弱湍流下Turbo码编码数字脉冲间隔调制差错性能分析

Analysis of Error Performance for Turbo Coded Digital Pulse Interval Modulation under Weak Turbulence

数字脉冲间隔调制（DPIM）的符号长度变化不固定，因而分析该调制方式在Turbo码编码下的差错性能存在困难。在建立分析模型和推导差错率的基础上，在弱湍流信道条件下仿真分析了Turbo码编码前后的系统差错性能，同时与高斯信道条件下的系统差错性能进行了比较。仿真分析结果表明，弱湍流信道条件下的系统差错性能不如高斯信道条件下的系统差错性能，但在两种信道条件下，引入Turbo码编码技术均可获得3～6dB的编码增益，能够有效改善系统的差错性能，具有良好的军事应用价值。

The symbol length of digital pulse interval modulation （DPIM） is variable, so there are some difficulties to analyze error performances of Turbo coded DPIM. After the analytic model is set up and the error rate is derived, the system error performances of uncoded and Turbo coded DPIM are simulated and analyzed under weak turbulence channel, and the system error performances under Gaussian channel are simulated for comparison. The results show that error performances under weak turbulence channel are inferior to those under Gaussian channel, but for the two channels, introduction of Turbo code can get the code gain of 3-6 dB, which improves the error performance of system effectively and has applied value for military communications.