l GPS/GLONASS组合技术的优势
由于GPS和GLONASS这两种星基导航系统在系统设计、导航定位机理、工作频段、调制方式、信号和星历数据结构等方面是基本相同和近似的,都以发射扩频测距码、测量卫星与用户之间的伪距来完成导航定位,所以就...l GPS/GLONASS组合技术的优势
由于GPS和GLONASS这两种星基导航系统在系统设计、导航定位机理、工作频段、调制方式、信号和星历数据结构等方面是基本相同和近似的,都以发射扩频测距码、测量卫星与用户之间的伪距来完成导航定位,所以就存在利用一部用户设备同时接收这两种卫星信号的可能性.在两个系统各自单独工作时,可能存在难于覆盖的空白带,且会受制于人.但是,如果能将两个系统组合使用,由于可用卫星数目增多,不仅能填补单一系统存在的覆盖空白问题,而且可使系统精度显著提高.因此,GPS/GLONASS组合技术已经成为近几年研究的重点.展开更多
This paper presents a new Transmitted Reference (TR) Ultra-WideBand (UWB) receiver based on Spatial Diversity (SD), which employs Multi-Antenna Technology (MAT) to improve the performance of TR-UWB receiver. According...This paper presents a new Transmitted Reference (TR) Ultra-WideBand (UWB) receiver based on Spatial Diversity (SD), which employs Multi-Antenna Technology (MAT) to improve the performance of TR-UWB receiver. According to the amplitude of correlator output of every antenna branch, this paper analyzed the performances of the proposed TR-UWB receiver employing three different kinds of combination strategies, i.e., Maximum Ratio Combination (MRC), Equal Gain Combination (EGC), and Selective Combination (SC), which are different from conventional ones, and theoretically proved that the performance of EGC is better than MRC. Simulation results verify that when EGC is adopted and BER=10-3, increasing three antennas provides Signal to Noise Ratio (SNR) gain of about 3 dB in CM4 channel and SNR gain of about 2 dB in CM2 channel.展开更多
文摘This paper presents a new Transmitted Reference (TR) Ultra-WideBand (UWB) receiver based on Spatial Diversity (SD), which employs Multi-Antenna Technology (MAT) to improve the performance of TR-UWB receiver. According to the amplitude of correlator output of every antenna branch, this paper analyzed the performances of the proposed TR-UWB receiver employing three different kinds of combination strategies, i.e., Maximum Ratio Combination (MRC), Equal Gain Combination (EGC), and Selective Combination (SC), which are different from conventional ones, and theoretically proved that the performance of EGC is better than MRC. Simulation results verify that when EGC is adopted and BER=10-3, increasing three antennas provides Signal to Noise Ratio (SNR) gain of about 3 dB in CM4 channel and SNR gain of about 2 dB in CM2 channel.