Secure SCA broadcasting system including subscriber actuated portable receiving terminals

• US 4,196,310 A
• Filed: 11/03/1977
• Issued: 04/01/1980
• Est. Priority Date: 04/09/1976
• Status: Expired due to Term

• Current Assignee: Digital Data Incorporated (PetIQ, Inc.)
• Original Assignee: Digital Data Incorporated (PetIQ, Inc.)
• Inventors: Schultz, John F., Schultz, Charles A. Jr., Forman, Aubry S.
• Primary Examiner(s): Engle, Samuel W.
• Assistant Examiner(s): Cangialosi, S. A.
• Application Number:
  US05/848,269
• Time in Patent Office: 880 Days
• Field of Search: 178/22, 340/154, 340/149 R
• US Class Current: 380/46
• CPC Class Codes: H04H 20/34 using an out-of-band subcarrier signal
• CPC Class Codes: H04H 40/18 Arrangements characterised by circuits or components specially adapted for receiving
• CPC Class Codes: H04H 60/27 Arrangements for recording or accumulating broadcast information or broadcast-related information
• CPC Class Codes: H04L 12/1804 for stock exchange and similar applications

Abstract

A secure information broadcasting system including a central transmitting station for encoding data in binary form utilizing a keyword and transmitting a FM-SCA signal phase shift modulated by the encoded data. Each of a plurality of portable receiving terminals has an identification number stored therein. When a subscriber desires to display the broadcast information on his terminal, he enters a unique password which is combined with the identification number to generate the keyword. The keyword is utilized to decode the received binary data. The portable terminal includes a receiver for decoding the phase shifted FM-SCA signal into the encoded binary data; a keyboard for entering the password, information and display commands; an alpha-numeric data display; a processor responsive to the inputs from the receiver and the keyboard for performing selected arithmetic and logic operations to generate output data to the data display and a bus connecting the circuits of the portable terminal for parallel signal flow.

Claims

1. A secure information broadcasting system including a transmitting station for encoding as binary coded bits data received from an information source, for modulating a carrier wave with the data bits and for transmitting the modulated carrier wave and a plurality of portable terminals for receiving and selectively displaying the data, each of said portable terminals comprising:

receiver means for separating the modulation signal from the carrier wave and generating the encoded binary data bits from the modulation signal;

keyboard means for generating a binary coded password individual to each of said portable terminals;

storage means for generating a binary coded identification number individual to each of said portable terminals; and

processing means responsive to said password and said identification number for generating a binary coded keyword having a predetermined number of bits, said processing means being responsive to said keyword and a number of said encoded binary data bits equal to said predetermined number for decoding said encoded binary data bits.

2. A system according to claim 1 wherein said processing means rotates said keyword by one bit after said number of said encoded binary data bits are decoded.

3. A system according to claim 1 wherein said processing means is responsive to said password for generating a pseudo random number and exclusive-OR'"'"'s said pseudo random number and said identification number to generate said keyword.

4. A system according to claim 3 wherein a first one of said number of said encoded binary data bits is decoded to generate a seed number, said processing means is responsive to said seed number for generating a second pseudo random number and said processing means exclusive-OR'"'"'s said second pseudo random number and a second one of said number of said encoded binary data bits to decode said encoded binary data bits.

5. A system according to claim 1 wherein said decoded encoded binary data bits represent stock market quotation information.

6. A method for providing subscriber access to binary coded data in a secure information broadcasting system comprising the steps of:

a. generating encoded binary data by exclusive-OR'"'"'ing said binary coded data with a binary coded keyword;

b. transmitting said encoded binary data from a transmitting station;

c. receiving said encoded binary data at a plurality of subscriber receiving terminals;

d. exclusive-OR'"'"'ing a subscriber generated binary coded password with a binary coded identification number to generate said keyword, said password and said identification number individual to each of said receiving terminals; and

e. exclusive-OR'"'"'ing said keyword with said encoded binary data to decode said encoded binary data into said binary coded data.

7. A method for providing subscriber access to binary coded data in a secure information broadcasting system comprising the steps of:

a. generating encoded binary data by exclusive-OR'"'"'ing said binary coded data with a binary coded keyword;

b. transmitting said encoded binary data from a transmitting station;

c. receiving said encoded binary data at a plurality of subscriber receiving terminals;

d. seeding a random number generator with a subscriber generated binary coded password to generate a first binary coded pseudo random number, said password individual to each of said receiving terminals;

e. exclusive-OR'"'"'ing said first pseudo random number with a binary coded identification number to generate said keyword, said identification number individual to each of said receiving terminals;

f. exclusive-OR'"'"'ing said keyword with a first portion of said encoded binary data to generate a binary coded seed number;

g. seeding said random number generator with said seed number to generate a second binary coded pseudo random number; and

h. exclusive-OR'"'"'ing said second pseudo random number with a second portion of said encoded binary data to decode said second portion into said binary coded data.