The key technique of optical wireless communication is Acquisition, Pointing and Tracking (APT). Owing to very large distance of optical wireless communication, all these factors such as equipment joggling, the scintillation will cause drift of facula. Traditional solution consists of acquisition system and tracking and pointing system. The acquisition system means that the acquisition of target in large scope of range of response. The tracking and pointing system means that accurate pointing to the communicative target. The function of system is to accurately point the target and to real-time track it after the acquisition of the target. This paper presents an innovative solution. The main idea proposed in this paper is to take the diameter of the light beam emitted by the optical taper in control, using the piezoelectric ceramic to adjust the smaller diameter of the optical taper of polymer optical fiber. This can make the facula larger when the system proceed to acquire and track, and make it smaller when the system proceed to communicate. The larger the facula is, the lower the energy density and SNR become. However, because of the lower precision requirement of information in tracking than in communication, the technique can fulfill the request generally. Meanwhile, the adopting of the OCDMA technique can greatly reduce the power request of the laser equipment. This new technique combines the communication system and the beacon system together, resulting in the smart decrease in the equipment price and the sharp simplification in the system scale.