发明名称 |
INDUCTORLESS ACTIVE FILTER PHASE SHIFT DEMODULATOR |
摘要 |
An inductorless quadrature demodulator for frequency modulated signals is disclosed. A limited FM signal is passed through an active filter (26) and a phase shift network (30) to produce a quadrature signal. The limited FM signal is compared with the quadrature signal in an EXCLUSIVE OR gate (24) and then low pass filtered (36) to obtain recovered audio. The active filter (26) includes a transconductance amplifier (60) whose center frequency can be adjusted by appropriate adjustment of the amplifier's bias current. The bias current is temperature compensated to allow operation of the demodulator over a wide temperature range. |
申请公布号 |
CA1282843(C) |
申请公布日期 |
1991.04.09 |
申请号 |
CA19850491095 |
申请日期 |
1985.09.19 |
申请人 |
MOTOROLA, INC. |
发明人 |
DAVIS, WALTER L.;PRIETO, YOLANDA |
分类号 |
H03D3/06;H03D3/02;H03D3/20 |
主分类号 |
H03D3/06 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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