| 摘要 |
<p>A transmitter is provided in a base station which communicates with a mobile station of a high-speed communication user and a mobile station of a low-speed communication user according to a spread spectrum system. The transmitter includes a first antenna having a wide directivity, a second antenna having a directivity narrower than that of the first antenna, a first transmission unit for transmitting a first transmission signal from the first and second antennas to the mobile station of the low-speed communication user, and a second transmission unit for transmitting a second transmission signal from the second antenna to the mobile station of the high-speed communication user. In addition, a receiver provided in the mobile station of the low-speed communication user includes a receiving unit for receiving the first transmission signals sent from the first and second antennas of the base station, a first demodulator for despreading the received first transmission signal using a despreading code, a delay element for delaying the despreading code by the predetermined period of time, and a second demodulator for despreading the received first transmission signal using the delayed despreading code.</p> |
