Voice and data encryption device

• US 5,410,599 A
• Filed: 05/14/1993
• Issued: 04/25/1995
• Est. Priority Date: 05/15/1992
• Status: Expired due to Term

• Current Assignee: John J. Crowley
• Original Assignee: TecSec, Incorporated
• Inventors: Wickham, Michael J., Crowley, John J.
• Primary Examiner(s): CANGIALOSI, SALVATORE A
• Application Number:
  US08/061,327
• Time in Patent Office: 711 Days
• Field of Search: 380/9, 380/18, 380/21, 380/25, 380/49, 380/2
• US Class Current: 380/269
• CPC Class Codes: H04K 1/00 Secret communication

Abstract

A portable voice and data encryption device designed to be used with normal wideband telephone and cellular telephones, computers and facsimile machines to transmit voice and data in encrypted form. The V/DED comprises a voice and data encryption module, an encryption and control module, and a modem module. The modem module can adapt its data rate to account for the changes in the signal strength between the sending and receiving sites. The encryption and control module senses the change in data rate of the modem module during transmission and synchronizes the activities of the voice and data module so that the amount of data being produced for encryption and transmission matches the data rate being experienced by the modem module. The V/DED very simply connects to the wall jack of a normal PSTN with the computer, telephone, or facsimile machine plugging directly into the V/DED.

Claims

1. A portable voice and data encryption device, comprising:

A) input means for accepting input signals from and providing received signals to communications equipment;

B) voice/data processing means, connected to the input means, for digitizing voice input signals and for compressing digitized voice input signals and digital input signals to provide compressed digital data, and further for decompressing received compressed data and for recovering analog signals, providing the received signals for the communications equipment;

C) encryption/decryption and control means, connected to the voice/data processing means, for encrypting the compressed digital data to provide output data and for decrypting received encrypted digital data, providing the received compressed data, and further for providing control signals to the voice/data processing means;

D) modem means, connected to the encryption/decryption and control means, for preparing the output data for transmission and for accepting the received encrypted digital data; and

E) output means, connected to the modem means, for receiving the received encrypted digital data from and transmitting the output data to a telephony network.

2. The portable voice and data encryption device of claim 1, wherein the telephony network is a public/private switched telephone network.

3. The portable voice and data encryption device of claim 1, wherein the telephony network is a cellular telephone network.

4. The portable voice and data encryption device of claim 1, wherein the telephony network is a local area network.

5. The portable voice and data encryption device of claim 1, wherein said voice/data processing means comprises a filter means for filtering the input signals to increase a ratio of signal to noise of the input signals.

6. The portable voice and data encryption device of claim 5, wherein the encryption/decryption and control means comprises a software implemented data encryption algorithm and software implemented decryption algorithm.

7. The portable voice and data encryption device of claim 6 wherein said modem means comprises a stored communication protocol for controlling data communication over private switched telephone networks, cellular communications networks, and local area networks.

8. The portable voice and data encryption device of claim 1 wherein said communications equipment is telephone communications equipment selected from the group consisting of cellular telephone equipment and wideband telephone equipment connected to a PSTN.

9. The portable voice and data encryption device of claim 5 wherein said encryption/decryption and control means comprises a firmware implemented data encryption algorithm.

10. The portable voice and data encryption device of claim 1 wherein said communications equipment is selected from the group of equipment consisting of unmodified telephone equipment, computers, and facsimile machines.

11. A portable voice and data encryption device, comprising:

A) input means comprising means for accepting analog voice input signals from unmodified telephone equipment;

B) a voice/data processing module, connected to the input means, the voice/data processing module comprising;

1) filter means for filtering the input signals to increase a ratio of signal to noise of the input signals;

2) first conversion means for converting the analog input signals to digitized signals; and

3) compression means for compressing the digitized signals;

C) an encryption/decryption and control module, connected to the voice/data processing module, the encryption/decryption and control module comprising;

1) means for accepting the compressed digitized signals from the voice/data processing module;

2) encryption means for encrypting the compressed digitized signals to provide output data; and

3) control means for providing control signals for controlling operation of the voice/data processing module and the encryption means;

D) a modem module, connected to the encryption/decryption and control module, for preparing the output data for transmission under direction of the control signals; and

E) output means connected to the modem module, comprising means for transmitting the output data to a telephony network.

12. The portable voice and data encryption device of claim 11, wherein:

A) the input means further comprises means for accepting digital input data from communications equipment; and

B) the encryption/decryption and control module further comprises means for accepting filtered digital input data and means for encrypting the filtered digital input data;

C) the output data comprising the encrypted digital input data and the compressed digitized signals.

13. The portable voice and data encryption device of claim 12, wherein:

A) the output means further comprises means for receiving encrypted data from a telephony network;

B) the modem module further comprises means for preparing the encrypted data for processing;

C) the encryption/decryption and control module further comprises;

1) means for accepting the encrypted data from the modem module; and

2) decryption means for decrypting the encrypted data to provide decrypted data;

D) the voice/data processing module further comprises;

2) decompression means for decompressing the decrypted data; and

3) second conversion means for converting the decrypted data to analog signals to provide received data; and

E) the input means further comprises means for accepting the received data from the voice/data processing module and for providing the received data to the unmodified telephone equipment and the communications equipment.

14. The portable voice and data encryption device of claim 12, wherein the encryption/decryption and control module further comprises a software implemented encryption algorithm.

15. The portable voice and data encryption device of claim 12, wherein the encryption/decryption and control module further comprises a firmware implemented encryption algorithm.

16. The portable voice and data encryption device of claim 12, wherein the modem module comprises a stored communications protocol for controlling data communication over private switched telephone networks, cellular communications networks, and local area networks.

17. A method of providing secure communications, comprising the steps of:

A) accepting analog voice signals and digital data from communications equipment;

B) filtering the analog voice signals and digital data to increase the signal to noise ratio of the analog voice signals and digital data;

C) digitizing the analog voice signals to provide a digitized signal;

D) compressing the digitized signal and compressing any uncompressed digital data to provide a compressed digital signal;

E) encrypting the compressed digital signal to provide an encrypted output signal;

F) modulating the encrypted output signal for transmission over a telephony network; and

G) transmitting the encrypted output signal over the telephony network.

18. The method of claim 17, further including the steps of:

A) receiving an encrypted input signal over a telephony network;

B) demodulating the encrypted input signal;

C) decrypting the demodulated encrypted input signal to provide a decrypted input signal;

D) decompressing the decrypted input signal;

E) recovering an analog voice component of the decrypted input signal to provide an analog voice input signal and digital input data; and

F) providing the analog voice input signal and digital input data to communications equipment.

19. The method of claim 17, wherein the step of accepting analog voice signals and digital data from communications equipment includes the steps of accepting analog voice signals from unmodified telephone equipment and accepting digital data from a computer and a facsimile device.

20. The method of claim 18, wherein the step of providing the analog voice input signal and digital input data to communications equipment includes the steps of providing the analog voice input signal to unmodified telephone equipment and providing digital input data to a computer and a facsimile device.