US4217469A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coding and decoding apparatus for the protection of communication secrecy
Assignee: Individual
•
Filing: 1978-03-10
•
Granted: 1980-08-12
•
Expires: 1998-03-10
Abstract
Abstract Apparatus for coding and decoding of electrical signals within a pre-established frequency band and useful for providing communication secrecy. A transmission and coding circuit and a reception and decoding circuit is provided between means for the generation and reception of electrical signals and means for the exchange of coded signals with at least one other coding and decoding apparatus. Commutation means is utilized for complementarily enabling the circuits. The circuits include first means for temporarily storing consecutively received portions of the electrical signals, second means for enabling the operation of the first means to consecutively store in memory the signal portion and to transmit those signal portions in a different order, and third means for controlling the storage of the electrical signal portions in memory within the first means according to one of a fixed sampling frequency and two or more frequencies variable in a prestablished order.
Inventors
- 👤 Emilio Martelli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:30
CPC Classifications
H; H04; H04K; H04K1/00; H04K1/06
Claims Analysis
Total Claims: 45
Claim 1
Independent Claim
268 words
Apparatus for the coding and decoding of electrical signals within a pre-established frequency band and useful for providing communication secrecy, which may be connected between means for the generation and reception of said electrical signals and means for the exchange of said coded signals with at least one other coding and decoding apparatus, comprising a transmission and coding circuit and a reception and decoding circuit for said signals, commutation means for complementarily enabling said transmission and coding circuit and said reception and decoding circuit, said circuits comprising first means for temporarily storing consecutively received portions of said electrical signals, and second means for enabling the operation of said first means to consecutively store in memory said signal portions and to transmit said signal portions, in a different order, to one of said exchange means and said means for the reception of said signals, in which said first means includes a plurality of memory elements (22'-25', 23-26) in which said second means comprises means (123) for generating logic signal whose states correspond each to one of the memory elements (23-26) of said first means and which evolve according to an established sequence, a first group of counter circuits (101, 102, 103) each one associated with one of said memory elements, processing circuit means (130) in said coding and decoding circuits and responsive to signals from said logic signal generating means (123) for enabling said counter circuits to transmit numerical information contained in said counter circuits to a first group of connections (201, 202, 203) and thereafter to establish the numerical information in said counter circuits at a pre-established value.
Claim 2
Dependent Claim
268 words
Apparatus for the coding and decoding of electrical signals within a pre-established frequency band and useful for providing communication secrecy, which may be connected between means for the generation and reception of said electrical signals and means for the exchange of said coded signals with at least one other coding and decoding apparatus, comprising a transmission and coding circuit and a reception and decoding circuit for said signals, commutation means for complementarily enabling said transmission and coding circuit and said reception and decoding circuit, said circuits comprising first means for temporarily storing consecutively received portions of said electrical signals, and second means for enabling the operation of said first means to consecutively store in memory said signal portions and to transmit said signal portions, in a different order, to one of said exchange means and said means for the reception of said signals, in which said first means includes a plurality of memory elements (22'-25', 23-26) in which said second means comprises means (123) for generating logic signal whose states correspond each to one of the memory elements (23-26) of said first means and which evolve according to an established sequence, a first group of counter circuits (101, 102, 103) each one associated with one of said memory elements, processing circuit means (130) in said coding and decoding circuits and responsive to signals from said logic signal generating means (123) for enabling said counter circuits to transmit numerical information contained in said counter circuits to a first group of connections (201, 202, 203) and thereafter to establish the numerical information in said counter circuits at a pre-established value.
Claim 3
Dependent Claim
79 words
Apparatus according to claim 1 in which said logic signal generating means (123) controls said processing circuit means (130) to enable, in said coding circuits, the operation of said memory elements associated with said counter circuits, said processing circuit means receiving at a second input thereof a signal from an output of each counter circuit and generating output signals which establish particular values of numerical information in said counter circuits notwithstanding the state of said logic signal generating means.
Claim 4
Dependent Claim
82 words
Apparatus according to claim 1, including a second group of counter circuits (106, 107, 108) and a sequence control circuit (109) all of which receive positioning input signals from said first group of connections (201, 202, 203), said control circuit (109) determining a forced advancing of one step of the sequence of said logic signal generating means (123) correspondingly with coincident values of said numerical information transmitted in two consecutive instants corresponding to the consecutive enabling of two of said memory elements.
