| 摘要 |
An improvement to a spread-spectrum code-division-multiple-access system, using a channel sounding signal from a base station (BS) (12) to provide initial transmitter power levels for remote stations (RS) (11). The base station (12) transmits BS-spread-spectrum signals at a first frequency and receives RS-spread-spectrum signals at a second frequency. The RS-spread-spectrum signals are transmitted by the remote stations (11) at the second frequency. The BS-spread-spectrum signals at the first frequency are outside the correlation bandwidth of the RS-spread-spectrum signals at the second frequency. The base station (12) transmit a BS-channel-sounding signal at the same carrier frequency being used by the remote stations (11) to transmit a spread-spectrum signal to the base station (12). The bandwidth of the BS-channel-sounding signal is not much of the bandwidth of the BS-spread-spectrum signal. Each of the remote stations (11) receives the BS-channel-sounding signal at the second frequency. Each remote station (11) includes an RS demodulator (35) for tracking the BS-channel-sounding signal and outputting an RS-receiver signal, and an RS-power-level circuit (36). In response to the RS-receiver signal, the RS-power level circuit (36) adjusts the initial RS-power level. The base station (12) has an interference canceller (51). The interference canceller (51) reduces the BS-channel-sounding signal, transmitted from the base station (12).
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