Domestic satellite technology, what is a black satellite laser communications technology – Sohu Mili pp点点通2006

What is the domestic satellite quantum black technology? A – inter satellite laser communication technology Sohu before the military channel, "Mo-tse" quantum satellite and the ground station communication test photos released, the red light and the green light appears to be science fiction docking. According to experts, this is actually the use of high-power laser to achieve the purpose of tracking – down light used to correct the angle of the telescope, the uplink light used to correct the angle of the laser. There are differences in the principle of the uplink and downlink spectrum, the current selection of red and green light is only to facilitate the project". So, in the free space quantum communication in the use of tracking technology in the end is how one thing, what are the mysteries? What is the APT Mo-tse quantum satellite and ground station has been able to achieve a more scientific communication test, its key technology lies in APT technology. In order to realize the reliable communication between satellite and satellite or satellite and ground station, the beam first requires a satellite can catch another satellite or ground station sent, called beacon, and the beam to the detector center, a process called capture body (Acqulisiton). Upon completion of the acquisition, the receiver is also required to issue a beam of light that requires the beam to point to a beacon of light, which is called Pointing. After receiving the light beam from the beacon light, the satellite also has to complete the acquisition process in order to make the two satellites or satellites and ground stations reach the communication connection state. In order to ensure that the two satellites or satellites and ground stations have been in a state of communication, we must always maintain this precise connection state, which is called the tracking port (Tracikllg). It is said that the above acquisition, pointing and tracking process for APT technology. Because the communication beam in optical communication is very narrow. Therefore, in order to ensure that the receiver can receive the signal energy is strong enough, must ensure that the communication error beam and the optical axis of the system to control the error within the range, APT technology is to ensure the requirement of the high precision. Therefore, APT plays an important role in inter satellite laser communication. The structure APT system of APT system can be divided into coarse aiming (coarse tracking) subsystem, fine aiming (fine tracking) subsystem and signal processing and control subsystem. Coarse aiming (coarse tracking) subsystem mainly completes the acquisition, pointing and tracking a large field of view, the coarse pointing system for a two axis turntable real optical servo, can drive the optical antenna for a large range of motion, but less bandwidth, tracking and positioning precision is low. The fine aiming system is used for the aim and precision tracking of the target. It is usually driven by a piezoelectric ceramic or a voice coil motor. So it is necessary to form a compound axis control system, which can be used for large range, high precision and fast positioning and tracking. The signal processing and control system is responsible for the control of the coarse and fine aiming (tracking) subsystem according to the feedback of the photoelectric encoder and the CCD sensor. A case study of SILEX system with mature technology. The structure of the SILEX system is shown in the following diagram, which is composed of a coarse aiming device, a fine aiming device, and an advanced aiming device.相关的主题文章: