JPS5588451A - Privacy telephone system - Google Patents
Privacy telephone systemInfo
- Publication number
- JPS5588451A JPS5588451A JP16573278A JP16573278A JPS5588451A JP S5588451 A JPS5588451 A JP S5588451A JP 16573278 A JP16573278 A JP 16573278A JP 16573278 A JP16573278 A JP 16573278A JP S5588451 A JPS5588451 A JP S5588451A
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- code
- privacy telephone
- synchronous signal
- input
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
- H04K1/00—Secret communication
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
Abstract
PURPOSE:To secure the synchronization for the reception circuit and also increase the communication quality by securing the automatic transmission for the privacy telephone code in the form of the synchronous signal for the silence period. CONSTITUTION:The transmission input signal applied to input terminal 11 is delivered through amplifier circuit 12, A/D converter circuit 13 and exclusive logic sum circuit 17 each. The privacy telephone code for disturbance of transmission signals is supplied to the other input of circuit 17 from privacy telephone code generator circuit 15 and in synchronization with the synchronous signal given from bit synchronous signal oscillator circuit 14. The code array is decided by the signals sent from code control circuit 16 for the privacy telephone code. The reception input signal applied to input terminal 21 is supplied to bit synchronous detector circuit 22 to produce the bit synchronous signal synchronized with circuit 14 in the transmission circuit and then to change the signal into the synchronous signal for D/A converter 25, privacy telephone code generator circuit 23 and code synchronous detector circuit 27 each. The reception input is supplied also to circuit 27, thus the synchronous signal of the privacy telephone code is detected.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP16573278A JPS5588451A (en) | 1978-12-26 | 1978-12-26 | Privacy telephone system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP16573278A JPS5588451A (en) | 1978-12-26 | 1978-12-26 | Privacy telephone system |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5588451A true JPS5588451A (en) | 1980-07-04 |
Family
ID=15818013
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP16573278A Pending JPS5588451A (en) | 1978-12-26 | 1978-12-26 | Privacy telephone system |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5588451A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5732134A (en) * | 1980-08-05 | 1982-02-20 | Mitsubishi Electric Corp | Fm communication equipment for communication orientation |
US8156630B2 (en) | 2006-04-06 | 2012-04-17 | Showa Denko K.K. | Method of joining members |
-
1978
- 1978-12-26 JP JP16573278A patent/JPS5588451A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5732134A (en) * | 1980-08-05 | 1982-02-20 | Mitsubishi Electric Corp | Fm communication equipment for communication orientation |
US8156630B2 (en) | 2006-04-06 | 2012-04-17 | Showa Denko K.K. | Method of joining members |
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