摘要
在跟踪和数据中继卫星系统反向链路中,多路频分复用信号通过高功率放大器时存在严重的交调干扰,导致输出的各路阵元信号严重失真.针对这一问题,该文通过幂级数模型分析高功率放大器调幅-调幅(AM-AM)变换对通道间幅度一致性的影响机理,建立幅度不一致性对波达方向(direction of arrival,DOA)估计影响的数学模型,并进行计算机仿真.理论分析和仿真结果表明:高功率放大器的AM-AM变换不会引起估计角度的偏移,但会导致空间角度范围内的谱峰值降低,同时使3 dB谱宽变宽.此外,AM-AM变换还会导致DOA估计性能恶化.
In the reverse link of tracking and data relay satellite system(TDRSS),AM-AM conversion in the high-power amplifier for frequency-division multiplexing(FDM) signals causes severe inter-modulation interference to the signals in different channels.The interference results in distortion of the channel signals.The present work uses power series to analyze the influence of AM-AM conversion on the amplifier's magnitude consistency among the channels,and establish a mathematical model of the influence of magnitude inconsistency on DOA estimation.Theoretical analysis and simulation results show that AM-AM conversion in high-power amplifier does not affect the offset of the estimated angle,but reduces the spectral peak within the spatial angle and increases the 3 dB bandwidth.AM-AM conversion also deteriorates the DOA estimation performance.
出处
《应用科学学报》
EI
CAS
CSCD
北大核心
2010年第5期470-475,共6页
Journal of Applied Sciences
基金
国家自然科学基金(No.61001089)
重庆市自然科学基金(No.2010BB2049)资助
关键词
跟踪和数据中继卫星系统
波达方向
AM-AM变换
高功率放大器
幅度不一致性
tracking and data relay satellite system(TDRSS)
direction of arrival(DOA)
AM-AM conversion
high-power amplifier
magnitude inconsistency