Digital radio with security system for selectively enabling software controlled options

• US 4,941,174 A
• Filed: 04/19/1988
• Issued: 07/10/1990
• Est. Priority Date: 04/19/1988
• Status: Expired due to Term

• Current Assignee: Com-Net Ericsson Canada Corp., Com-Net Ericsson Critical Radio Systems, Inc., General Electric Company
• Original Assignee: General Electric Company
• Inventors: Ingham, Scott W.
• Primary Examiner(s): Tarcza, Thomas H.
• Assistant Examiner(s): Cain, David
• Application Number:
  US07/183,212
• Time in Patent Office: 812 Days
• Field of Search: 380/52, 380/23, 380/25, 380/48, 380/4, 340/825.31, 340/825.5, 364/222.5, 364/929.2, 364/929.4
• US Class Current: 380/52
• CPC Class Codes: H04B 1/38 Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving

Abstract

Different digital radio transceiver front panel escutcheon plate modules are provided for different optional transceiver configurations. A security circuit is provided in each module in addition to user controls and associated circuitry. The security circuit is connected to communicate serial data signals to and from a digital signal controller which is part of the main transceiver circuitry. The controller is capable of performing any of various basic and option functions under control of program control instructions stored in an associated non-volatile memory. Upon initial application of power to the transceiver, the controller transmits a sequence of digital signals to the security circuit. The security circuit permutes the sequence of signals into a different sequence, the specific permutation used being arbitrarily complex--and dependent on transceiver "option" features to be enabled. The security circuit communicates the permuted signal sequence back to the controller. The controller enables (executes) portions of the program control instructions stored in its associated non-volatile memory and disables (does not execute) other portions of the stored program control instructions in response to the sequence received from the security circuit.

Claims

1. An escutcheon plate module adapted for connection to a digital radio transceiver of the type which generates clock synchronization signals and applies said clock synchronization signals to an electrical connector, said module comprising:

connection means for separable engaging with said digital radio transceiver connector;

user control means connected to said connection means for applying control signals to said connection means in response to user manipulation thereof; and

security circuit means connected to receive said clock synchronization signals via said connection means for applying a predictable sequence of serial output signals to said connection means in timed relation with the occurrence of said clock synchronization signals.

2. A module as in claim 1 wherein:

said connection means includes a first electrical pin;

said user control means applies a first electrical signal to said first pin in response to said user manipulation; and

said security circuit means also applies said sequence of output signals to said first pin.

3. A module as in claim 1 wherein said security circuit means includes means for processing input date signals applied thereto by said digital radio transceiver to produce said sequence of serial output signals.

4. A module as in claim 1 wherein said security circuit includes:

output latch means for latching signals applied thereto in response to the occurrence of said clock synchronization signals and for applying said latched signals to said connection means as said sequence of output signals; and

logic gate array means responsive to said latched signals for generating signals to be subsequently latched by said output latch means.

5. A module as in claim 4 wherein said logic gate array means includes means for processing input data provided by said digital radio transceiver in accordance with a "sum of products" Boolean logic equation.

6. A module as in claim 5 wherein said logic array means includes means for combining a plurality of terms with the OR Boolean logic function and means for generating said plurality of terms from input signals with the AND Boolean logic function, at least one of said input signals being generated by said digital radio transceiver, the remainder of said input signals being provided by said output latch means.

7. An escutcheon plate module adapted for connection to a digital radio transceiver of the type which includes a multi-pin electrical connector including first, second and third pins, said escutcheon plate module comprising:

connector means for electrically connecting with said digital radio transceiver connector first, second and third pins;

user control means connected to said connector means for applying first, second and third control signals to said first, second and third pins in response to user manipulation thereof; and

security circuit means connected to said first, second and third pins via said connector means for receiving said clock synchronization signals present on said first pin, for receiving a sequence of input data signals present on said second pin, for permuting said input data signals to thereby generate a sequence of corresponding output signals, and for applying said output signal sequence to said third pin via said connector means in timed response to said clock synchronization signals.

8. In a digital radio transceiver of the type which includes a multi-pin electrical connector including first, second and third pins, a method of selectively enabling and disabling option features comprising:

(1) electrically connecting with said digital radio transceiver connector firs, second and third pins;

(2) applying a first control signal to said first pin in response to a first user manipulation;

(3) applying a second control signal to said second pin in response to a second user manipulation;

(4) applying a third control signal to said third pin in response to a third user manipulation;

(5) receiving clock synchronization signals present on said first pin;

(6) receiving a sequence of input date signals present on said second pin;

(7) permuting said input data signals to thereby generate a sequence of corresponding output signals;

(8) applying said output signal sequence to said third pin via said connector means in timed response to said clock synchronization signals; and

(9) enabling said digital radio transceiver to perform a first set of functions and disabling said digital radio transceiver from performing a second set of functions in response to the identity of said output signal sequence.

9. In a digital radio transceiving system for transmitting and receiving radio frequency signals of the type including a microprocessor for performing first and second radio transceiving functions in response to program control instructions stored in a memory associated therewith, a method of operating said system comprising the following steps:

(a) applying a serial stream of digital input signals from said microprocessor to a security circuit operatively connected thereto;

(b) receiving a responsive serial digital output signal stream from said security circuit with said microprocessor;

(c) comparing said received serial digital output signal stream with a first digital value predetermined by said serial digital input signal stream;

(d) If said comparing step (c) reveals said serial digital output signal stream matches said first value, enabling said first radio transceiving function;

(e) if said comparing step (c) reveals said serial digital output signals do not match said first value, disabling said first radio transceiving function; and

(f) enabling said second radio transceiving function regardless of the results of said comparing step (c).

10. A digital radio transceiving system including:

radio frequency means for transmitting and receiving radio frequency signals on radio frequency channels, and

a microprocessor, connected to control said radio frequency means and responsive to predetermined program control instructions, said microprocessor including;

means for applying serial digital input signals to a security circuit operatively connected thereto,

means for receiving serial digital output signals from said security circuit,

means for comparing said received serial digital output signals with a value predetermined by said serial digital input signals,

means for enabling said radio frequency means to operate of any RF channel within a first set of preprogrammed radio frequency channels and for also enabling said radio frequency means to operate on any RF channel within a second set of preprogrammed radio frequency channels if said comparing means reveals said serial digital output signals match said predetermined value, and

means for enabling said radio frequency means to operate on any RF channel within said first set of preprogrammed radio frequency channels and for disabling said radio frequency means from operating on channels within said second set of preprogrammed RF channels if said comparing means reveals said serial digital output signals do not match said predetermined value.

11. An escutcheon plate for disengageably connecting to the front panel of a radio frequency transceiver, said escutcheon plate comprising:

a particular configuration of user control means for controlling said transceiver to perform basic radio transceiving functions and additional optional radio transceiving functions associated with said particular configuration;

security circuit means for receiving a serial digital signal input from said transceiver, for permuting said serial digital signal input to a serial digital signal output corresponding to said particular user control means configuration, and for communicating said serial digital signal output to said transceiver to enable said transceiver to perform said additional optional radio transceiving functions, and

electrical connecting means for electrically connecting said user control means and said security circuit means to said radio frequency transceiver.