A method for selecting a diversity mode to be applied by a transmitter having two cross-polarized antenna arrays, each representing a diversity branch, comprising the steps of: providing a plurality of diversity mode performance chart look-up tables, mapping a respective individual diversity mode to a respective pair of time correlation value and space correlation value for the two cross-polarized antenna array beams, wherein a respective individual diversity mode is presented by a mapping area, wherein the plurality of performance chart look-up tables is parameterized by an indication of a ratio of received powers from the diversity branches, first selecting one of the performance chart look-up tables dependent on determined ratio of received powers from separate beams, and second selecting one of the individual diversity modes according to the mapping to the determined actual time relation and space correlation values from the first selected performance chart look-up table.
An apparatus and method for demodulating signals transmitted from one or more Node-Bs using transmit diversity methods determined on a Node-B basis in a mobile communication system based on code division multiple access (CDMA). In the apparatus, a plurality of fingers assigned on a path-by-path basis discriminates among multipath signals received from the one or more Node-Bs. A combiner selectively combines signals output from the fingers according to the use of transmit diversity. A transmit diversity signal processor demodulates the signals combined by the combiner on the basis of one transmit diversity method determined by a transmit diversity controller. The transmit diversity controller determines the transmit diversity method through transmit diversity information received from the Node-Bs, and controls the transmit diversity signal processor according to the determined transmit diversity method.
An apparatus and method for Transmit Diversity mode transition in a mobile communication system for use with transmit diversity is disclosed. In a mobile communication system including a Node B comprising one or more antennas and a Mobile Station (MS) for transmitting Transmit Diversity information to the Node B to enable the plurality of antennas to implement the maximum Transmit Diversity. The apparatus and method for assigning weights to transmission data of the antennas to enable the Node B to implement the maximum Transmit Diversity when the mode transition occurs in the Transmit Diversity modes comprise determining whether the mode transition occurs using the Transmit Diversity information; and assigning a weight generated considering the relationship between a current weight and a previous weight used before the mode transition time to the data transmitted over the antennas if it is determined that the mode transition occurs.
