SYSTEM AND METHOD FOR ARBITRARY PHASE AND AMPLITUDE MODULATION IN AN ANTENNA

• US 20100208844A1
• Filed: 03/17/2010
• Published: 08/19/2010
• Est. Priority Date: 11/25/2008
• Status: Active Grant

• Current Assignee: Altamira Technologies Corporation
• Original Assignee: Invertix
• Inventors: Law, Daniel A., Uhl, Brecken H., Hurtado, Arthur D.
• Granted Patent: US 8,411,794 B2
• Time in Patent Office: Days
• US Class Current: 375/308
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: H04L 27/20 Modulator circuits; Transmitter circuits

Abstract

A system and method for arbitrarily switching phase and amplitude at an antenna. A Direct Spatial Antenna Modulation (DSAM) system makes use of the spatial characteristics of a radiating antenna structure to directly alter a signal transmitted or received by the radiating structure. A data stream maps a carrier to different spatial points of excitation in the antenna structure, where each chosen configuration has different radiating characteristics including phase, amplitude, and polarization, which can be used represent data symbols. The spatial points of a radiating structure may be mapped directly to In-Phase and Quadrature components of the output using two spatial feedpoints and amplitude control to the feedpoints. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this Abstract.

Claims

1. A direct spatial antenna modulation (DSAM) system comprising:

a radiating structure comprising a plurality of spatial points of origination; and

a control system, wherein the control system is connected to the radiating structure via one or more input ports and is configured to respond to a baseband data signal to direct an unmodulated carrier signal to one or more spatial points of origination selected from the plurality of spatial points of origination via the one or more input ports, and

wherein the selection of the one or more spatial points of origination by the control system determines a modulation characteristic of a signal transmitted by the radiating structure.

2. The DSAM system of claim 1, wherein the modulation characteristic is selected from the group consisting of an instantaneous phase, an amplitude, and a polarization.

3. The DSAM system of claim 1, wherein a unique data symbol is associated with a particular configuration of the control system, and wherein in response to the presence of the unique data symbol in the baseband data signal, the control system directs the carrier signal to the one or more spatial points of origination selected from the plurality of spatial points of origination to transmit the particular unique data symbol.

4. The DSAM system of claim 1, wherein the signal transmitted by the radiating structure conforms to a modulation scheme that is selected from the group consisting of a quadrature phase shift keying (QPSK), binary phase shift keying (BPSK), M-Ary, and dual circular polarized QPSK.

5. The DSAM system of claim 1, wherein the control system comprises one or more switching devices and wherein the control system directs the unmodulated carrier signal to the one or more spatial points of origination selected from the plurality of spatial points of origination by controlling the state of the one or more switching devices in response to the baseband data signal.

6. The DSAM antenna of claim 5, wherein the control system further comprises one or more amplitude control devices, wherein the control system configures the one or more amplitude control devices to adjust the amplitude of the unmodulated carrier in response to the baseband data signal, and wherein the selection of the one or more spatial points of origination and the amplitude of the unmodulated carrier fed to the selected spatial points of origination determines a phase and amplitude of the transmitted signal.

7. The DSAM system of claim 1, wherein the radiating structure is selected from the group consisting of a rectangular microstrip patch antenna, a circular disc microstrip patch antenna, a quadrifilar helix antenna, a waveguide horn antenna, a crossed dipole antenna, a quadri-filar helix antenna, and a dual-arm sinuous antenna.

8. The DSAM system of claim 1,

wherein the control system comprises one or more switching devices and a processor,

wherein the processor is configured with software executable instructions to cause the control system to perform operations comprising:

identifying a binary sequence in the baseband data signal;

arranging the binary sequence as unique symbols comprising one or more bits, wherein a unique data symbol is associated with a particular configuration of the control system, and

in response to the presence of the unique data symbol in the baseband data signal, control the state of the one or more switching devices to direct the carrier signal to the one or more spatial points of origination selected from the plurality of spatial points of origination to transmit the particular unique data symbol.

9. The DSAM system of claim 8, wherein the processor is configured with software executable instructions to cause the control system to perform the further operation of applying fixed phase shifts to the unmodulated carrier when fed to the one or more selected spatial points of origination.

10. A method of modulating a signal in a radiating structure comprising:

a control system receiving an unmodulated carrier signal and a baseband data signal; and

the control system directing the unmodulated carrier signal to selected spatial points of origination of the radiating structure in response to the baseband data signal,

wherein the selection of the one or more spatial points of origination by the control system determines a modulation characteristic of a transmitted signal by the radiating structure.

11. The method of claim 10, wherein the modulation characteristic is selected from the group consisting of an instantaneous phase, an amplitude, and a polarization.

12. The method of claim 10, wherein a unique data symbol is associated with a particular configuration of the control system, and wherein the method further comprises:

the control system in response to the presence of the unique data symbol in the baseband data signal, directing the carrier signal to the one or more spatial points of origination selected from the plurality of spatial points of origination to transmit the particular unique data symbol.

13. The method of claim 10, wherein the signal transmitted by the radiating structure conforms to a modulation scheme that is selected from the group consisting of a quadrature phase shift keying (QPSK), binary phase shift keying (BPSK), M-Ary, and dual circular polarized QPSK.

14. The method of claim 10, wherein the control system comprises one or more switching devices and wherein the control system directing the unmodulated carrier signal to selected spatial points of origination of the radiating structure in response to the baseband data signal comprises the control system directing the unmodulated carrier signal to the one or more spatial points of origination selected from the plurality of spatial points of origination by controlling the state of the one or more switching devices in response to the baseband data signal.

15. The method of claim 14, wherein the control system further comprises one or more amplitude control devices, wherein the control system directing the unmodulated carrier signal to selected spatial points of origination of the radiating structure in response to the baseband data signal comprises the control system configuring the one or more amplitude control devices to adjust the amplitude of the unmodulated carrier in response to the baseband data signal, and wherein the selection of the one or more spatial points of origination and the amplitude of the unmodulated carrier fed to the selected spatial points of origination determines a phase and amplitude of the transmitted signal.

16. The method of claim 10, wherein the radiating structure is selected from the group consisting of a rectangular microstrip patch antenna, a circular disc microstrip patch antenna, a quadrifilar helix antenna, a waveguide horn antenna, a crossed dipole antenna, a quadri-filar helix antenna, and a dual-arm sinuous antenna.

17. The method of claim 10, wherein the control system comprises one or more switching devices and a processor and wherein the method further comprises:

the processor identifying a binary sequence in the baseband data signal;

the processor arranging the binary sequence as unique symbols comprising one or more bits, wherein a unique data symbol is associated with a particular configuration of the control system, and

the control system in response to the presence of the unique data symbol in the baseband data signal, directing the carrier signal to the one or more spatial points of origination selected from the plurality of spatial points of origination to transmit the particular unique data symbol by controlling the state of the one or more switching devices.

18. The method of claim 17 further comprising:

the processor causing the control system to apply fixed phase shifts to the unmodulated carrier when fed to the one or more selected spatial points of origination.