Information Transfer Using Discrete-Frequency Signals and Instantaneous Frequency Measurement

Abstract

A method of receiving information is provided. The method, performed at a system for information transfer, includes receiving a signal pulse and determining a frequency band and a pulse duration associated with the signal pulse. The method includes, in accordance with a determination that the frequency band is one of a set of frequency bands, determining, from a first set of symbols, a first symbol associated with the frequency band. The method also includes, in accordance with a determination that the pulse duration is one of a set of pulse durations, determining, from a distinct second set of symbols, a second symbol associated with the pulse duration. Each frequency band in the set of frequency bands is associated with a respective symbol in the first set of symbols, and each pulse duration in the set of pulse durations is associated with a respective symbol in the second set of symbols.

What is claimed is: 
     
         1 . A method of receiving information, comprising:
 receiving a first signal pulse;   determining a first frequency band associated with the first signal pulse;   determining a first pulse duration of the first signal pulse;   in accordance with a determination that the first frequency band is a first respective frequency band in a first predefined set of frequency bands:
 determining, from a first predefined set of symbols, a first symbol associated with the first frequency band and represented by the first signal pulse; and 
   in accordance with a determination that the first pulse duration is a first respective pulse duration in a first predefined set of pulse durations:
 determining, from a second predefined set of symbols that is distinct from the first predefined set of symbols, a second symbol associated with the first pulse duration and represented by the first signal pulse; 
   wherein:
 each frequency band in the first predefined set of frequency bands is associated with a distinct respective symbol in the first predefined set of symbols; and 
 each pulse duration in the first predefined set of pulse durations is associated with a distinct respective symbol in the second predefined set of symbols. 
   
     
     
         2 . The method of  claim 1 , wherein each symbol in the first predefined set of symbols is associated with only one respective frequency band in the first predefined set of frequency bands, and each symbol in the second predefined set of symbols is associated with only one respective pulse duration in the first predefined set of pulse durations. 
     
     
         3 . The method of  claim 1 , including:
 in accordance with the determination that the first frequency band is a first respective frequency band in a first predefined set of frequency bands:
 after determining the first symbol associated with the first frequency band and represented by the first signal pulse, providing the first symbol; and 
   in accordance with the determination that the first pulse duration is a first respective pulse duration in a first predefined set of pulse durations:
 after determining the second symbol associated with the first pulse duration and represented by the first signal pulse, providing the second symbol. 
   
     
     
         4 . The method of  claim 1 , including:
 after at least a predefined amount of time since receiving the first signal pulse, receiving a second signal pulse;   determining a second frequency band associated with the second signal pulse, wherein the second frequency band is the same as the first frequency band;   determining a second pulse duration of the second signal pulse, wherein the second pulse duration is distinct from the first pulse duration; and   in accordance with a determination that the second frequency band is the first respective frequency band in the first predefined set of frequency bands:
 providing the first symbol; and 
   in accordance with a determination that the second pulse duration is a second respective pulse duration in the first predefined set of pulse durations:
 determining, from the second predefined set of symbols, a third symbol associated with the second pulse duration and represented by the second signal pulse, wherein the third symbol is distinct from the second symbol. 
   
     
     
         5 . The method of  claim 1 , including:
 after at least a predefined amount of time since receiving the first signal pulse, receiving a third signal pulse;   determining a third frequency band associated with the third signal pulse, wherein the third frequency band is distinct from the first frequency band;   determining a third pulse duration of the third signal pulse, wherein the third pulse duration is the same as the first pulse duration; and   in accordance with a determination that the third frequency band is a second respective frequency band in the first predefined set of frequency bands:
 determining, from the first predefined set of symbols, a fourth symbol associated with the third frequency band and represented by the third signal pulse, wherein the fourth symbol is distinct from the first symbol; and 
   in accordance with a determination that the third pulse duration is the first respective pulse duration in the first predefined set of pulse durations:
 providing the second symbol. 
   
