Research On Radio Resource Management Technology In Systems Beyond 3G

Rapid progress of mobile communication and internet networks in recent years has seen a dramatically growing demand for wireless multimedia services requiring reliable and high-speed data transmission over a wireless channel. One of the most challenges for the future wireless communication systems (B3G, systems beyond 3G) is to support a large number of subscribers and to ensure the fulfillment of quality-of-service (QoS) requirements, given the limited availability of frequency spectrum.To solve this issue, many methods have been proposed, among which orthogonal frequency division multiple access (OFDMA) system is a promising candidate because of its ability to combat intersymbol interference (ISI) and flexibility for adaptive frequency channel control. Recently, adaptive radio resource management for multiuser OFDMA system has attracted enormous research interest, which can provide frequency domain diversity as well as multi-user diversity gain and improve effectively system performance.This dissertation focuses on radio resource management for adaptive OFDMA system, including adaptive radio resource allocation, downlink packet scheduling and call admission control. There are four major results in the dissertation.First, the ergodic capacity and optimal power allocation policy of broadband MIMO-OFDM systems in wireless fading channels are derived to determine the capacity limits of OFDM systems. Further, the sum-rate capacity and multiuser diversity gain of MIMO-OFDM system are shown from a multiuser information theory point of view. The results indicate that: the channel capacity of MIMO-OFDM system grows with the number of antennas and average received Signal Noise Ratio (SNR),...