Dynamic Polarization Modulation and Control

• US 20130279631A1
• Filed: 02/19/2013
• Published: 10/24/2013
• Est. Priority Date: 02/17/2012
• Status: Active Grant

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Bowers, Steven, Hajimiri, Seyed Ali, Dasgupta, Kaushik, Tabbalvandani, Amirreza Safaripour
• Granted Patent: US 9,686,070 B2
• Time in Patent Office: Days
• US Class Current: 375/300
• CPC Class Codes: H01Q 21/245 provided with means for varying the polarisation polarising devices H01Q15/24; tracking by comparing linear polarisation compounds G01S3/146; reducing depolarisation effects H04B7/00; polarisation diversity H04B7/10
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• CPC Class Codes: H04L 27/04 Modulator circuits; Transmitter circuits
• CPC Class Codes: H04L 27/20 Modulator circuits; Transmitter circuits
• CPC Class Codes: H04L 5/04 the signals being represented by different amplitudes or polarities, e.g. quadriplex

Abstract

A method for sending a data from an electromagnetic radiator by polarization modulation of an electromagnetic wave includes radiating from the radiator first and second electromagnetic waves including first and second polarizations respectively, the first polarization being different than the second polarization. The first and second electromagnetic waves form a third electromagnetic wave having a third polarization different from the first or second polarization. The method includes modulating the third polarization responsive to the data by modulating one or more parts of the third electromagnetic wave. The data is sent in the third polarization. A system for sending a data includes an oscillator adapted to generate an oscillating signal, and a phase shifter coupled to the oscillator and adapted to generate a first phase-shifted oscillating signal having a first phase. The phase shifter is adapted to vary the phase difference across a predefined range in response to the data.

Claims

1. A method for sending a data from an electromagnetic radiator by polarization modulation of an electromagnetic wave, the method comprising:

radiating from the radiator a first electromagnetic wave including a first polarization;

radiating from the radiator a second electromagnetic wave including a second polarization different than the first polarization, the first and second electromagnetic waves forming a third electromagnetic wave having a third polarization different from the first or second polarization; and

modulating the third polarization responsive to the data by modulating one or more parts of the third electromagnetic wave, wherein the data is sent in the third polarization.

2. The method of claim 1, wherein the first electromagnetic wave includes a first phase and the second electromagnetic wave includes a second phase, wherein the one or more parts are selected from the group consisting of the first phase, and the second phase.

3. The method of claim 1, wherein the first electromagnetic wave includes a first amplitude and the second electromagnetic wave includes a second amplitude, wherein the one or more parts are selected from the group consisting of the first amplitude, and the second amplitude.

4. The method of claim 1, wherein the first electromagnetic wave includes a first phase and a first amplitude and the second electromagnetic wave includes a second phase and a second amplitude, wherein the one or more parts are selected from the group consisting of the first phase, the second phase, the first amplitude, and the second amplitude.

5. The method of claim 1, wherein the first electromagnetic wave includes a first phase and a first amplitude and the second electromagnetic wave includes a second phase and a second amplitude, wherein modulating one or more parts includes simultaneously modulating the first phase, the second phase, the first amplitude, and the second amplitude.

6. The method of claim 1 further comprising:

setting the first polarization to a clock-wise circular polarization; and

setting the second polarization to a counter-clock-wise circular polarization.

7. The method of claim 1 further comprising:

setting the first polarization to a first linear polarization having a first angle; and

setting the second polarization to a second linear polarization having a second angle substantially perpendicular to the first angle.

8. The method of claim 1, wherein the third polarization is a linear polarization.

9. The method of claim 1, wherein the third polarization is an elliptical polarization.

10. The method of claim 1 further comprising:

setting a first amplitude of the first electromagnetic wave equal to a second amplitude of the second electromagnetic wave;

setting the first polarization to a clock-wise circular polarization;

setting the second polarization to a counter-clock-wise circular polarization, wherein the one or more parts includes a first phase of the first electromagnetic wave and a second phase of the second electromagnetic wave, the third polarization being a linear polarization having an angle; and

modulating the angle responsive to a difference between the first and second phase, the difference being responsive to the data.

