406 MHz emergency beacon with in-band homing transmitter

• US 20040087284A1
• Filed: 06/30/2003
• Published: 05/06/2004
• Est. Priority Date: 11/01/2002
• Status: Abandoned Application

• Current Assignee: William A. Street
• Original Assignee: William A. Street
• Inventors: Street, William A.
• Application Number:
  US10/608,181
• Publication Number:
  US 20040087284A1
• Time in Patent Office: Days
• US Class Current: 455/125
• CPC Class Codes: G01S 1/68 Marker, boundary, call-sign, or like beacons transmitting signals not carrying directional information
• CPC Class Codes: G01S 5/0226 Transmitters

Abstract

A search and rescue beacon includes a main transmitter transmitting a Cospas-Sarsat signal at a main frequency and an auxiliary homing transmitter transmitting a homing signal at a homing frequency close to the main frequency. Advantageously both the Cospas-Sarsat signal and the homing signal are generated by a single synthesizer switching between a main Cospas-Sarsat burst transmission and a continuous homing frequency transmission of the homing signal. The Cospas-Sarsat signal is advantageously transmitted at a higher power than the homing signal. The single synthesizer may use a single amplifier chain. The single synthesizer and amplifier chain may use a single antenna.

Claims

1. A search and rescue beacon comprising a main transmitter transmitting a Cospas-Sarsat signal at a main frequency and an auxiliary homing transmitter transmitting a homing signal at a homing frequency close to said main frequency.

2. The beacon of claim 1 wherein both said Cospas-Sarsat signal and said homing signal are generated by a single synthesizer switching between a main Cospas-Sarsat burst transmission and a continuous homing frequency transmission of said homing signal.

3. The beacon of claim 1 wherein said main frequency is within the 406-406.1 MHz band.

4. The beacon of claim 2 wherein said main frequency is within the 406-406.1 MHz band.

5. The beacon of claim 3 wherein said homing frequency is dedicated in a lower part of a 406-406.1 MHz frequency band.

6. The beacon of claim 3 wherein said homing frequency is dedicated in an upper part of a 406-406.1 MHz frequency band.

7. The beacon of claim 4 wherein said homing frequency is dedicated in a lower part of a 406-406.1 MHz frequency band.

8. The beacon of claim 4 wherein said homing frequency is dedicated in an upper part of a 406-406.1 MHz frequency band.

9. The beacon of claim 2 wherein said single synthesizer uses a single amplifier chain.

10. The beacon of claim 9 wherein said single synthesizer and amplifier chain use a single antenna.

11. The beacon of claim 1 wherein said homing signal is transmitted at a lower power than said Cospas-Sarsat signal.

12. The beacon of claim 11 wherein said homing signal is transmitted at approximately 50 milli-watts.

13. The beacon of claim 2 wherein said homing signal is transmitted at a lower power than said Cospas-Sarsat signal.

14. The beacon of claim 13 wherein said homing signal is transmitted at approximately 50 milli-watts.