Multi-hop Virtual Cellular Network

1. Introduction The 3rd generation mobile communication systems, known as IMT-2000 systems, have data transmission capability of up to 2 Mbps [1]. Recently, high-speed downlink packet access (HSDPA) aiming at a maximum peak throughput of around 10 Mbps is under development for the enhancement of the IMT-2000 systems [2]. However, since information transferred over the Internet is becoming increasingly rich, even wireless transmission capability of the enhanced IMT-2000 will sooner or later become insufficient. There is a strong demand for peak rates of around 100Mbps ~ 1Gbps even in mobile communications systems to offer mobile users Internet-related broadband multimedia services. This is the task of the so called 4th generation (4G) mobile communications systems, which is expected to emerge around 2010 [3]. However, there will be an important problem to overcome; as the transmission rate becomes higher, the peak transmit power of a mobile terminal (MT) should be increased. Reducing the cell size is a simple way to avoid larger peak transmit powers while increasing the transmission rate [3], [4]. However, if the cell size becomes smaller, the control signal traffic for handover and location registration may increase. To avoid this problem, we recently proposed a wireless multi-hop virtual cellular network (VCN) [5], [6]. This article introduces the wireless multi-hop VCN. After presenting the VCN concept in Sect.2, Sect. 3 describes the multi-hop route construction algorithm and the multi-hop channel allocation using channel segregation dynamic channel allocation (CS-DCA) algorithm. The transmit power efficiency and the blocking probability are discussed in Sect.4.