BASE STATION IN CODE DIVISION MULTIPLE ACCESS SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a small-sized and inexpensive base station that accurately detects a phase difference between received signals corresponding respectively to each of a plurality of omnidirectional antenna elements. SOLUTION: A base station 105 is provided with a plurality of antenna elements 107-1-107-n each receiving a transmission signal subjected to spread modulation corresponding to each of a plurality of mobile stations. A frequency shift section 111 applies frequency shift to a received signal corresponding to each of a plurality of the antenna elements 107-1-107-n. A synthesis section 115 synthesizes received signals that are frequency-shifted to generate a synthesis signal. A reception section 119 applies inverse frequency conversion to the synthesis signal to convert the signal into a digital signal. A signal processing section 123 applies spread demodulation processing to the digital signal corresponding to each of a plurality of the antenna elements 107-1-107-n to specify a radio wave incoming direction of each of a plurality of mobile stations 101-1'-101-n'.