S.M. Ho

Bio: S.M. Ho is an academic researcher. The author has contributed to research in topics: Personal Communications Service. The author has an hindex of 1, co-authored 1 publications receiving 148 citations.

On location management for personal communications networks

Abstract: Personal communications services (PCS) support mobile terminals (MTs) which are free to travel within the service coverage area. In order to effectively locate an MT when a called is initiated, location management schemes are used to keep track of the locations of the MTs. The current approach to location management requires each MT to report its location to the network periodically. The location information is then stored in databases. When a call is initiated. The network determines the current location of the called MT through a database lookup and paging procedure. A currently available standard for location management is described. Research results on location management are surveyed in detail.

Mobility management in next-generation wireless systems

Abstract: This paper describes current and proposed protocols for mobility management for public land mobile network (PLMN)-based networks, mobile Internet protocol (IP) wireless asynchronous transfer mode (ATM) and satellite networks. The integration of these networks will be discussed in the context of the next evolutionary step of wireless communication networks. First, a review is provided of location management algorithms for personal communication systems (PCS) implemented over a PLMN network. The latest protocol changes for location registration and handoff are investigated for mobile IP followed by a discussion of proposed protocols for wireless ATM and satellite networks. Finally, an outline of open problems to be addressed by the next generation of wireless network service is discussed.

Location management methods for third generation mobile systems

Abstract: This article provides an overview of the means and techniques used for subscriber location management in present cellular mobile networks. The overhead due to location management techniques used in the present cellular systems such as GSM, in particular in high traffic spots, has already been a source of concern and is expected to augment dramatically in future wireless systems. Several proposals have been made in the past addressing the problem associated with the cost of location management. The author provides an overview of these contributions; in particular, he classifies the techniques, mainly into non-memory-based and memory-based approaches. Subsequently, a simple evaluation of the current location updating procedure used in GSM is presented in the context of a PCS framework to illustrate the load placed on the radio channels and on the MSC/VLR processing.

Mobility management in current and future communications networks

Abstract: This article describes current and proposed protocols for mobility management for public land mobile networks (PLMNs), Mobile IP, wireless ATM, and satellite networks. The integration of these networks is discussed in the context of the next evolutionary step of wireless communications networks. First, a review is provided of location management algorithms for PCS implemented over a PLMN. The latest protocol changes for location registration and handoff are investigated for Mobile IP, followed by a discussion of proposed protocols for wireless ATM and satellite networks. Finally, an outline of open problems to be addressed by the next generation of wireless network service is discussed.

Location estimation and trajectory prediction for cellular networks with mobile base stations

Abstract: This paper provides mobility estimation and prediction for a variant of the GSM network that resembles an ad hoc wireless mobile network in which base stations and users are both mobile. We propose using a Robust Extended Kalman Filter (REKF) to derive an estimate of the mobile user's next mobile base station from the user's location, heading, and altitude, to improve connection reliability and bandwidth efficiency of the underlying system. Our analysis demonstrates that our algorithm can successfully track the mobile users with less system complexity, as it requires measurements from only one or two closest mobile base stations. Further, the technique is robust against system uncertainties caused by the inherent deterministic nature of the mobility model. Through simulation, we show the accuracy of our prediction algorithm and the simplicity of its implementation.

Dynamic hierarchical database architecture for location management in PCS networks

Abstract: This paper introduces a dynamic hierarchical database architecture for location management in personal communications service (PCS) networks. The proposed scheme allows the dynamic adjustments of user location information distribution based on the mobility and calling patterns of the mobile terminals (MTs). A unique distribution strategy is determined for each MT, and location pointers are set up at selected remote locations which indicate the current location of the MTs. This method effectively reduces the signaling and database access overhead for location registration and call delivery. Besides, the required processing is handled by a distributed network of directory registers and centralized coordination is not necessary. The functions of the other network elements, such as the home location register (HLR) and the visitor location registers (VLRs), remain primarily unchanged. This greatly facilitates the deployment of this scheme in current PCS networks.