Claim 5
Dependent Claim
35 words
Apparatus according to claim 3, in which each of said second group of counter circuits (106, 107, 108) includes an output for enabling in said reception circuit the operation of said memory element associated therewith.
Claim 6
Dependent Claim
32 words
Apparatus according to claim 1, including memory means (125) coupled to said logic signal generating means (123) for controlling an initial state of the sequence established by said logic signal generating means.
Claim 7
Dependent Claim
18 words
Apparatus according to claim 5, in which said memory means (125) is controlled by a programming keyboard means.
Claim 8
Dependent Claim
69 words
Apparatus according to claim 5, including a positioning control circuit (100) for advancing the sequence of said logic signal generating means (123) a finite number of steps from its first initial state to a second initial state, and to allow afterward, in a plurality of steps immediately consecutive to said second initial state, a positioning at a pre-established initial value of said first and second groups of counter circuits.
Claim 9
Dependent Claim
16 words
Apparatus according to claim 5, in which said memory means is controlled by punched card means.
Claim 10
Dependent Claim
16 words
Apparatus according to claim 5, in which said memory means is controlled by magnetic card means.
Claim 11
Dependent Claim
16 words
Apparatus according to claim 5, in which said memory means is controlled by sealed selector means.
Claim 12
Dependent Claim
38 words
Apparatus according to claim 1, in which said transmission and reception circuits are provided with a plurality of time base generators (79, 53) for controlling the advancing of the signal sequence of said logic signal generating means (123).
Claim 13
Dependent Claim
182 words
Apparatus for the coding and decoding of electrical signals within a pre-established frequency band and useful for providing communication secrecy, which may be connected between means for the generation and reception of said electrical signals and means for the exchange of said coded signals with at least one other coding and decoding apparatus, comprising a transmission and coding circuit and a reception and decoding circuit for said signals, commutation means for complementarily enabling said transmission and coding circuit and said reception and decoding circuit, said circuits comprising first means for temporarily storing consecutively received portions of said electrical signals, and second means for enabling the operation of said first means to consecutively store in memory said signal portions and to transmit said signal portions, in a different order, to one of said exchange means and said means for the reception of said signals, including third means for controlling the storage of said electrical signal portions in memory within said first means with a sampling frequency selectable between one of a fixed frequency and two or more frequencies variable in a pre-established order.
Claim 14
Dependent Claim
182 words
Apparatus for the coding and decoding of electrical signals within a pre-established frequency band and useful for providing communication secrecy, which may be connected between means for the generation and reception of said electrical signals and means for the exchange of said coded signals with at least one other coding and decoding apparatus, comprising a transmission and coding circuit and a reception and decoding circuit for said signals, commutation means for complementarily enabling said transmission and coding circuit and said reception and decoding circuit, said circuits comprising first means for temporarily storing consecutively received portions of said electrical signals, and second means for enabling the operation of said first means to consecutively store in memory said signal portions and to transmit said signal portions, in a different order, to one of said exchange means and said means for the reception of said signals, including third means for controlling the storage of said electrical signal portions in memory within said first means with a sampling frequency selectable between one of a fixed frequency and two or more frequencies variable in a pre-established order.
Claim 15
Dependent Claim
25 words
Apparatus according to claim 12, in which said commutation means comprises analog gates (4', 36' and 5, 19) for channeling signals for transmission or reception.
Claim 16
Dependent Claim
18 words
Apparatus according to claim 12, in which said first means includes a plurality of memory elements (22'-25', 23-26).
Claim 17
Dependent Claim
36 words
Apparatus according to claim 14, in which said memory elements are of the digital type, and further including an analog-to-digital converter (21') and a digital-to-analog converter (33'), respectively located upstream and downstream of said memory elements.
Claim 18
Dependent Claim
15 words
Apparatus according to claim 14, in which said memory elements are of the analog type.
