随着GNSS(全球导航卫星系统)的发展,需要在一个频段上发射多路导航信号,以提高频谱利用率.多路信号的线性叠加其包络是非恒定的,在通过高功率放大器时会产生AM/PM失真,从而引入定位误差.为了使多路复用后的信号保持包络的恒定,伽利略和GPS系统分别提出了互复用和CASM恒包络处理方法,并已经应用在其试验卫星上.对互复用技术进行了分析研究,得出了信号功率效率与功率分配之间的关系,并给出了功率效率最大化的功率配置方式和功率效率的下限.研究对GNSS中多路信号复用的恒包络处理有重要的指导意义.%With the development of Global Navigation Satellite System, it's necessary to send multi-channel navigation signals in one frequency to improve the spectrum utilization rate. The envelope of signal linearly overlapped multi-channel signals is not constant, and this signal will be distorted by AM/PM when it passed through a high power amplifier, thus bringing in position error. In order to keep the envelope of signal combined by multi-channel signals constant, in Galileo system and GPS system, Interplex and CASM constant envelope combined methodologies have been adopted separately, and these methodologies have been applied to their test-satellite. Interplex will be studied in this paper, and the relationship between useful signal power efficiency and power allocation for each channel is obtained. Based on the above study, the optimum configuration with maximum the power efficiency, and the lower limit value of power efficiency are obtained. The study of this paper has an important guiding significance for constant envelope combined methodologies in GNSS.
展开▼
