Research On Call Admission Control Of High Delay Space Network Based On GEO Satellite

In recent years, with the accelerating of globalizing process, the economic and trade exchanges between countries are getting more and more, the demand of people for mobile communication systems is also getting higher and higher. Global maritime routes, military operations with high precision coverage requirements, and increasingly frequent natural disasters all throw a challenge to traditional terrestrial mobile communication systems. Due to the coverage span and weak survivability,traditional terrestrial mobile communication systems has been unable to meet the demands of contemporary people. The development of satellite mobile communication system is a good make up for the above shortcomings. With its greater coverage span and better survivability,satellite communication systems are playing an increasingly important role in civilian, disaster relief and military operations.In the GEO satellite mobile communication systems, because the GEO orbit height is relatively higher and static to the ground, although it brought sort of unique advantages as a communications system, but also a series of problems. The high orbit brought unavoidable delay, which is sometimes intolerable for voice services and so on, it is necessary to minimize the impact of the high delay. Although GEO satellites have a larger coverage area, a single satellite can theoretically cover one-third of the Earth, but due to the uneven distribution of users, it could generate the hot spot, which brought the load imbalance phenomenon between different GEO satellite beams. Therefore, it is meaningful to formulate a reasonable call admission control strategy. Through the frequency reuse technology, the user’s access request can be selected within a certain range, and the satellite resources can be maximized under the premise of ensuring the user’s demand via the cooperation between beams.In this paper, we first described the construction of satellite telecommunication systems and the related technology of call admission control of satellite telecommunication systems. Secondly, we analyzed the traditional access strategy in satellite communication systems, and selected the parameters to measure the performance of system according to the characteristics of the call admission control strategy. Finally,according to the GEO satellite communication scene, we established the corresponding system model, and set up several reasonable simulation parameters, to continue the simulation and analysis afterwards.In this paper, we focused on the phenomenorr of the nonuniformity of user distribution, the imbalance of load of diffent beams and the low rate of resource utilization of GEO satellite communication system, thus constructed the network model and proposed a channel occupation call admission control strategy based on the integrated weighting. By the adoption of the frequency reuse technology,the access requests of the users can select the best beam within a certain range, which is according to a reasonable algorithm, to improve the performance of the satellite communication system. Furthermore, we compared the different performance between the traditional. satellite ,call admission control and the strategy we proposed form several aspects,such as user’s transmission delay, system throughput, beam load variance and call blocking rate, and so on. Which demonstrate the advantages of the access control strategy we proposed upon the traditional ways and the aim of maximizing the resource utilization rate of GEO satellites is realized.