Sougata Chakraborty

A New Method for Fast and Low Cost Handover in Leo Satellites

Now-a-days LEO satellites have an important role in global communication system. They have some advantages over GEO & MEO satellites such as power requirement and endto-end delay is lower and it has more efficient frequency spectrum utilization between satellites and spotbeams. So in future they can be used as a replacement of modern terrestrial wireless networks. But they main problem of LEO satellites is that they have large relative speed than the speed of mobile nodes (MN) & earth. That’s why the handover occurrence is more. So the call blocking probability (Pb) and force call termination probability (Pf) is also higher. To overcome this problem several handover techniques is proposed. Here we propose Billboard Manager based handover (BMBHO) technique using the concept of Billboard Manager (BM) proposed by Aysegul et al in 2006 but in a different way. Here we reduce the scanning time significantly. Also the cost is reduced. Here we also describe how to reduce (Pf). In this paper you will find a set of simulations both for our proposed method & standard handover methods. We can find that this method is very useful by the simulation results.

A New Method for Controlling Mobility Management Cost of PatHO-LEO Satellite and Mobile IP Network

In low earth orbit(LEO) satellite network Mobility management is one of the key technologies. The aim of mobility management is to track where the subscribers are, allowing calls, SMS and other mobile phone services to be delivered to them. In this paper, we have proposed an idea of controlling the frequency hops and hence controlled the mobility management cost of patHO-LEO and Mobile IP network. General Terms Satellite and Mobile IP Network

Area based Mobility Management by using GPS in LEO Satellite Networks

Though Low Earth Orbit (LEO) satellites have some distinct characteristics such as low propagation delay, low power requirements and more efficient spectrum allocation due to frequency reuse between satellite and spotbeams but the higher relative speed than terrestrial mobile networks decreases the quality of service as a result of a huge number of handovers. To overcome this problem a number of handover management schemes have been proposed out of which Mobile IP (MIP) is the standard one. But its mobility management cost is too high. Here we have proposed a low cost area based mobility management method (ABMM) using GPS and Paging for LEO satellite networks, which use GPS to decrease Paging cost and location update cost. Through mathematical analysis simulation results shows that this method is better than the standard mobility management methods.

A Time based Mobility Management Method for Leo Satellite Networks

Low Earth Orbit (LEO) satellite networks will work as an important role in future global communications as it can provide wireless connectivity to any part of the world. It has some distinct characteristics such as low propagation delay, low power requirements and more efficient spectrum allocation due to frequency reuse between satellite and spotbeams. But the higher relative speed than terrestrial mobile networks is the main disadvantage of LEO satellites. As a result, the frequency of handover is more which decreases the quality of service. To overcome this problem, many solutions are given by scientists. Here we have proposed a Time Based Mobility Management (TBMM) method in which we have divided the total 24 hours into two phrases: active phrase and idle phrase and apply precise location management and loose location management simultaneously. Through mathematical analysis simulation results shows that this method is better than the standard mobility management methods.

Location Manager based Handover Method for LEO Satellite Networks

Low Earth Orbit (LEO) satellite made a great impact to the scientists towards the end of the previous decade because of its some interesting features such as low propagation delay, low power requirements and the ability to communicate with handheld terminals. That’s why future satellite networks are now conceived as complementary rather than competitive to terrestrial networks. But as the speed of LEO satellite is higher than Mobile Nodes (MN) and earth’s speed, the no of handover occurrence is more which degrades the overall communication quality. Also the call blocking probability and forced call termination probability is more. To solve these problems, a number of handover methods have been proposed by different scientists. Here we have proposed a fast method for handover named Location Manager Based Handover method for LEO satellite networks where we have use Location Manager (LM) for reducing the scanning time. LM is used to store all the mobility pattern of all the satellites. To know how this method works, we run a set of simulations for handover latency, handover throughput and call blocking probability for our proposed method with the standard methods. Results show that this algorithm can significantly improve the overall communication performance.

A New Channel Borrowing Database Algorithm in Multimedia LEO Satellite Communications

LEO satellite networks are going to play an indispensable role in the development of ubiquitous broadband multimedia systems because of their some attracting characteristics such as low power dissipation, low propagation delay and more efficient spectrum allocation due to frequency reuse between satellites and spotbeams. So they are considered to be the replacement of terrestrial wireless networks. But as the speed of LEO satellites is high relative to the terrestrial mobile networks which moves at lower speed but at more random directions. As a result the number of handover occurrence is very frequent in LEO networks. To overcome these problems a suitable bandwidth allocation strategy along with connection admission control technique must have to be followed. Scientists have proposed many strategies but none can fulfil all the requirements. Here we have proposed a new channel borrowing database algorithm for the channel borrowing strategy. Simulation results shows that our proposed method has less call dropping probability and a better fairness index.

Algorithm based Approach for the Connection Establishment in the Fast Handover in Leo Satellites in BMBHO

Now-a-days LEO satellites have an important role in global communication system. They have some advantages like low power requirement and low end-to-end delay, more efficient frequency spectrum utilization between satellites and spot beams over GEO and MEO. So in future they can be used as a replacement of modern terrestrial wireless networks. But the handover occurrence is more due to the speed of the LEOs. Different protocol has been proposed for a successful handover among which BMBHO is more efficient. But it had a problem during the selection of the mobile node during handover. Here we have proposed an algorithm so that the connection can be established easily with the appropriate satellite. By simulation we have shown that it will reduce the handoff latency as well as efficiency of the

An Optimum Cost Handover Algorithm for LEO Satellites

Low Earth Orbit (LEO) satellite networks are foreseen to complement terrestrial networks in future communication. LEO satellites have important advantages such that low endto-end delay and power requirement and more efficient frequency spectrum allocation due to frequency reuse between satellite and spot beams. But the speed of LEO satellites is much higher than mobile nodes. As a result the handover occurrence is more. Handover may degrade system performance depending upon techniques employed by the satellite systems. So an appropriate handover scheme must be devised to increase system performance. This paper introduces a new handover algorithm which optimizes between the cost of handover and quality of service (QOS) parameters. Also it decreases handover delay. Simulations indicates that this algorithm is better than current algorithms in shorten transmission delay and minimizing handover cost.

Introduction of Handover Manager for Better Handover Latency and Handover Throughput during Leo Satellite Handover

LEO satellite has an important role in global communication system. They have advantages like low power requirement and lower end-to-end delay, efficient frequency spectrum utilization between satellites and spotbeams over MEO and GEO satellites. So in future they can be used as a replacement of modern terrestrial wireless networks. There are a lot of handover techniques for LEO satellites like seamless handover (SeaHO-LEO) ,PatHO-LEO .In our proposed work we have suggested a new handover technique for SeaHOLEO by introducing a Handover Manager (HM) during the handover process and by simulation we have also shown that it a better approach by comparing it with other existing handover techniques as it reduces the handover latency, propagation delay, call blocking probability more than any other technique.