Bit error rate analysis of OOK modulation scheme under non-coherent demodulation for space uplink optical communication systems

With the development of communication technique, space microwave communication technique has shown its limitation in the transmission of high data rate. While space optical communication system introduces laser as the signal carrier and can solve this problem very well. At present, on-off keying (OOK) is one of the most important modulation scheme widely used in space optical communication systems, and the intensity modulation direct detection (IM-DD) non-coherent demodulation is the corresponding demodulation scheme. However, researchers always pay attention to the coherent demodulation for OOK modulation scheme. That deviates from the practical systems. This paper focuses on the OOK communication systems with non-coherent demodulation and analyzes the relationship between BER and the key parameters of this systems, such as transmission power, ratio of beam radius and transmission power, ratio of receiver radius and transmission power, ratio of divergence angle and transmission power, and so on. We also compare the BER performance between non-coherent demodulation and coherent demodulation under the same low level of noise. The work will practically benefit the optimal design of the space optical communication systems.