摘要
猫眼逆向调制激光通信由于通信速率高,回波信号微弱,对接收放大电路提出了低噪声、高增益和宽带宽的严格要求。首先分析了猫眼逆向调制激光通信链路模型和信噪比对误码率的影响。然后,根据系统设计指标分析了电路的带宽、增益和噪声限度等性能参数;在此基础上设计了由跨阻放大模块和增益可变主放大模块构成的接收放大电路。最后,计算了电路的总噪声,并对电路的响应特性进行了仿真。该接收放大电路的带宽达到140 MHz,信号增益大于70 dB,总噪声电流约为1.34×10^(-7)A。结果表明,该设计能满足系统后续的数据处理要求。
Because of high communication speed and weak echo signals, cat's eye modulating retroreflecting laser communication has strict requirements of low noise, high gain and wide bandwidth for receiving amplifier circuits. Firstly, the influence of link models for cat's eye modulating retro-reflecting laser communication and Signal-to-Noise Ratio (SNR) on Bit Error Rate (BER) is analyzed. Then, the parameters such as circuit bandwidth, gain and noise limit are analyzed according to the performance specifications of the system. On this basis, a receiving amplifier circuit consisting of a transimpedance preamplifier module and a main amplifier module with adjustable gain is designed. Finally, its total noise is calculated and its response characteristics are simulated. It has the bandwidth of 140 MHz, the signal gain greater than 70 dB and the total noise current about 1.34 × 10-7A. The result shows that the design of the circuit can meet the requirement of following data processing of the system.
出处
《红外》
CAS
2014年第9期31-36,共6页
Infrared
关键词
激光通信
猫眼效应
光电调制器
接收电路
误码率
laser communication
cat's eye
photoelectric modulator
receiving circuit
bit error rate