Special Issue on Next Generation Wireless Technologies

The next generation wireless networks are expected to converge into a ubiquitous architecture, which includes high-speed cellular networks, wireless local area networks (WLANs), mobile ad hoc networks, peer-to-peer networks, wireless metropolitan area networks (WMANs), etc. The increasing demand of wireless multimedia services has motivated the development of broad wireless access in the heterogeneous wireless networks. Mobile subscribers can enjoy the high bit rate, low cost, ubiquitous coverage, and secure connection. For the next generation wireless networks, further extensive investigation, experimentation and development are necessary, such as capacity analysis/ enhancement, quality-of-service (QoS) support, power saving, wireless routing, security, and mobility management. This special issue presents recent cutting edge research and state-of-the-art technology. The accepted eight papers are selected from the 2nd International Conference on Broadband Networks (BroadNets’05, held in Boston, MA, Oct. 3–7, 2005), the 2nd International Conference on Quality of Service for Heterogeneous Wired/Wireless Networks (QShine’05, held in Orlando, FL, Aug. 22–24, 2005), and the 11th Mobile Computing Workshop (held in Taiwan, Mar. 31, 2005). These papers are timely and valuable for future analysis, implementation and experiments of heterogeneous broadband wireless networks. In the first paper “Dynamic power saving mechanism for 3G UMTS system,” Yang investigates a power saving mechanism for Universal Mobile Telecommunications System (UMTS). Analytic and simulation models are proposed to study the two control parameters: discontinuous reception (DRX) cycle and the inactivity timer threshold. Optimal values of the two parameters in terms of maximum power saving are obtained. A dynamic algorithm is also proposed to enhance the performance of DRX. In the second paper “Predictive dynamic channel allocation scheme for improving power saving and mobility in BWA networks,” Chen and Tan propose a signal-aware dynamic channel allocation (SDCA) to improve the channel utilization as well as to reduce the probability of out-ofservice for IEEE 802.16 networks. The SDCA not only increases the capacity of the system but saves the overall power consumption of the system well. A location prediction scheme is presented to prevent the out-of-service effect on mobile subscriber stations due to user mobility. In the third paper “Queue analysis and multiplexing of heavy-tailed traffic in wireless packet data networks,” Teymori and Zhuang investigate the queuing behavior of self-similar traffic flows for data applications in a packetswitching single-server wireless network. Close-form expressions are derived for the relation among the traffic parameters, the channel working state probability, the server capacity, and the queue distribution for an infinite Mobile Netw Appl (2007) 12:1–3 DOI 10.1007/s11036-006-0001-1