发明名称 |
TRANSFERRING DIGITAL INFORMATION IN A TELEPHONE SYSTEM |
摘要 |
In a telephone system for digitalized speech transmission additional digital information is transferred without disturbing a speech communication (a) in progress. At the sending side, time slots for the transmission of the additional digital information are created by momentarily suppressing the digital speech signals transmitted on a digital channel and, at the receiving side, the digital information is extracted from the time slots and replaced by digital signals (m) which constitute a continuous amplitude function starting from the amplitude value which was transmitted immediately before the time slot. To distinguish the additional digital information from speech signals a special identifying code is added at the sending side. The speech transmission may employ either Delta Modulation or Pulse Code Modulation. |
申请公布号 |
AU4277978(A) |
申请公布日期 |
1979.06.28 |
申请号 |
AU19780042779 |
申请日期 |
1978.12.21 |
申请人 |
ERICSSON, TELEFONAKTIEBOLAGET L M |
发明人 |
KARL FOLKE LENNART NYBERG;KJELL STURE JOSEFSSON |
分类号 |
H04J3/00;H04J3/12;H04M11/06;H04Q11/04 |
主分类号 |
H04J3/00 |
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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