Cooperative type anti-collision radio system

• US 4,104,638 A
• Filed: 06/23/1976
• Issued: 08/01/1978
• Est. Priority Date: 06/23/1976
• Status: Expired due to Term

• Current Assignee: Raymond R. Middleton
• Original Assignee: Raymond R. Middleton
• Inventors: Middleton, Raymond R.
• Primary Examiner(s): Wilbur, Maynard R.
• Assistant Examiner(s): Berger, Richard E.
• Application Number:
  US05/699,019
• Time in Patent Office: 769 Days
• Field of Search: 343/112 CA, 343/112 A, 325/22
• US Class Current: 342/455
• CPC Class Codes: G08G 5/0008 with other aircraft
• CPC Class Codes: G08G 5/0052 for cruising combined instruments indicating more than one navigational value G01C23/00
• CPC Class Codes: G08G 5/0078 for monitoring traffic from the aircraft radar or analogous systems specially adapted for traffic control G01S13/91

Abstract

A cooperative type aircraft anti-collision radio system utilizes radio transmitters and receivers transmitting and receiving on a single radio frequency common to most aircraft having radio systems or on multiple radio frequencies if desired. Each aircraft will be capable of transmitting at least one and preferably a plurality of selected tones which may be received by appropriate radio receiver circuitry of other aircraft operating in the vicinity. Conventional automatic direction finding circuitry ascertains the bearing of the aircraft transmitting a modulated tone or tones which is displayed for visual inspection. By interpreting changes in the bearing of the aircraft transmitting the tone or tones and/or by interpreting the strength of the signals being received a decision may be made whether or not evasive action is required in order to avoid a collision. The decision may also be made automatically by computer depending upon the degree of sophistication desired advising the pilot to fly his aircraft upwardly, downwardly, to the right, left, or level in order to avoid collision. For aircraft including both transmitter and receiver circuitry the transmitter and receiver are both operative through a plurality of switching circuits provided one for each of the tones being transmitted and received. The switching circuits are energized according to codes that are unique to each aircraft so the codes of two aircraft will never correspond exactly thereby assuring reception of at least one position signal between any two aircraft equipped with transmitting and receiving anti-collision radio systems.

Claims

1. An aircraft anti-collision radio system for sending and receiving radio transmissions on the same radio frequency, said system comprising radio transmitter circuitry continuously transmitting radio signals of at least one designated tone, radio receiver circuitry continuously receiving said radio signals of said designated tone, transmitting and receiving antenna circuitry means for said system, indicator circuitry means capable of being energized upon receiving radio signals of said designated tone through said receiver circuitry, switching circuitry means for selectively completing the circuitry between said transmitter circuitry and said antenna circuitry means in a first operative condition thereof whereby radio signals of said designated tone are transmitted from said antenna circuitry means and completing the circuitry between said receiver circuitry and said indicator circuitry means in a second operative condition thereof for receiving radio signals transmitted from other aircraft, means for sequentially actuating said switching circuitry means to said first and second positions thereof in response to a coded sequence that is different in said radio system from the coded sequence of all other aircraft having a similar anti-collision radio system, whereby said radio system is capable of intermittently transmitting and receiving radio signals of said designated tone through said transmitting and receiving antenna circuitry means.

2. An aircraft anti-collision radio system as set forth in claim 1, said means for actuating said switch means comprising switch actuating circuitry including a source of electrical potential, at least one intermittent contact means capable of completing and breaking said switch actuating circuitry in accordance with a repetitive coded sequence.

3. An aircraft anti-collision radio system according to claim 1, said transmitting circuitry continuously transmitting radio signals of a given frequency and of a plurality of designated tones, said radio receiver circuitry being capable of discriminating said plurality of tone signals and including a plurality of tone circuits each being energized by selected ones of said plurality of tone signals, said indicator circuit means comprising a plurality of indicators each being energized by a selected one of said tone signals, said switching circuitry means including a switching circuit connected to each of said tone circuits.

4. An aircraft anti-collision radio system according to claim 3, a plurality of distributor circuits being electrically connected to selected ones of said switching circuits, said distributor circuits each having means for completing and breaking the associated distributor circuit in accordance with a coded sequence, whereby said switching circuits are energized to the first or second conditions thereof in response to the coded sequence of the associated distributor circuit.

5. An aircraft anti-collision radio system according to claim 4;

aircraft identity code means including a plurality of code circuits connected to selected ones of said distributor circuits, said code means energizing and deenergizing said code sequence determined by said identity code means, whereby said distributor circuits are energized and cause energization of associated switching circuitry in accordance with the coded sequence of both said distributor means and said aircraft identity code means.

