| 摘要 |
An output control unit of a mobile communication system includes a transmit up-converter board having first and second mixers responsive to first and second oscillation frequency signals, respectively, for up-converting the frequency of a transmission signal, an attenuator installed between the transmit up-converter board and a final output terminal for controlling output of the up-converted transmission signal order to eliminate unwanted signal characteristic irrespective of amplification and attenuation when the transmission signal is up-converted for transmission and a transceiver slave control unit responsive to the second oscillation frequency signal for generating a control signal for controlling the attenuator, wherein the transceiver slave control unit utilizes an interface unit controlled to produce phase locked loop control data for controlling a local oscillator to generate the second local oscillation frequency of a designated channel, wherein the local oscillator informs the interface unit that it is locked at the designated channel's frequency; a main processor unit for detecting that the local oscillator is tuned to the designated channel in response to an output from the interface unit indicating that the local oscillator is locked at the designated channel's frequency; a control memory for storing a control voltage conversion table of digital-to-analog conversion step values, wherein the main processor unit searches for an output attenuation value of the designated channel in a channel conversion table and accesses the control version conversion table to determine a digital-to-analog conversion step value corresponding to the output attenuation value of the designated channel; and a digital-to-analog converter for converting the digital-to-analog conversion step value transmitted from the main processor unit into the control signal for controlling the attenuator.
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