发明名称 Radio selective call receiver capable of adjusting radio signal level
摘要 <p>In a radio selective call receiver for lowering a radio signal level in accordance with the state where reception of a sync signal is enabled/disabled, an amplifier 53 amplifies a radio signal fed from a base station. A frequency converter 54 shifts a frequency of the radio signal amplified in the amplifier 53 to a first frequency band and a second frequency band. A demodulator 55 converts a radio signal shifted to the second frequency band by the frequency converter 54 into a base band signal. A level detector 56 outputs a direct current voltage relative to an electric field intensity level of the radio signal shifted to the second frequency band by the frequency converter 54. A comparator 57 compares the direct current voltage output from the level detector 56 with a predetermined voltage. A controller 42 judges whether a first sync signal can be received by a base band signal demodulated by the demodulator 55, and outputs a control signal "L" to an attenuation circuit 52 when determined that reception of the first sync signal is impossible. The attenuating circuit 52 lowers the level of the radio signal by the control signal "L" output from the controller 42. &lt;IMAGE&gt;</p>
申请公布号 EP0792015(A2) 申请公布日期 1997.08.27
申请号 EP19970103029 申请日期 1997.02.25
申请人 NEC CORPORATION 发明人 KUDOH, KAZUHIRO
分类号 H04J3/06;H03G3/30;H04B1/10;H04L7/08;H04Q7/14;(IPC1-7):H03G3/20;H04B1/26 主分类号 H04J3/06
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