Claim 19
Dependent Claim
62 words
Apparatus according to claim 14, in which said second means comprises a logic memory (65') within which a plurality of states are stored, which correspond each to one of said memory elements (22', 23', 24', 25') and which evolve according to a coding sequence in said transmission and coding circuit and according to a decoding sequence in said reception and decoding circuit.
Claim 20
Dependent Claim
34 words
Apparatus according to claim 17, in which said coding and decoding sequences are cyclically repeated through control of a clock signal and are enabled in a complementary mode through a manual control element (56').
Claim 21
Dependent Claim
18 words
Apparatus according to claim 18, in which said commutation means is actuated through said manual control element (56').
Claim 22
Dependent Claim
25 words
Apparatus according to claim 18, and including selection means (70') which may be actuated exteriorly for establishing said cyclic sequences and an initial starting state.
Claim 23
Dependent Claim
15 words
Apparatus according to claim 20, in which said selection means (70') comprises sealed selector means.
Claim 24
Dependent Claim
14 words
Apparatus according to claim 20, in which said selection means comprises punched card means.
Claim 25
Dependent Claim
14 words
Apparatus according to claim 20, in which said selection means comprises magnetic card means.
Claim 26
Dependent Claim
68 words
Apparatus according to claim 17, including decoding means (30') for decoding the output signals of said logic memory (65'), said decoding means receiving a signal from a manually controlled element (76') for controlling the use of a predetermined one (22') of said memory elements, said predetermined memory element (22') allowing transmission of said electrical signal portions according to the same order in which said signal portions were received.
Claim 27
Dependent Claim
46 words
Apparatus according to claim 12, including synchronization signal means for the transmission and the reception in a continuous mode of synchronization signals, said synchronization signal means comprising a generating circuit and a detecting circuit for said synchronization signals, whose operation is enabled in a complementary mode.
Claim 28
Dependent Claim
35 words
Apparatus according to claim 25, in which said generating circuit for said synchronization signals comprises a sinusoidal signal synthesizer (97') in which the phase of the sinusoidal signal generated therein is periodically inverted through 180°.
Claim 29
Dependent Claim
80 words
Apparatus according to claim 26, in which said synthesizer is formed by a digital-to-analog converter and said phase inversion is obtained by controlling said synthesizer by a clock logic signal from an output of a logic gate (93') of the EX-OR type, said logic gate receiving a clock signal at a first input thereof and a logic signal, alternately at level "0" or "1" with a period equal to the period of said phase inversion, at a second input thereof.
Claim 30
Dependent Claim
33 words
Apparatus according to claim 25, in which said first means includes a plurality of memory elements (22', 23', 24', 25'), and further including a band-eliminating filter (11') located upstream of said memory elements.
Claim 31
Dependent Claim
26 words
Apparatus according to claim 28, in which said filter (11') attenuates said synchronizing signals and electrical signals whose frequency is near that of said synchronizing signals.
Claim 32
Dependent Claim
64 words
Apparatus according to claim 23, in which said filter (11') is of the type comprising a plurality of capacitors having a first armature connected to the input of said filter and a second armature cyclically connected to the output of said filter through an electronic commutator; said filter being further provided with a control input (14') to allow an inversion of said cyclic connection.
Claim 33
Dependent Claim
37 words
Apparatus according to claim 30, including an analog switch (20'), with a logic control, located at the output of said filter (11') and actuated during the reception phase and coincidentally with said inversion of said cyclic connection.
Claim 34
Dependent Claim
41 words
Apparatus according to claim 12, in which said third means includes a chain of dividers (72) for dividing the frequency of an oscillating signal according to a ratio which is one of fixed frequency and variable between at least two values.
Claim 35
Dependent Claim
41 words
Apparatus according to claim 12, including fourth means for the transmission and the reception of synchronizing signals, said fourth means comprising means (95, 96, 97) for generating and modulating said synchronizing signals, a demodulation circuit (10) and a correlation circuit (51).
Claim 36
Dependent Claim
18 words
Apparatus according to claim 33, in which said modulation and demodulation means comprise circuits of the FSK type.
Claim 37
Dependent Claim
31 words
A coding apparatus according to claim 33, including manually actuatable means (64) for generating a control signal, and control means (60) responsive to said control signal for actuating said commutation means.
