Location management is a very critical and intricate problem in wireless mobile communication which involves tracking the movement of the mobile users in the cellular network. Particle Swarm Optimization (PSO) is proposed for the optimal design of the cellular network using reporting cell planning (RCP) strategy. In this state-of-the-art approach, the proposed algorithm reduces the involved total cost such as location update and paging cost for the location management issue. The same technique is proved to be a competitive approach to different existing test network problems showing the efficacy of the proposed method through simulation results. The result obtained is also validated for real network data obtained from BSNL, Odisha. Particle Swarm Optimization is used to find the optimal set of reporting cells in a given cellular network by minimizing the location management cost. This RCP technique applied to this cost minimization problem has given improved result as compared to the results obtained in the previous literature.
TopIntroduction
In a wireless mobile communication, location management is of prime importance as it is concerned with the tracking of the location of the mobile terminals so that the incoming call or data can be forwarded to the relevant cell within the cellular network. The number of mobile subscribers are rising exponentially and inorder to accommodate them within limited spectrum resources the cell capacity and coverage has to be increased which is achieved by decreased cell size according to the concept of frequency reuse (Mukherjee & De, 2016; Sidhu & Singh, 2007).Thus, the probability of movement of the mobile terminals from one cell to another increases within the network which increases the overhead cost for location management of the mobile subcribers. This paper aims to reduce the overhead cost incurred for tracking the exact location of the mobile users.
The wireless cellular network comprises of hexagonal shaped geographical areas called cells. The base station at the center of each cell services and monitors all the mobile devices within its coverage region. The base station is able to make the communication link between two active mobile terminals (MTs) through the mobile switching centre (MSC). The MSCs are connected to Public Switched Telephone Network (PSTN) as illustrated in Figure 1 which shows a typical cellular network.
In each cell, every mobile terminal (MT) communicates with another terminal through wireless links. The base stations are connected to a radio network controller (RNC) which plays an important role during the routing of a call in that service area. Forwarding a call to a MT is a complex operation. For the call delivery first the network need to locate the exact location of the cell where the MT resides. Thus, the location search of the cell where the MT is currently residing is an important and essential issue of mobile location management. Mobile location management is basically concerned with tracking an active MT within the wireless mobile network. As the MTs are free to move within the network area a certain amount of cost is associated with the network for locating them. The network resources management and development of strategies for reducing this network cost is called mobile location management (Anisetti et al., 2011; J & M, 2010). It mainly involves two fundamental operations i.e. location registration(update) and location search (paging). Location update is performed whenever a MT changes it cellular position, by automatically sending a location registration request signal to the MSC. Location update is necessary for keeping the record of the position of the MT within the mobile cellular network. Thus, the mobile location is updated to the current residing cell and after that all the call procedures are carried out by the present residing cell base station until the mobile moves to a new cell. When there is an incoming call to a mobile user, the MSC routes the call to the base station in which the mobile terminal is currently residing.The base station then sends a broadcast signal to all the mobile terminals within its coverage area and routes the call to that mobile terminal which responds to the broadcast signal.Thus, the call is established between the two MTs.This phenomenon is called paging where the signal is broadcast to the MTs within the range of the cellular base station (Al-Surmi, Othman, & Mohd Ali, 2012).
In this paper, BPSO is used to solve the location management issue.The paper is organized as follows: in section II problem formulation is elaborated.Section III explains particle swarm optimization technique for location management issue.Simulation results and analysis is discussed in section IV.Section V presents the conclusion and future scope.