11. The method of claim 10, wherein the angle corresponds to a symbol representing the data.

12. The method of claim 10, wherein the symbol sends a single bit of information at a time.

13. The method of claim 10, wherein the symbol sends a plurality of bits of data simultaneously in time.

14. The method of claim 1 further comprising:

setting a first phase of the first electromagnetic wave equal to a second phase of the second electromagnetic wave;

setting the first polarization to a clock-wise circular polarization;

setting the second polarization to a counter-clock-wise circular polarization, wherein the one or more parts includes a first amplitude of the first electromagnetic wave and a second amplitude of the second electromagnetic wave, the third polarization being an elliptical polarization having a polarization ratio; and

modulating the polarization ratio responsive to the data.

15. The method of claim 14, wherein the polarization ratio is a quotient of the first amplitude divided by the second amplitude.

16. The method of claim 14, wherein the polarization ratio corresponds to a symbol representing the data.

17. The method of claim 16, wherein the symbol sends a single bit of information at a time.

18. The method of claim 16, wherein the symbol sends a plurality of bits of data simultaneously in time.

19. A method for receiving a data from an electromagnetic receiver by polarization demodulation of an electromagnetic wave, the method comprising:

receiving from an antenna a first signal having a first polarization and a second signal having a second polarization, the first and second signals being associated with the electromagnetic wave, the electromagnetic wave including a third polarization;

determining an amplitude of the first signal;

determining an amplitude of the second signal; and

determining an angle of the third polarization to receive the data.

20. The method of claim 19, wherein the first and second polarizations are linear.

21. The method of claim 20, wherein the first and second polarizations are substantially orthogonal.

22. The method of claim 19, wherein determining the angle includes calculating a quotient of the amplitude of the second signal divided by the amplitude of the first signal.

23. A system for sending a data from a radiator by polarization modulation of an electromagnetic wave comprising:

an oscillator adapted to generate an oscillating signal; and

a phase shifter coupled to the oscillator and adapted to generate a first phase-shifted oscillating signal having a first phase, wherein a phase difference exists between the first phase and the oscillating signal, wherein the phase shifter is further adapted to vary the phase difference across a predefined range in response to the data.

24. The system of claim 23, wherein the phase shifter is further adapted to generate a second phase-shifted oscillating signal having a second phase, wherein a phase difference between the first phase and the second phase defines the phase difference.

25. The system of claim 23 further comprising a radiator adapted to accept the first phase-shifted oscillating signal and the oscillating signal and respectively radiate a first electromagnetic wave having a first circular polarization and a second electromagnetic wave having a second circular polarization different than the first circular polarization, the first electromagnetic wave and the second electromagnetic wave adapted to form a third electromagnetic wave having linear polarization and having an angle, the angle being responsive to the data.

26. The system of claim 25, wherein the radiator includes an antenna positioned substantially in a plane defined by a first direction and a second direction orthogonal to the first direction, the antenna being symmetric about a center in the first direction and in the second direction, the antenna including a first port positioned at an edge of the antenna in the first direction and a second port positioned at an edge of the antenna in the second direction.

27. The system of claim 25, wherein the radiator includes a first antenna adapted to radiate the first electromagnetic wave and second antenna adapted to radiate the second electromagnetic wave.

28. The system of claim 25, wherein the angle corresponds to a symbol representing the data.

29. The system of claim 28, wherein the symbol sends a single bit of information at a time.

30. The system of claim 28, wherein the symbol sends a plurality of bits of data simultaneously in time.

31. A system for sending a data from a radiator by polarization modulation of an electromagnetic wave comprising:

a first circuit adapted to generate a first signal and a second signal;

an oscillator adapted to generate an oscillating signal;

a phase shifter coupled to the oscillator and adapted to generate a first phase-shifted oscillating signal and a second phase-shifted oscillating signal having a phase difference therebetween, wherein the phase shifter is adapted to vary the phase difference across a predefined range in response to the data;

a first frequency converter coupled to the phase shifter and the first circuit, the first frequency converter adapted to convert a frequency of the first signal in response to the first phase-shifted oscillating signal to generate a first frequency converted signal; and

a second frequency converter coupled to the phase shifter and the first circuit, the second frequency converter adapted to convert a frequency of the second signal in response to the second phase-shifted oscillating signal to generate a second frequency converted signal.

