摘要:
复杂应用场景决定短距离无线通信系统面对多种干扰、较低硬件资源配置导致其抗干扰能力有限,为实现可靠传输,设计基于改进LDPC码的短距离跳频无线通信系统.其中,提出低复杂度校验和更新(LCU,low-complexity check sum updating)算法,降低计算复杂度;提出基于MTBF(multi-threshold bit flipping)的LCU-MTBF算法,提高译码性能,降低译码复杂度.仿真结果表明,LCU算法适用于多种硬判决译码算法,在不影响原有算法性能的基础上降低译码算法的计算复杂度;LCU-MTBF在误码率(bit error rate)为10?5、迭代次数为5时,获得0.15 dB性能增益,将MTBF算法中加法次数降低约40%;当误码率为10?4、信噪比为15 dB时,在部分频带干扰和全频带干扰下,基于改进LDPC码的短距离跳频无线通信系统均获得7 dB左右的性能增益,有效改善其干扰性能.%In short-range wireless communication system(SWCS),the complex scenarios make its transmission face the diverse interference,and lower hardware resource leads to its limited anti-interference capability.To achieve the reliable transmission,a frequency-hopping-based SWCS(FH-SWCS)with improved LDPC(I-LDPC)code was constructed.In FH-SWCS,a low-complexity check-sum updating(LCU)algorithm was proposed to reduce the amount of computation.LCU-based multi-threshold bit flipping(LCU-MTBF)algorithm was given to increase the reliability of bit-flipping,im-proving decoding performance and reduce the complexity of decoding.The simulation results demonstrate that LCU is suitable for multiple hard decisions decoding algorithm,and it can reduce the computational complexity of original de-coding algorithm without affecting its performance.When BER is 10?5,and iterations number is 5,0.15 dB performance gain can be achieved,and the number of additions algorithm can be reduced about 40%in LCU-MTBF.In FH-SWCS with I-LDPC,when BER is 10?4,and SNR is 15 dB,the performance gain about 7 dB can be achieved to improve the an-ti-interference of the system effectively.