SYSTEMS FOR DETERMINING A REFERENCE SIGNAL AT ANY LOCATION ALONG A TRANSMISSION MEDIA

• US 20100124263A1
• Filed: 11/19/2008
• Published: 05/20/2010
• Est. Priority Date: 11/19/2008
• Status: Abandoned Application

• Current Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Original Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Inventors: Martin, G. Patrick, Ralston, Lynda Margaret, Hash, Ronald J.
• Application Number:
  US12/274,135
• Publication Number:
  US 20100124263A1
• Time in Patent Office: Days
• US Class Current: 375/224
• CPC Class Codes: G06F 1/10 Distribution of clock signals , e.g. skew
• CPC Class Codes: H04B 7/02 Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas RAKE receivers H04B1/7115

Abstract

Systems comprising sensing devices (SD), a signal combiner (SC), signal subtractors (SS), and signal multipliers (SM). SD (116, 402, 504, 604, 620, 708a, 708b, 708c) senses at a first location along a transmission media (TM) a first signal (V_f) propagated over TM (100, 502, 602, 702, 1025) in a forward direction and a second signal (V_r) propagated over TM in a reverse direction opposed from the forward direction. SC (406, 508, 606, 806) computes a Sum signal (S) by adding V_f and V_r together. A first SS (408, 508, 606, 806) computes a Difference signal (D) by subtracting V_r from V_f. A first SM (410, 510, 608a, 808a) computes a first Exponentiation signal (E_S) using S. A second SM (412, 512, 608b, 808b) computes a second Exponentiation signal (E_D) using D. A second SS (414, 514, 614, 816) subtracts E_S from E_D to obtain a reference signal (V_ref).

Claims

1. A system, comprising:

at least one first sensing device configured for sensing at a first location along a transmission media a first signal propagated over the transmission media in a forward direction and a second signal propagated over the transmission media in a reverse direction opposed from the forward direction, the second signal being a reflected version of the first signal;

a first signal combiner communicatively coupled to the first sensing device and configured for computing a first sum signal by adding the first and second signals together;

a first signal subtractor communicatively coupled to the first sensing device and configured for computing a first difference signal by subtracting the second signal from the first signal;

a first signal multiplier communicatively coupled to the first signal combiner and configured for computing a first exponentiation signal using the first sum signal;

a second signal multiplier communicatively coupled to the first signal subtractor and configured for computing a second exponentiation signal using the first difference signal; and

a second signal subtractor communicatively coupled to the first and second signal multipliers and configured for subtracting the first exponentiation signal from the second exponentiation signal to obtain a first reference signal.

2. The system according to claim 1, wherein the first reference signal has a first frequency equal to a second frequency of the first signal.

3. The system according to claim 1, wherein the first reference signal has a first frequency different than a second frequency of the first signal.

4. The system according to claim 3, further comprising at least one post processing device configured for processing the first reference signal to obtain an adjusted reference signal with a third frequency equal to the second frequency of the first signal.

5. The system according to claim 4, wherein the at least one post processing device comprises at least one device selected from the group consisting of a phase lock loop, a frequency divider, a phase locked oscillator.

6. The system according to claim 1, wherein the transmission media is selected from the group consisting of free space, a waveguide, a coaxial transmission line, an optical fiber, and an acoustic media.

7. The system according to claim 1, wherein the first sensing device is selected from the group consisting of a transducer and a directional coupler.

8. The system according to claim 1, wherein the first sensing device comprises a directional coupler and a fiber demodulator.

9. The system according to claim 1, wherein the first signal combiner and the first signal subtractor collectively comprise a sum-diff hybrid circuit.

10. The system according to claim 9, wherein the sum-diff hybrid circuit is a 180 degree hybrid coupler.

11. The system according to claim 1, wherein the second signal subtractor is a 180 degree hybrid coupler.

12. The system according to claim 1, further comprising at least one phase and amplitude trimmer.

13. The system according to claim 1, further comprising

at least one second sensing device configured for sensing at a second location different from the first location along the transmission media the first and second signal;

and

a reference signal generator configured for computing a second reference signal using the first and second signals sensed at the second location;

wherein the second reference signal is the same as the first reference signal.

14. The system according to claim 13, wherein the reference signal generator is further configured for computing a second sum signal by adding the first and second signals sensed at the second location together, computing a second difference signal by subtracting the second signal sensed at the second location from the first signal sensed at the second location, computing a third exponentiation signal using the second sum signal, computing a fourth exponentiation signal using the second difference signal, and subtracting the third exponentiation signal from the fourth exponentiation signal to obtain the second reference signal.

15. A system, comprising:

at least one first sensing device configured for sensing at a first location along a transmission media a first signal propagated over the transmission media in a forward direction and a second signal propagated over the transmission media in a reverse direction opposed from the forward direction, the second signal being a reflected version of the first signal;

a first hybrid coupler communicatively coupled to the first sensing device and configured for computing a first sum signal by adding the first and second signals together and a first difference signal by subtracting the second signal from the first signal;

a first signal multiplier communicatively coupled to the first hybrid coupler and configured for computing a first exponentiation signal using the first sum signal;

a second signal multiplier communicatively coupled to the first hybrid coupler and configured for computing a second exponentiation signal using the first difference signal; and

a second hybrid coupler communicatively coupled to the first and second signal multipliers and configured for subtracting the first exponentiation signal from the second exponentiation signal to obtain a first reference signal.

16. The system according to claim 15, wherein the first sensing device is selected from the group consisting of a transducer and a directional coupler.

17. The system according to claim 15, further comprising at least one phase and amplitude trimmer.

18. A communication system, comprising:

at least one first sensing device configured for sensing at a first location along a transmission media a first signal propagated over the transmission media in a forward direction and a second signal propagated over the transmission media in a reverse direction opposed from the forward direction, the second signal being a reflected version of the first signal; and

at least one reference signal generator communicatively coupled to the first sensing device and configured for computing a first sum signal by adding the first and second signals together, computing a first difference signal by subtracting the second signal from the first signal, computing a first exponentiation signal using the first sum signal, computing a second exponentiation signal using the first difference signal, and subtracting the first exponentiation signal from the second exponentiation signal to obtain a reference signal.

19. The communication system according to claim 18, wherein the transmission media is selected from the group consisting of free space, a waveguide, a coaxial transmission line, an optical fiber, and an acoustic media.

20. The communication system according to claim 18, further comprising a phase comparator for determining a phase offset by comparing a phase of a transmit signal to a phase of the reference signal.