Claim 38
Dependent Claim
83 words
Apparatus according to claim 35, including second manually actuatable means (65, 66), said control means (60) being responsive to control signals from one ofsaid second manually actuatable means and output signals from said correlation circuit (51), said memory of said first means including a plurality of memory elements (23-26), said correlation circuit signals enabling the use of one memory element (23) of said memory elements, said one memory element (23) providing a transmission of said electric signal portions according to their reception order.
Claim 39
Dependent Claim
85 words
Apparatus according to claim 36, including a reception time base generator (53) and a transmission time base generator (79), said correlation circuit (51) generating an output signal coupled directly to said reception time base generator and indirectly to said transmission time base generator through a logic consent gate (54), said logic consent gate receiving further an output signal (82) from said control means (60) sensitive to one state of said apparatus relative to the operation of that apparatus as a main or an enslaved station.
Claim 40
Dependent Claim
176 words
Apparatus for the coding and decoding of electrical signals within a pre-established frequency band and useful for providing communication secrecy, which may be connected between means for the generation and reception of said electrical signals and means for the exchange of said coded signals with at least one other coding and decoding apparatus, comprising a transmission and coding circuit and a reception and decoding circuit for said signals, commutation means for complementarily enabling said transmission and coding circuit and said reception and decoding circuit, said circuits comprising first means for temporarily storing consecutively received portions of said electrical signals, and second means for enabling the operation of said first means to consecutively store in memory said signal portions and to transmit said signal portions, in a different order, to one of said exchange means and said means for the reception of said signals, including simplex/duplex communication means (300) for establishing one of simplex and duplex type communication with another coding apparatus and determining the presence of a corresponding simplex/duplex communication means in said another coding apparatus.
Claim 41
Dependent Claim
176 words
Apparatus for the coding and decoding of electrical signals within a pre-established frequency band and useful for providing communication secrecy, which may be connected between means for the generation and reception of said electrical signals and means for the exchange of said coded signals with at least one other coding and decoding apparatus, comprising a transmission and coding circuit and a reception and decoding circuit for said signals, commutation means for complementarily enabling said transmission and coding circuit and said reception and decoding circuit, said circuits comprising first means for temporarily storing consecutively received portions of said electrical signals, and second means for enabling the operation of said first means to consecutively store in memory said signal portions and to transmit said signal portions, in a different order, to one of said exchange means and said means for the reception of said signals, including simplex/duplex communication means (300) for establishing one of simplex and duplex type communication with another coding apparatus and determining the presence of a corresponding simplex/duplex communication means in said another coding apparatus.
Claim 42
Dependent Claim
86 words
Apparatus according to claim 38, including further means, enabled by said simplex/duplex communication means and comprising a first oscillator (163) for transmitting a first signal from a transmitting apparatus to a receiving apparatus, and a second oscillator (164) enabled, in said receiving apparatus, by said first signal, to transmit an advising signal to said transmitting apparatus, said first signal locking further in said receiving apparatus the activation of said first oscillator, and said simplex/duplex communication means including means for detecting said signals generated by said oscillators.
Claim 43
Dependent Claim
38 words
Apparatus according to claim 39, in which at least one of said first signal and said advising signal are transmitted through the enabling of at least one of said first and second oscillators by manually actuatable means (64).
Claim 44
Dependent Claim
36 words
Apparatus according to claim 39, in which said first signal and advising signal are transmitted by the enabling of a gating circuit (156) whose output signal is a function of the presence of said electrical signals.
Claim 45
Dependent Claim
33 words
Apparatus according to claim 39, in which said first signal is transmitted by the enabling of a gating circuit (156) whose output signal is a function of the presence of said electrical signals.
References Cited (Backward Citations)
US3937888A
Cited
US3105114A
Cited
US2913525A
Cited
US3731197A
Cited
US3657699A
Cited
US3773977A
Cited
US3824467A
Cited
US4087626A
Cited
US4086435A
Cited
US4100374A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-08-12 | 1984-02-11 | 1984-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-08-12 | 1988-02-11 | 1988-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-08-12 | 1992-02-11 | 1992-08-12 | $7700.00 | Window Closed / Lapsed |