Improvement of the capacity of the LEO mobile satellite systems using channel reshuffling

Abstract

This paper presents a reshuffling technique which should ensure a more optimal usage of the available resources in a interference limited low Earth orbit (LEO) mobile satellite systems (MSS). The scheme is based on optimization of the interference situation in the system. After each blocking (new call or handover) it is attempted to reshuffle the channels in a way that a free carrier which is more favorable in interference terms replaces a carrier whose usage leads to the congestion in that part of the system. Firstly, the reshuffling scheme has been combined with hybrid channel allocation (HCA), where for a certain part of the resources fixed cell allocation is applied while the rest was allocated dynamically (DCA) to every cell. Later on, only the DCA has been used. Both capacity and interference limited systems have been investigated. Simulation tests were carried out in order to evaluate the performance of these schemes. The results show that, in the interference limited LEO MSSs with non-uniform traffic the system performance parameters such as call blocking, handover failure and grade of service (GoS) are significantly better using reshuffling. However, it was proven that the reshuffling technique does not bring much improvement to the capacity limited systems.