为了比较各种类脉冲位置调制性能,对类脉冲位置调制的编码结构、平均发射功率、带宽需求、传信率、功率谱密度、信道容量等进行了比较,分析了其性能特点及使用场合.结果表明,开关键控调制方式容易实现,但功率利用率低;脉冲位置调制方式提高了功率利用率,但是带宽效率差,同时需要符号同步;数字脉冲间隔调制结构复杂,缩短了符号长度,带宽效率高,不需要符号同步;双头脉冲间隔调制方式提高了带宽效率和传输容量,不需要符号同步,大大简化系统实现复杂度.%In order to compare the performance of various types of pulse position modulation, the coding structure, average transmitted power, bandwidth requirements, transmission rate, power spectral density and channel capacity were compared. Their characteristics and application fields were analyzed. The results show that, on off keying is easy to implement, but power utilization ratio is too low; pulse position modulation improves power utilization ratio but bandwidth availability ratio is low and it need symbol synchronization; digital pulse interval modulation shortens the length of the symbols, it has high bandwidth availability ratio and does not need symbol synchronization, but it is too complex; dual header pulse interval modulation improves the bandwidth efficiency and transmission capacity and do not need symbol synchronization, greatly simplify the complexity of the system implementation.
展开▼
