Transpositional modulation systems and methods

• US 9,379,925 B2
• Filed: 03/25/2015
• Issued: 06/28/2016
• 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.
• Primary Examiner(s): Ghulamali, Qutbuddin
• Application Number:
  US14/668,536
• Publication Number:
  US 20150200796A1
• Time in Patent Office: 461 Days
• Field of Search: 375/269, 375/273, 375/277, 375/276, 375280-281, 375/286, 375/268, 375/303
• 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 demodulating a signal, comprising the steps of:

adding a third harmonic to a modulated signal;

detecting a peak amplitude of the modulated signal and the third harmonic;

generating, by a reference ramp generator, a reference ramp when the peak amplitude is detected;

detecting an inflection in the modulated signal and the third harmonic;

sampling the reference ramp when the inflection is detected to produce a sampled value; and

holding and outputting the sampled value.

2. The method of claim 1, wherein the third harmonic is generated by a phase-locked loop.

3. A system for demodulating a signal, comprising:

a signal adder for adding a third harmonic to a modulated signal;

a peak detector for detecting a peak amplitude of the modulated signal and the third harmonic;

a reference ramp generator for generating a reference ramp when the peak amplitude is detected;

an inflection detector for detecting an inflection in the modulated signal and the third harmonic;

a sample and hold element for sampling the reference ramp when the inflection is detected to produce a sampled value; and

hold and output the sampled value.

4. The system of claim 3, further comprising a phase-locked loop for generating the third harmonic.