Patent ID: 8630268
Filing Date: 2014-01-14
Classification: H04B

Abstract:
1. A distributed antenna system comprising: a base station apparatus comprising a plurality of antenna ports; a terminal having a plurality of terminal antennas; a plurality of remote radio units dispersed spatially so as to accommodate one or more distributed antennas; and an antenna switch configured to switch a connection between the one or more distributed antennas and the plurality of antenna ports in the base station apparatus, wherein the base station apparatus is configured to collect a terminal throughput for uplink and downlink communications, a number of simultaneous communication terminals, and radio propagation channel information from each of the one or more distributed antennas to each of the plurality of terminal antennas; wherein each of the one or more distributed antennas is configured to receive one of a pilot signal or a control signal from the terminal; wherein the base station apparatus is configured to select an antenna cluster comprising a first group consisting of a predetermined number of the one or more distributed antennas in descending order of a first received power of the one of the pilot signal or the control signal, or wherein the base station is configured to identify and store antenna cluster information identifying a second group consisting of a predetermined number of the one or more distributed antennas in descending order of a second received power of the one of the pilot signal or the control signal, by transmitting or receiving, substantially prior to the selection of the antenna cluster, the one of the pilot signal or the control signal between the distributed antennas, and wherein the base station apparatus is configured to select a current antenna cluster by determining the antenna cluster that contains a distributed antenna with the highest received first power of the one of the pilot signal or the control signal, by utilizing the antenna cluster information, or by selecting the antenna cluster that contains the distributed antenna that is used in a current communication mode; and wherein the base station apparatus is configured to communicate in one of a plurality of communication modes that are different in communication speed or throughput, and to select one of the plurality of communication modes based on whether only one terminal participates in the communication or a plurality of terminals participate in the communication simultaneously, and wherein one or more antennas of the selected antenna cluster and the selected terminal antennas are allocated to a transmitting/receiving antenna; wherein the base station apparatus is configured to judge the switching of the communication mode by, when the terminal throughput of the uplink or downlink communication is greater than the sum of the request value and a certain threshold value or when the number of simultaneous connection terminals is less than a preset threshold, computing a second estimated throughput in the one or more other communication modes and selecting the second communication mode for which the second estimated throughput satisfies the request value and the communication speed or the throughput of the second communication mode is lower than the communication speed or the throughput of the first communication mode; wherein computing the estimated throughput comprises: allocating one or more antennas of the selected antenna cluster and of the terminal antennas as one or more transmitting/receiving antennas and allocating the antenna ports of the base station apparatus corresponding to the one or more transmitting/receiving antennas; creating, by the base station apparatus, an antenna connection pattern representing the correspondence between the predetermined number of the one or more distributed antennas and the plurality of antenna ports in the selected second communication mode and the selected predetermined number of the distributed antennas; notifying, by the base station apparatus, the antenna switch of the antenna connection pattern; receiving, by the antenna switch, the antenna connection pattern from the base station apparatus; and switching, by the antenna switch, the correspondence between the predetermined number of distributed antennas and the plurality of antenna ports in accordance with the designated antenna connection pattern; and switching the communication mode between the base station apparatus and the terminal in order to continue the communication.