Adaptive optics systems need beacons to detect wave- front information.Different modes of bea-cons and wave- front detecting have a great influence on the performance criterion such as the system band-width and stability.Researching the performance of the system is full of critical meaning to properly design and evaluate a system.Based on the system work flow,the light wave characteristics of beacons,the methods of exposure,read-out of wave-front sensors,and the transfer function models of adaptive systems are built using mechanism analysis methods.The calculation equations of system bandwidth and phase margin are de-rived.The effects of sample frequency and controller parameter on system performance are studied.Results show that different modes of beacons and wave-front detecting can cause different system time delays,which alter the system bandwidth and stability.