6. An aircraft anti-collision radio system as set forth in claim 1;

altitude transducer circuitry and altitude rate of change circuitry provided for said radio system, altitude tone modulation circuitry being electrically connected to said altitude transducer circuitry and said altitude rate of change transducer circuitry and being connected to said trannsmitter, whereby said transmitter will also transmit modulated tones reflecting the altitude and altitude rate of change;

altitude comparator circuitry connected to said receiver circuitry and being capable of comparing altitude signals received from other transmitters and comparing them with the altitude of the aircraft receiving the signals whereby a determination may be made whether or not the transmitting aircraft presents a hazard to operation of the receiving aircraft.

7. An aircraft anti-collision radio system as recited in claim 1;

a command computer circuit having a command display to advise as to an evasive maneuver desired, signal strength measuring and comparator circuitry being connected to said receiver circuitry and being operative to sense increase or decrease in the strength of the signal being received and to transmit information regarding the relative increase or decrease in signal strength to said command computer circuit, said command computer circuit upon receiving information indicating a predetermined increase in signal strength being operative to energize a portion of said command display to advise as to the particular evasive maneuver desired.

8. An aircraft anti-collision radio system comprising radio transmitter circuitry transmitting a plurality of designated tones on a radio carrier signal of at least one designated frequency, a plurality of transmitter tone conductors being connected to said transmitter circuitry, a radio receiver having a plurality of receiver tone circuits one for each of said tones transmitted by said transmitter tone circuits, transmitting and receiving antenna circuitry for said radio system, a plurality of indicator circuits one being provided for each of said tones transmitted by said transmitter tone circuits, a plurality of electrically energized switching circuits completing connection between said transmitter tone circuitry and said transmitting antenna circuitry in a first operative condition thereof whereby transmitted signals will be conducted to said transmitting antenna circuitry, said switching circuitry completing connection between said receiver tone circuitry and said indicator circuits in a second operative condition thereof whereby tone signals received and discriminated by said receiver circuitry will be conducted to appropriate ones of said indicator circuits, a plurality of distributor circuits being connected one to each of said switching circuits and being operative to complete and break said switching circuits in accordance with a predetermined repetitive sequence determined by said distributor means, aircraft identification code means being provided for each of said distributor circuits, a plurality of code circuits being provided for electrical connection between said aircraft identification code circuitry and said switching circuitry, said aircraft identification code means being connected to a source of electrical potential and being operative to intermittently energize said code circuits in reponse to the code sequence of said aircraft identification code circuitry whereby said switching circuitry will be energized responsive to the combined code sequences of said aircraft identification code circuitry and said distributor means.

9. An aircraft anti-collision radio system according to claim 8;

a command computer being connected to said receiver circuitry and having a command display, signal strength measuring circuitry being connected to said receiver circuitry and to said command computer, said signal strength measuring circuitry measuring relative increase or decrease in the field strength of the signal being received and transmitting signal strength information to said command computer, said command computer upon receiving information of a predetermined increase in the strength of the signals being received causing energization of a said command display to advise the pilot of the particular evasive maneuver desired.

10. An aircraft anti-collision radio system according to claim 8;

a command computer being connected to said receiver circuitry and having a command display, an altitude comparator circuit being connected to said receiver circuitry and also being connected to said command computer, said altitude comparator being operative to eliminate all altitude tone signals but the particular tone signals relevant to the altitude at which the receiving aricraft is operating and also being capable of transmitting appropriate received altitude tone signals to said command computer, said command computer receiving information from said altitude comparator circuit and energizing said command display in order to advise the pilot of a maneuver that would remove his aircraft from the danger of possible collision.

11. An aircraft anti-collision radio system according to claim 8;

an altitude tone modulation generator connected to said transmitter circuitry, an altitude transducer connected to said altitude tone modulation generator and being operative to transmit altitude tone signals to said altitude tone modulation generator whereby said transmitter will transmit coded signals indicating the particular altitude at which the aircraft is operating.

12. An aircraft anti-collision radio system according to claim 11;

an altitude rate of change transducer being connected to said altitude tone modulation generator and being operative to transmit signals to said altitude tone modulation generator thereby causing said transmitter to transmit signals indicating the rate of change in altitude of the aircraft.

13. An aircraft anti-collision radio system according to claim 8;

a command signal computer being connected to said transmitter circuitry, a command signal tone modulation generator being connected to said command signal computer and being responsive to a maneuver executed by the aircraft to transmit a command signal tone to said command signal computer, said command signal computer will in turn conduct signals to said transmitter resulting in the transmission of signals advising maneuvers if any to be executed by other aircraft operating in the area.