Composition and Characteristics of VSAT Satellite Communication System
Ⅰ. What is the VSAT satellite communication system?
VSAT is the abbreviation of Very Small Aperture Terminal, so it is also called satellite small data station (small station) or personal earth station (PES). The "small" here refer to the small antenna diameter of the small station equipment in the VSAT satellite communication system, usually 1.2-2.4M.
The use of this system for communication has the characteristics of strong flexibility, high reliability, convenient use, and the small station can be directly installed on the user side. The VSAT user data terminal can be directly connected to the computer to complete data transmission, file exchange, image transmission and other communications. tasks, thereby getting rid of the problem of ground interruption stations for long-distance communication. Using VSAT as a dedicated long-distance communication system is a good choice.
Ⅱ. The composition of the VSAT satellite communication system
The VSAT satellite communication system consists of two parts: space and ground.
The space part of the VSAT satellite communication system is the satellite. Generally, the geostationary orbit communication satellite is used. The satellite can work in different frequency bands, such as C, ku and Ka frequency bands. The transmit power of the on-board transponder should be as large as possible to make the antenna size of the VSAT ground terminal as small as possible.
The ground part of the VSAT satellite communication system consists of a central station, a remote station and a network control unit. The function of the central station is to collect data from satellites and then distribute the data to each remote station. The remote station is the main body of the satellite communication network. The VSAT satellite communication network is composed of many remote stations. The more these stations, the lower the cost of each station. Generally, the remote station is directly installed at the user's place and connected with the user's terminal equipment.
Ⅲ. Characteristics of VSAT satellite communication system
VSAT satellite communication system has very obvious characteristics, it mainly includes the following aspects.
1. The diameter of the ground (remote) station antenna is small, generally less than 2 meters, and currently 1.2 to 1.8 meters are used more. Mountaineers sometimes use portable personal earth stations with a diameter of 0.3 meters.
2. The transmit power is small, generally between 1 and 3 watts.
3. The weight is very light. The commonly used ones are dozens of kilograms, and some are as small as several kilograms, which are easy to carry.
4. Low price, economical and practical. Not only the price of the equipment is low, but also the economic benefits it achieves are far greater than the price of the equipment.
5. The construction period is short. It is much simpler than the traditional means of terrestrial communication, and does not need to erect cables or optical cables. It's also not like microwave communication has to set up a relay station every 50 kilometers. In the VSAT satellite communication system, as long as the necessary equipment is installed at both ends of the communication, and the installation of this equipment is relatively simple.
6. The cost of communication has nothing to do with the distance of communication. In a general communication system, the longer the distance, the higher the cost, while the VSAT satellite communication has nothing to do with the distance, and the longer the distance, the more suitable it is to use VSAT communication.
7. VSAT satellite communication is not affected by terrain and climatic environment, because it does not need to erect ground facilities, and the interference from the ground is small.
8. The biggest advantage of VSAT satellite communication technology is the flexible networking, easy expansion and use, and convenient maintenance, because it does not have complex ground equipment.