Channel Estimation

Although 3rd generation mobile radio systems have not yet become widely operational, research concerning beyond 3G mobile radio systems has already started around the globe. At the Research Group for Radio Communications the system architecture with the acronym JOINT (Joint Detection and Transmission Integrated Network) is developed. JOINT is a contribution to the project “Joint Research Beyond 3G” (JRB3G) sponsored by the SIEMENS Company, Germany, in which German and Chinese universities are involved. JOINT is a service area (SA) based concept. Each service area consists of access points (APs) receiving/transmitting radio signals from/to the mobile terminals (MTs) active in the SA. Each SA is equipped with a central unit (CU), which is responsible for signal processing. Joint Detection (JD) is applied for uplink data detection and Joint Transmission (JT) is used for downlink data transmission. Both techniques rely on the knowledge of the mobile radio channel, which is gained by the technique termed Joint Channel Estimation (JCE). JCE is a pilot-aided channel estimation technique. The active MTs transmit known symbols - termed pilots – to the APs, and based on these symbols and on the corresponding received signals, estimates of all radio channels between each MT and AP are obtained at the CU. Exploiting the potential and evaluating the performance of JCE in JOINT is the task of this work.