发明名称 |
Phase accumulation dual tone multiple frequency generator. |
摘要 |
<p>A method and apparatus for generating dual tome multiple frequency signals employing a low frequency quartz oscillator, wherein a phase accumulation dual tone multiple frequency generator is comprised of a low frequency quartz oscillator. Two phase selectors are connected to produce digital phase signals in response to a signal input. Two phase accumulators, each composed of an adder and a register, are connected to accumulate the phase signals. Two ROM based sine wave tables are addressed by the outputs of the accumulators. An adder adds the outputs of the ROMs, and a D/A converter produces an analog output from the output of the adder.</p> |
申请公布号 |
EP0391524(A2) |
申请公布日期 |
1990.10.10 |
申请号 |
EP19900301658 |
申请日期 |
1990.02.15 |
申请人 |
INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE |
发明人 |
CHEN, YARN-CHERN;CHUNG, CHERN-JSAIR |
分类号 |
H03B28/00;H04M1/50;H04Q1/45 |
主分类号 |
H03B28/00 |
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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