     
     
         6 . The method of  claim 1 , wherein the frequency bands in the first predefined set of frequency bands, in aggregate, are not contiguous. 
     
     
         7 . The method of  claim 1 , wherein:
 the first predefined set of frequency bands and the first predefined set of pulse durations are associated with the first predefined set of symbols and the second predefined set of symbols using one or more lookup tables;   determining the first symbol associated with the first frequency band includes:
 selecting the respective symbol in the first predefined set of symbols that is associated with the first frequency band in the one or more lookup tables; and 
   determining the second symbol associated with the first pulse duration includes:
 selecting the respective symbol in the second predefined set of symbols that is associated with the first pulse duration in the one or more lookup tables. 
   
     
     
         8 . The method of  claim 1 , including, after receiving the first signal pulse:
 receiving a control signal associating a second predefined set of frequency bands with the first predefined set of symbols, wherein:
 the second predefined set of frequency bands is distinct from the first predefined set of frequency bands; and 
 each frequency band in the second predefined set of frequency bands is associated with a distinct respective symbol in the first predefined set of symbols; 
   after receiving the control signal, receiving a fourth signal pulse;   determining a fourth frequency band associated with the fourth signal pulse;   determining a fourth pulse duration of the fourth signal pulse;   in accordance with a determination that the fourth frequency band is a respective frequency band in the second predefined set of frequency bands:
 determining, from the first predefined set of symbols, a respective symbol associated with the fourth frequency band and represented by the fourth signal pulse; and 
   in accordance with a determination that the fourth pulse duration is a respective pulse duration in the first predefined set of pulse durations:
 determining, from the second predefined set of symbols, a respective symbol associated with the fourth pulse duration and represented by the fourth signal pulse. 
   
     
     
         9 . A system for information transfer, comprising:
 a receiver, configured to receive a first signal pulse;   frequency determination circuitry, configured to determine a first frequency band associated with the first signal pulse;   pulse duration determination circuitry, configured to determine a first pulse duration of the first signal pulse; and   processing circuitry, configured to:
 in accordance with a determination that the first frequency band is a first respective frequency band in a first predefined set of frequency bands:
 determine, from a first predefined set of symbols, a first symbol associated with the first frequency band and represented by the first signal pulse; and 
 
 in accordance with a determination that the first pulse duration is a first respective pulse duration in a first predefined set of pulse durations:
 determine, from a second predefined set of symbols that is distinct from the first predefined set of symbols, a second symbol associated with the first pulse duration and represented by the first signal pulse; 
 
   wherein:
 each frequency band in the first predefined set of frequency bands is associated with a distinct respective symbol in the first predefined set of symbols; and 
 each pulse duration in the first predefined set of pulse durations is associated with a distinct respective symbol in the second predefined set of symbols. 
   
     
     
         10 . A method of transmitting information, comprising:
 obtaining a first symbol, in a first predefined set of symbols, for transmission;   obtaining a second symbol, in a second predefined set of symbols, for transmission;   determining a first frequency band, in a first predefined set of frequency bands, associated with the first symbol;   determining a first pulse duration, in a first predefined set of pulse durations, associated with the second symbol; and   transmitting a first signal pulse having the first pulse duration and having a first frequency in the first frequency band, wherein the first signal pulse represents the first symbol and the second symbol;   wherein:
 each frequency band in the first predefined set of frequency bands is associated with a distinct respective symbol in the first predefined set of symbols; and 
 each pulse duration in the first predefined set of pulse durations is associated with a distinct respective symbol in the second predefined set of symbols. 
   
     
     
         11 . The method of  claim 10 , wherein each symbol in the first predefined set of symbols is associated with only one respective frequency band in the first predefined set of frequency bands, and each symbol in the second predefined set of symbols is associated with only one respective pulse duration in the first predefined set of pulse durations. 
     
