摘要:
Provided are a macro-diversity transmission apparatus and method for providing a broadcast/multicast service using multiple transmitting antennas in a wireless cellular communication system. The apparatus and method apply spatial multiplexing using multiple antennas within a cell and obtain additional diversity among adjacent cells or base stations. Therefore, the signal-to-interference ratio (SIR) and diversity order of signals received by terminals at cell boundaries can be increased. Consequently, cell coverage for a particular data rate can be increased, and transmission power can be reduced. Here, additional diversity applied among cells or base stations includes a method of changing antennas transmitting the same information among cells and a cyclic delay diversity (CDD) method.
摘要:
Disclosed is a downlink signal configuring method and device, and synchronization and cell search method and device using the same in a mobile communication system. A downlink frame has plural symbols into which pilot subcarriers are distributively arranged with respect to time and frequency axes. Initial symbol synchronization and initial frequency synchronization are estimated by using a position at which autocorrelation of a cyclic prefix of a downlink signal and a valid symbol of the downlink is maximized, and cell search and integer-times frequency synchronization are estimated by using pilot subcarriers included in the estimated symbol. Fine symbol synchronization, fine frequency synchronization, and downlink frame synchronization is estimated by using an estimated cell search result. Downlink frequency and time tracking is performed, cell tracking is performed by using a position set of pilot subcarriers inserted into the downlink frame, fine symbol synchronization tracking and fine frequency synchronization tracking are repeated by using the pilot subcarriers to perform the frequency and time tracking of the downlink frame.