Leo Satellite Switching Control Strategy And Method Of Research

LEO (Low Earth Orbit) satellite communication is the development direction of the next generation satellite communication, which has obvious trait : large overlay area, less communication time delay and access at any time. This paper takes deep analysis and research on basic theory and methods of the LEO satellite handoff control technique, and brings forward the handoff control scheme which uses one special gateway to control the users handoff.The paper takes introduction about the classic composition of the satellite communication, then gives the general summary of the satellite communication characteristic,key technique,kinds of handoff and operate mode of the system. After the summary of the main characteristics on how the LEO satellite communication system control user handoff, a abroad handoff system control scheme is put forward.the scheme use the special gateway which is integrated in general gateway to control the all users'handoff through the intersatellite links. Then we take detailed introduction on system design about the function of the handoff system, including the special gateway,satellite handle,satellite voice transmission and the whole handoff control. A amended nearest distance handoff plan which is suit for the Walker constellation is put forward. At the same time we make some theory analysis on system, and the system performance is derived and forecasted in theory.After the system design is introduced, we use the Opnet software modeling the communication system, simulating the special gateway system control the users'communication and handoff through the intersatellite links. without confliction to the inland transparent transmission, we use the tunnel technique to solve the communication between the land network and the satellite network., and the detailed introduction is given on modeling the handoff control system.At last we set up a simulate scene for the abroard users communication, test and prove the correctness and the feasibility of the abroad handoff system. at the same time the superiority of the nearest distance plan on less calculating works,restrain the"pingpang"handoff,minish the handoff cost is also proved.