Yung-Chun Lin

WiMAX Location Update for Vehicle Applications

In IEEE 802.16e mobile Worldwide Interoperability for Microwave Access (WiMAX), paging groups (PGs; groups of base stations) are used to identify the locations of mobile stations (MSs). An anchor paging controller (APC) is assigned to an MS to handle location tracking for the MS. During location update, the WiMAX network may or may not relocate the APC. This paper considers a linear WiMAX base station layout for vehicle applications, where a base station serves as a roadside unit, and a WiMAX MS installed in a vehicle serves as an onboard unit. In these vehicle applications, APC relocation may significantly affect the network traffic. This paper proposes an analytic model to study the performance of the location update with/without APC relocation. Our study provides guidelines to utilize the APC relocation for vehicles with various moving behaviors.

Performance of Mobile Telecommunications Network With Overlapping Location Area Configuration

In a mobile telecommunications network, the location area (LA) of a mobile station (MS) is tracked by an LA update (LAU) mechanism. To reduce the LAU traffic caused by the ping-pong effect, the overlapping LA concept is introduced. In the overlapping LA configuration, an LA selection policy is required to select the new LA at an LAU when the MS enters a new cell covered by multiple LAs. This paper describes four LA selection policies and proposes an analytic model to study the performance of these LA selection policies. Our study provides guidelines to determine an appropriate degree of overlapping among the LAs.

Repacking on demand for speed-sensitive channel assignment

In mobile telecommunications networks, radio channels are limited resources that should be carefully allocated. To increase network capacity, channel assignment can be exercised in a hierarchical cellular network (HCN). By considering the speeds of MSs, we propose an HCN channel assignment approach called repacking on demand (RoD). A simulation model is developed to investigate the performance of RoD and some previously proposed approaches for HCN. Our study quantitatively shows that RoD significantly outperforms the previous proposed approaches.

Channel assignment for hierarchical cellular networks

In mobile telecommunications operation, radio channels are scarce resources and should be carefully assigned. One possibility is to deploy the hierarchical cellular network (HCN). We study a HCN channel assignment scheme called repacking on demand (RoD). RoD was originally proposed for wireless local loop networks. We expend this work to accommodate mobile HCN. A simulation model is proposed to study the performance of HCN with RoD and some previously proposed schemes. Our study quantitatively indicates that RoD may significantly outperform the previous proposed schemes

A Multi-link Mechanism for Heterogeneous Radio Networks

Nowadays, smart mobile devices drive the mobile traffic growth rapidly. Most smart mobile devices are equipped with multiple radio network interfaces, such as High Speed Packet Access (HSPA), Long Term Evolution (LTE), and Wi-Fi. Therefore, integration of multiple networks is a viable solution to fulfill traffic offloading and the Quality-of-Service (QoS) requirement of data usage for mobile users. In this paper, we propose a multi-link mechanism to handle the radio network selection and switching between LTE and Wi-Fi networks. A Multi-Link Adaptor (MLA) and a Multi-Connection Manager (MCM) are proposed for the User Equipment (UE) and the core network, respectively, to handle the multi-link mechanism. The applications executed in the UEs do not need to be modified under the proposed approach. The MLA maintains a QoS class table and a routing table for the network selection procedure and uses the GPRS Tunneling Protocol-Control plane (GTP-C) control messages to execute network switching. In the future, we will measure the throughput of the multi-link network and the switch delay between the heterogeneous radio networks.

Repacking on demand for hierarchical cellular networks

In mobile telecommunications operation, radio channels are scarce resources and should be carefully assigned. One possibility is to deploy the hierarchical cellular network (HCN). This paper studies a HCN channel assignment scheme called repacking on demand (RoD). RoD was originally proposed for wireless local loop networks. We expend this work to accommodate mobile HCN. A simulation model is proposed to study the performance of HCN with RoD and some previously proposed schemes. Our study quantitatively indicates that RoD may significantly outperform the previous proposed schemes.

An OSA application server for mobile services

Purpose – Open service access (OSA) is a flexible and efficient approach for mobile service deployment. In OSA, network functionality offered to application servers (ASs) is defined by a set of service capability features (SCFs). The AS implements services by accessing the service capability through the standardized OSA application programming interface.Design/methodology/approach – The paper shows how the AS provides services by integrating the services supported by the SCFs. Then it uses the OSA mutual authentication and the push to talk over cellular service to illustrate the interaction among the AS modules and how the AS interacts with the framework and the SCFs.Findings – With this environment, the service developers are not required to access the details of the underlying mobile network, and thus the service deployment can be sped up. The purpose of this paper is to propose an AS architecture.Originality/value – This paper proposed an OSA AS architecture. Based on this architecture, a new applicati...

The Universal Local IP Access for Small Cells

Today, more than 50% of voice calls and 60% of the wireless traffic data originate in the indoor environment, and to improve the indoor radio coverage and transmission quality becomes a major issue. The deployment of the Small Cells (SCs) could easily and efficiently increase the indoor radio access quality and capacity. The SCs also provide the universal Local IP Access (uLIPA) feature allowing outside UEs connect to and access their home Local IP Access (LIPA) networks from the visited SCs. This paper proposed four schemes to support the uLIPA service. We compared their performance with the well-known prior solution, Virtual Private Network (VPN). Our study indicates that except the IPAM approach, the other uLIPA schemes bring significant overhead for those services with small-sized IP packets, e.g., the popular G.729 VoIP service. This study quantitatively shows that for both radio and wire transmission, the IPAM outperforms the other approaches.