit and the discrete chaotic map determine the position of sent pulse, while the second bit determines the polarity of sent pulse. Each pulse in the channel contains two-bit information, so this scheme improves the communication efficiency. A (255,175) cyclic low-density parity-check code (LDPC) was designed, and its generator matrix and parity check matrix are cycled. Furthermore, the constructed BCPPM communication system is utilized in the cyclic LDPC aiming to mitigate the effect of noise. In the transmitter, it uses the encoder structure of cyclic codes while the min-sum algorithm is deployed to decode in the receiver. The analysis indicates that the proposed system is secure, insensitive to the channel distortion and convenient for multiple access communication. The simulation results show that in the additive white Gaussian noise (AWGN) channel, multipath channel, multiuser model, and hybrid communication environment, the BCPPM system has lower bit error rate (BER) compared with those of the CPPM and chaotic pulse on-off-keying (CPOOK). In addition, using cyclic LDPC codes, the system is more suitable for hardware implementation.