论文部分内容阅读
随着无线通信技术的发展,超宽带(UWB)技术以其传统窄带通信所没有的优点,而得到了各界的关注。文中就多用户环境中脉冲位置调制(PPM)误符号率较高的问题,提出了一种新的超宽带的调制方式—脉冲位置宽度调制(PPWM)。该调制方式在原有的脉冲位置调制的基础上,加入了脉冲的宽度调制,用不同宽度的脉冲来传输不同用户的信息,使得在解调过程中能量匹配更加准确。给出了基于跳时(TH)的PPWM和PPM的信号模型,同时分析了TH-PP-WM和TH-PPM在多用户环境下的误符号率性能,以及TH-PPWM与用户数的关系。计算机仿真证明了TH-PPWM较TH-PPM能够更好的降低误符号率;同时在多用户的环境下,随着用户数的增加不会造成TH-PPWM误符号率性能的不稳定。
With the development of wireless communication technology, ultra-wideband (UWB) technology has drawn the attention of all circles for its advantages that traditional narrowband communication does not have. In this paper, we propose a new ultra-wideband modulation scheme called Pulse Position Width Modulation (PPWM), which is based on the problem of high symbol error rate in pulse position modulation (PPM) in multiuser environment. The modulation mode based on the original pulse position modulation, adding the pulse width modulation, with different width of the pulse to transmit different user information, making the energy matching in the demodulation process more accurate. The signal model of PPWM and PPM based on hopping time (TH) is given. The error symbol performance of TH-PP-WM and TH-PPM in multi-user environment and the relationship between TH-PPWM and number of users are also analyzed. Computer simulation proves that TH-PPWM can better reduce the symbol error rate than TH-PPM. Meanwhile, under the multi-user environment, the number of users will not cause TH-PPWM error rate error.