Telecommunications – Use or access blocking
Patent
1979-03-26
1981-12-08
Birmiel, Howard A.
Telecommunications
Use or access blocking
178 2217, 179 15R, 375 21, 375112, H04K 100
Patent
active
043051529
ABSTRACT:
A security communication system comprises a transmission apparatus including a scrambling circuit for scrambling an information signal according to a specific code and a reception apparatus including a deciphering circuit for deciphering an output signal of the transmission apparatus according to substantially the same code as the specific code. The transmission apparatus further includes a first signal generating circuit for supplying a synchronizing signal to the scrambling circuit to drive the same, a signal synthesizing circuit having a first input terminal coupled to the output terminal of the first signal generating circuit, and a switching circuit connected between the output terminal of the scrambling circuit and a second input terminal of the signal synthesizing circuit, said switching circuit being opened while the first signal generating circuit is generating a synchronizing signal. The reception apparatus further includes a second signal generating circuit and a synchronization circuit for supplying a drive signal to the deciphering circuit when the synchronizing signal component in the output signal of the transmission apparatus synchronizes with the output signal of the second signal generating circuit.
REFERENCES:
patent: 2950348 (1960-08-01), Mayer et al.
patent: 3124652 (1964-03-01), Biagi et al.
patent: 3723878 (1973-03-01), Miller
patent: 4052565 (1977-10-01), Baxter et al.
patent: 4079195 (1978-03-01), Frutiger
patent: 4086537 (1978-04-01), Asakawa et al.
patent: 4099027 (1978-07-01), Whitten
patent: 4100374 (1978-07-01), Jayant et al.
patent: 4179586 (1979-12-01), Mathews, Jr. et al.
"An Experimental Phase Code Modulation System for Short-Haul", Davis, Bell System Tech. Journ. vol XLI, 162, pp. 1-3.
Asakawa Shigeru
Nakamura Makoto
Okai Tsukasa
Sugiyama Fumio
Birmiel Howard A.
Tokyo Shibaura Denki Kabushiki Kaisha
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