CODE DIVISION MULTIPLE ACCESS WIRELESS SYSTEM WITH CLOSED LOOP MODE USING 90-DEGREE PHASE ROTATION AND BEAM FORMER CONFIRMATION

摘要

PROBLEM TO BE SOLVED: To provide a system that uses a comparatively simple algorithm to decode a signal with high accuracy in response to a Doppler fading velocity when transmission antenna diversity is employed for the CDMA system. SOLUTION: A user station 12 of the wireless communication system 10 is provided with an inverse spread circuit 22 that receives slots sent from at least two transmission antennas of a transform station 14 to spread the slots inversely. The slots include 1st and 2nd channel including different pilot symbols, respectively. The user station 14 is provided with a circuit 50 that measures the values of the 1st and 2nd channels for each prescribed slot from the respective 1st and 2nd transmission channels. Furthermore, the user station 14 is provided with a circuit 52 that measures a phase difference for each prescribed slot in response to the 1st and 2nd channel measured values and in response to the rotation of a prescribed slot by 90 degrees with respect to the slot received by the inverse spread circuit 22 just before the prescribed slot.