TRANSPOSITIONAL MODULATION SYSTEMS AND METHODS

• US 20160197751A1
• Filed: 03/03/2016
• Published: 07/07/2016
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: TM IP Holdings LLC
• Original Assignee: TM IP Holdings LLC
• Inventors: GERDES, RICHARD C.
• Granted Patent: US 9,787,510 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 2027/0051 Harmonic tracking
• CPC Class Codes: H04L 2027/0055 single phase
• CPC Class Codes: H04L 2027/0067 Phase error detectors
• CPC Class Codes: H04L 27/02 Amplitude-modulated carrier systems, e.g. using on-off keying; Single sideband or vestigial sideband modulation H04L27/32 takes precedence
• CPC Class Codes: H04L 27/10 Frequency-modulated carrier systems, i.e. using frequency-shift keying H04L27/32 takes precedence
• CPC Class Codes: H04L 27/122 using digital generation of carrier signals digital function generators G06F1/02, H04L17/10; generating pulses having stepped portions using digital techniques H03K4/026
• CPC Class Codes: H04L 27/14 Demodulator circuits; Receiver circuits
• CPC Class Codes: H04L 27/30 wherein each code element is represented by a combination of frequencies
• CPC Class Codes: H04L 27/32 Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
• CPC Class Codes: H04L 7/0331 with a digital phase-locked loop [PLL] processing binary samples, e.g. add/subtract logic for correction of receiver clock H04L7/0337 takes precedence

Abstract

Systems and methods for transpositional modulation and demodulation are provided. One such method for generating a signal includes the steps of providing a look-up table having a plurality of quarter-cycle waveforms, each of said quarter-cycle waveforms associated with a respective input level; receiving an input signal; and outputting quarter-cycle waveforms associated with levels of the received input signal. Systems for transpositional modulation are also provided. One such system for generating a signal includes a look-up table having a plurality of quarter-cycle waveforms. Each of the quarter-cycle waveforms are associated with a respective input level, and the look-up table is configured to receive an input signal, and output quarter-cycle waveforms associated with levels of the received input signal.

Claims

1. A method of generating a signal, comprising the steps of:

providing a look-up table having a plurality of quarter-cycle waveforms, each of said quarter-cycle waveforms associated with a respective input level;

receiving an input signal; and

outputting quarter-cycle waveforms associated with levels of the received input signal.

2. The method of claim 1, wherein the input levels comprise voltage amplitudes.

3. The method of claim 1, wherein the input signal is an N-bits wide signal and the look-up table contains 2^N unique quarter-cycle waveforms, each associated with a respective input level.

4. The method of claim 1, further comprising the step of:

receiving a carrier signal, wherein the output quarter-cycle waveforms have the same frequency as the carrier signal.

5. The method of claim 1, further comprising the step of:

assembling the output quarter-cycle waveforms into one continuous output signal, and optionally further comprising the step of;

frequency-shifting a third harmonic component of the output signal to the carrier signal frequency, wherein the third harmonic component preferably is frequency-shifted to the carrier signal frequency by generating a second harmonic and mixing the second and third harmonics.

6. A method for generating a modulated signal, comprising the steps of:

receiving an carrier signal;

receiving an input signal;

generating a third harmonic sideband based on the received signals; and

frequency-shifting the third harmonic sideband to the frequency of the received carrier signal.

7. A method of demodulating a signal, comprising the steps of:

filtering out all but the third harmonic component from the modulated signal; and

detecting the phase of the third harmonic component.

8. A method of demodulating a signal, comprising the steps of:

converting the modulated signal to a digital signal;

performing a fast Fourier transform on the digital signal.

9. A system for generating a signal, comprising:

a look-up table having a plurality of quarter-cycle waveforms, each of said quarter-cycle waveforms associated with a respective input level, wherein said look-up table is configured to receive an input signal, and output quarter-cycle waveforms associated with levels of the received input signal.

10. The system of claim 9, wherein the input levels comprise voltage amplitudes.

11. The system of claim 9, wherein the input signal is an N-bits wide signal and the look-up table contains 2^N unique quarter-cycle waveforms, each associated with a respective input level.

12. The system of claim 9, wherein the look-up table is further comprised to receive a carrier signal, and wherein the output quarter-cycle waveforms have the same frequency as the carrier signal.

13. The system of claim 9, further comprising:

(a) an analog gate for assembling the output quarter-cycle waveforms into one continuous output signal, and/or

(b) a frequency-shifting element for frequency-shifting a third harmonic component of the output signal to the carrier signal frequency, wherein the frequency-shifting element preferably comprises a mixer for mixing the third harmonic component with the second harmonic component.

14. A system for generating a modulated signal, comprising:

a processor configured to generate a third harmonic sideband based on a received carrier signal and a received input signal, and to frequency-shift the third harmonic sideband to the frequency of the received carrier signal.

15. A system for demodulating a signal, comprising:

a subtraction element for subtracting a fundamental carrier signal from a received modulated signal;

a fundamental notch filter for filtering out the fundamental carrier signal, thereby leaving only the third harmonic component from the modulated signal; and

a third harmonic phase detector for detecting the phase of the third harmonic component.

16. A system for demodulating a signal, comprising:

an analog to digital converter for converting the modulated signal to a digital signal; and

a processor configured to perform a fast Fourier transform on the digital signal.