发明名称 |
Integrated data voice multiplexer supporting handshake and loop-back protocols |
摘要 |
An integrated data voice multiplexer (IDVM) capable of simultaneously supporting loop-back and communication handshake protocols with no performance degradation. This allows the IDVM to be used in both point-to-point and packet switch networks. The IDVM is of the type using frequency shift keyed FSK modulation of two or more carriers to send a data signal. The presence or absence of carrier signals indicates loop-back state. Narrowband modulation is selectively added to at least one carrier to support handshake protocol. The preferred narrowband modulation is biphase at a rate lower than the FSK modulation rate. Encoder, decoder, data hold and detect circuits for supporting standard RS232 protocol are disclosed.
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申请公布号 |
US4908819(A) |
申请公布日期 |
1990.03.13 |
申请号 |
US19880293531 |
申请日期 |
1988.12.23 |
申请人 |
SEISCOR TECHNOLOGIES, INC. |
发明人 |
CASADY, DONALD R.;TEODORESCU, IOAN V. |
分类号 |
H04M11/06 |
主分类号 |
H04M11/06 |
代理机构 |
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主权项 |
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地址 |
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