32. The system of claim 31 further comprising a radiator adapted to accept the first and second frequency converted signals and respectively radiate a first electromagnetic wave having a first polarization and a second electromagnetic wave having a second polarization different than the first polarization, the first electromagnetic wave and the second electromagnetic wave adapted to form a third electromagnetic wave having a third polarization, the third polarization modulated by one or more parts of the combined electromagnetic wave responsive to the data.

33. The system of claim 32, wherein the first electromagnetic wave includes a first phase and the second electromagnetic wave includes a second phase, wherein the one or more parts are selected from the group consisting of the first phase, and the second phase.

34. The system of claim 32, wherein the first electromagnetic wave includes a first amplitude and the second electromagnetic wave includes a second amplitude, wherein the one or more parts are selected from the group consisting of the first amplitude, and the second amplitude.

35. The system of claim 32, wherein the first electromagnetic wave includes a first phase and a first amplitude and the second electromagnetic wave includes a second phase and a second amplitude, wherein the one or more parts are selected from the group consisting of the first phase, the second phase, the first amplitude, and the second amplitude.

36. The system of claim 32, wherein the first electromagnetic wave includes a first phase and a first amplitude and the second electromagnetic wave includes a second phase and a second amplitude, wherein modulating one or more parts includes simultaneously modulating the first phase, the second phase, the first amplitude, and the second amplitude.

37. The system of claim 32, wherein the radiator includes an antenna positioned substantially in a plane defined by a first direction and a second direction orthogonal to the first direction, the antenna being symmetric about a center in the first direction and in the second direction, the antenna including a first port positioned at an edge of the antenna in the first direction and a second port positioned at an edge of the antenna in the second direction.

38. The system of claim 32, wherein the radiator includes a first antenna adapted to radiate the first electromagnetic wave and second antenna adapted to radiate the second electromagnetic wave.

39. The system of claim 32, wherein the first polarization is a clock-wise circular polarization and the second polarization is a counter-clock-wise circular polarization.

40. The system of claim 32, wherein the first polarization is a first linear polarization having a first angle and the second polarization is a second linear polarization having a second angle substantially perpendicular to the first angle.

41. The system of claim 32, wherein the third polarization is a linear polarization.

42. The system of claim 32, wherein the third polarization is an elliptical polarization.

43. The system of claim 32, wherein a first phase of the first electromagnetic wave is equal to a second phase of the second electromagnetic wave, the first polarization is a clock-wise circular polarization, the second polarization is a counter-clock-wise circular polarization, wherein the one or more parts includes a first amplitude of the first electromagnetic wave and a second amplitude of the second electromagnetic wave, the third polarization being an elliptical polarization having a polarization ratio responsive to the data.

44. The system of claim 43, wherein the polarization ratio is a quotient of the first amplitude divided by the second amplitude.

45. The system of claim 43, wherein the polarization ratio corresponds to a symbol representing the data.

46. The system of claim 45, wherein the symbol sends a single bit of information at a time.

47. The system of claim 45, wherein the symbol sends a plurality of bits of data simultaneously in time.

48. A system for receiving a data from an electromagnetic wave by polarization demodulation comprising:

an antenna adapted to pick up a first signal having a first polarization and a second signal having a second polarization, the first and second signals being associated with the electromagnetic wave, the electromagnetic wave including a third polarization;

a first circuit adapted to determine an amplitude of the first signal;

a second circuit adapted to determine an amplitude of the second signal; and

a third circuit adapted to determine an angle of the third polarization responsive to the data.

49. The system of claim 48, wherein the first and second polarizations are linear.

50. The system of claim 49, wherein the first and second polarizations are substantially orthogonal.

51. The system of claim 48, wherein the third circuit is further adapted to calculate a quotient of the amplitude of the second signal divided by the amplitude of the first signal, wherein the quotient is responsive to the angle.