CAJ | 학술논문

针对水声信道复杂多变、强多途和大起伏干扰等特点，提出采用码率兼容QC-LDPC码的自适应信道编码技术，以提高水声数据传输的可靠性和水声信道的信道吞吐率。建立了码率兼容QC-LDPC码在水声信道中的仿真模型，构造码率为1/2、2/3…5/6等一系列QC-LDPC码，在三种典型的水声信道中对其性能进行仿真。结果表明所设计的码率兼容QC-LDPC码在三种不同信道下可行有效，能较大地提高水声通信系统的性能。由于信道时延越长、信噪比越低，满足通信指标的码率就越低；并给出码率兼容QC-LDPC码在浅海水声信道中不同信噪比下满足通信性能指标的编码码率的查找表。码率兼容QC-LDPC码提高了水声通信的信道利用率，具有灵活的编译码性能，在水声自适应通信中具有很好的应用前景。
침대수성신도복잡다변、강다도화대기복간우등특점，제출채용마솔겸용QC-LDPC마적자괄응신도편마기술，이제고수성수거전수적가고성화수성신도적신도탄토솔。건립료마솔겸용QC-LDPC마재수성신도중적방진모형，구조마솔위1/2、2/3…5/6등일계렬QC-LDPC마，재삼충전형적수성신도중대기성능진행방진。결과표명소설계적마솔겸용QC-LDPC마재삼충불동신도하가행유효，능교대지제고수성통신계통적성능。유우신도시연월장、신조비월저，만족통신지표적마솔취월저；병급출마솔겸용QC-LDPC마재천해수성신도중불동신조비하만족통신성능지표적편마마솔적사조표。마솔겸용QC-LDPC마제고료수성통신적신도이용솔，구유령활적편역마성능，재수성자괄응통신중구유흔호적응용전경。
The underwater acoustic (UWA) channel is characterized as a complex variable, strong multipath and fluc-tuation interference channel. Adaptive channel coding techniques which use rate-compatible QC-LDPC (RC QC-LDPC) codes are proposed to enhance the reliability of UWA data transmission and channel throughput. A system simulation model including RC QC-LDPC codes for the UWA channels is built. With constructing a series code-rates (such as 1/2, 2/3,…, 5/6) of QC-LDPC codes, the performance of the system is simulated over three different kinds of UWA channels. The simulation results show that the designed RC QC-LDPC codes are feasible and effective, can dramatically improve the performance of UWA communication system, have good applicability in UWA channels. In the case that the worse the channel, due to longer channel delay and lower signal-to-noise ratio, the lower the code-rate is taken to meet system communication indicators. The lookup table (LUT) of the rate compatible QC-LDPC codes, which meet the communication indicators of the shallow water acoustic communication system under different sig-nal-to-noise ratios, is given. The RC QC-LDPC codes with flexible encoding and decoding performances can improve the utilization of UWA communication channel and have good application prospects.