非成像阵列探测器外差系统性能分析  

Analysis on Performance of Heterodyne System with Non-imaging Array Detector

作　　者：董洪舟[1] 杨若夫[1] 杨春平[1] 敖明武[1] 

机构地区：[1]电子科技大学光电信息学院,四川成都610054

出　　处：《光学学报》2015年第12期38-43,共6页Acta Optica Sinica

基　　金：国家自然科学基金(61308109)

摘　　要：受视场角限制,由单点探测器构成的外差系统不能充分接收信号光功率。若用阵列探测器代替单点探测器进行探测,可以增大接收视场,从而增强接收的信号光功率。在考虑到热噪声、光电流饱和效应的前提下,对这种阵列探测系统的信噪比进行了分析。结果显示,相对于单点探测系统,阵列系统能较大幅度地提高信噪比。分析结果指出,由于叠加的热噪声存在,当阵列中单元数增加到一定数量后,信噪比不能得到进一步提高。还对非等相位叠加因素对系统性能的影响进行了分析。由于系统输出信号是各探测单元输出信号的叠加,实际应用中不可能实现完全的等相位叠加,通过数值计算,分析了该因素的影响,并指出它可以在硬件设计过程中得到有效控制。Limited by view field angle, heterodyne system composed of single point detector cannot receive signal beams power adequately. The heterodyne system in which the single point detector is replaced by array detector can enhance the received amount of signal power through enlarging view field angle. Taking into account the thermal noise and saturation effects, signal-noise ratio（SNR） of heterodyne system with array detector is researched. Results show that compared with single point detection system, it will gain a higher SNR. However, it is pointed out, when the number of the units in array increases to a certain number, SNR cannot attain more improvement because of the thermal noise. For the reason that the signal output of system is the sum of output of all detector units, it is impossible to realize equiphase superposition. Impact of superposition in non- equiphase on system is also investigated by calculation simulation, and results show that the impact can be controlled effectively in the hardware design.

关 键 词：探测器 阵列探测器 饱和效应 信噪比 非等相位叠加 

分 类 号：TN958[电子电信—信号与信息处理]