     
         12 . The method of  claim 10 , further comprising:
 obtaining a third symbol, in the first predefined set of symbols, for transmission, wherein the third symbol is the same as the first symbol;   obtaining a fourth symbol, in the second predefined set of symbols, for transmission, wherein the fourth symbol is distinct from the second symbol;   determining a second frequency band, in the first predefined set of frequency bands, associated with the third symbol, wherein the second frequency band is the same as the first frequency band;   determining a second pulse duration, in the first predefined set of pulse durations, associated with the fourth symbol, wherein the second pulse duration is distinct from the first pulse duration; and   after at least a predefined amount of time since transmitting the first signal pulse, transmitting a second signal pulse having the second pulse duration and having a respective frequency in the first frequency band.   
     
     
         13 . The method of  claim 10 , further comprising:
 obtaining a fifth symbol, in the first predefined set of symbols, for transmission, wherein the fifth symbol is distinct from the first symbol;   obtaining a sixth symbol, in the second predefined set of symbols, for transmission, wherein the sixth symbol is the same as the second symbol;   determining a third frequency band, in the first predefined set of frequency bands, associated with the fifth symbol, wherein the third frequency band is distinct from the first frequency band;   determining a third pulse duration, in the first predefined set of pulse durations, associated with the sixth symbol, wherein the third pulse duration is the same as the first pulse duration; and   after at least a predefined amount of time since transmitting the first signal pulse, transmitting a third signal pulse having the first pulse duration and having a respective frequency in the third frequency band.   
     
     
         14 . The method of  claim 10 , wherein the frequency bands in the first predefined set of frequency bands, in aggregate, are not contiguous. 
     
     
         15 . The method of  claim 10 , wherein:
 the first predefined set of frequency bands and the first predefined set of pulse durations are associated with the first predefined set of symbols and the second predefined set of symbols using one or more lookup tables;   determining the first frequency band associated with the first symbol includes:
 selecting the respective frequency band in the first predefined set of frequency bands that is associated with the first symbol in the one or more lookup tables; and 
   determining the first pulse duration associated with the second symbol includes:
 selecting the respective pulse duration in the first predefined set of pulse durations that is associated with the second symbol in the one or more lookup tables. 
   
     
     
         16 . The method of  claim 10 , including, after transmitting the first signal pulse:
 transmitting a control signal associating a second predefined set of frequency bands with the first predefined set of symbols, wherein:
 the second predefined set of frequency bands is distinct from the first predefined set of frequency bands; and 
 each frequency band in the second predefined set of frequency bands is associated with a distinct respective symbol in the first predefined set of symbols; 
   after transmitting the control signal:
 obtaining a first respective symbol, from the first predefined set of symbols, for transmission; 
 obtaining a second respective symbol, from the second predefined set of symbols, for transmission; 
 determining a fourth frequency band, in the second predefined set of frequency bands, associated with the first respective symbol; 
 determining a fourth pulse duration, in the first predefined set of pulse durations, associated with the second respective symbol; and 
 after at least a predefined amount of time since transmitting the first signal pulse, transmitting a fourth signal pulse having the fourth pulse duration and having a respective frequency in the fourth frequency band. 
   
     
     
         17 . A system for information transfer, comprising:
 processing circuitry, configured to:
 obtain a first symbol, in a first predefined set of symbols, for transmission; 
 obtain a second symbol, in a second predefined set of symbols, for transmission; 
 determine a first frequency band, in a first predefined set of frequency bands, associated with the first symbol; and 
 determine a first pulse duration, in a first predefined set of pulse durations, associated with the second symbol; and 
   a transmitter, configured to transmit a first signal pulse having the first pulse duration and having a first frequency in the first frequency band, wherein the first signal pulse represents the first symbol and the second symbol;   wherein:
 each frequency band in the first predefined set of frequency bands is associated with a distinct respective symbol in the first predefined set of symbols; and 
 each pulse duration in the first predefined set of pulse durations is associated with a distinct respective symbol in the second predefined set of symbols.