Circuitry with resistive input impedance for generating pulses from analog waveforms

• US 6,486,819 B2
• Filed: 03/13/2001
• Issued: 11/26/2002
• Est. Priority Date: 10/28/1999
• Status: Expired due to Fees

• Current Assignee: National University of Singapore
• Original Assignee: National University of Singapore
• Inventors: Liu, Jonathan Tun Nan, Yong, Siong Siew, Lye, Kin Mun, Joe, Jurianto
• Primary Examiner(s): JEAN PIERRE, PEGUY
• Application Number:
  US09/805,845
• Publication Number:
  US 20010010501A1
• Time in Patent Office: 623 Days
• Field of Search: 341/157, 341/133, 341/111, 330/284, 331/74, 318/798, 327/514
• US Class Current: 341/157
• CPC Class Codes: H03K 3/313 by the use, as active elements, of semiconductor devices with two electrodes, one or two potential barriers, and exhibiting a negative resistance characteristic
• CPC Class Codes: H03K 3/315 the devices being tunnel diodes
• CPC Class Codes: H04B 1/71637 Receiver aspects H04B1/7183 takes precedence
• CPC Class Codes: H04B 1/7174 Pulse generation in general H04L25/03834
• CPC Class Codes: H04B 1/7176 Data mapping, e.g. modulation
• CPC Class Codes: H04L 1/22 using redundant apparatus to increase reliability
• CPC Class Codes: H04L 25/4906 using binary codes

Abstract

A decoder for generating output pulses or oscillations in response to input analog waveforms includes a circuit having a variable operating point and having a transfer function characterized by an unstable operating region bounded by a first stable operating region and a second stable operating region. In one embodiment, the circuit is characterized by having a resistive input impedance. The analog waveform forces the operating point of the circuit into its unstable and stable regions to produce oscillatory and non-oscillatory behavior at the circuit'"'"'s output.

Claims

1. A decoding system for generating pulses from analog waveforms comprising:

a source of a known but arbitrary analog waveform, each said analog waveform having a first information region and a second information region; and

a circuit with a variable operating point and having a transfer function characterized by an unstable operating region bounded by a first stable operating region and a second stable operating region,

said circuit having a resistive input impedance,

said circuit being responsive to sensing of said first information region to force said variable operating point to vary in order to initiate operation of said circuit in said unstable operating region to produce at least one oscillation, said oscillation having a frequency greater than rate of change of said operating point,

said circuit being further responsive to sensing of said second information region to force said variable operating point to vary into either one of said stable operating regions in order to terminate said at least one oscillation substantially without transients, wherein said initiating and said terminating alternate.

2. The system according to claim 1, wherein said analog waveform is cyclical.

3. The system of claim 1, wherein said analog waveform is selected from the group consisting of sinusoidal, ramp, asymmetric, sawtooth, square and channel-optimized symbol.

4. The system according to claim 1, wherein said analog waveform is cyclical and wherein said cycles comprise mixtures of different waveform types, including time-varying channel-optimized symbols.

5. The system according to claim 1 wherein said at least one oscillation has a peak to peak amplitude of at least zero to a maximum relative to non-oscillation.

6. The system according to claim 1 wherein said circuit includes a negative impedance element, wherein said unstable operating region is a negative impedance region, and wherein said operating point is forced into said unstable region by a time varying input signal.

7. The system according to claim 1 wherein said circuit includes an operational amplifier circuit with feedback, and having series input through a resistive element, wherein said unstable operating region is a negative resistance region, and wherein said operating point is forced into said unstable region by a changing voltage applied to said capacitor.

8. The system according to claim 1 wherein said analog signal originates from a transmitted signal.

9. A decoder for generating pulses from analog waveforms comprising:

a first circuit for producing a known but arbitrary analog waveform, each said analog waveform having a first information region and a second information region; and

a second circuit having at least one input and an output,

said second circuit further having a feedback path comprising a reactive element coupled between said output said at least one input,

said second circuit having a variable operating point,

said second circuit further having a transfer function characterized by an unstable operating region bounded by a first stable operating region and a second stable operating region,

said second circuit being responsive to sensing of said first information region to force said variable operating point to vary in order to initiate operation of said circuit in said unstable operating region to produce at least one oscillation, said oscillation having a frequency greater than rate of change of said operating point,

said circuit being further responsive to sensing of said second information region to force said variable operating point to vary into either one of said stable operating regions in order to terminate said at least one oscillation substantially without transients,

wherein said initiating and said terminating alternate.

10. The decoder according to claim 9 wherein said reactive element is a capacitor.

11. The decoder according to claim 9 wherein said reactive element is an inductor.

12. The decoder according to claim 9, wherein said analog waveform is cyclical.

13. The decoder of claim 9, wherein said analog waveform is selected from the group consisting of sinusoidal, ramp, asymmetric, sawtooth, square and channel-optimized symbol.

14. The decoder according to claim 9, wherein said analog waveform is cyclical and wherein said cycles comprise mixtures of different waveform types, including time-varying channel-optimized symbols.

15. The decoder according to claim 9 wherein said at least one oscillation has a peak to peak amplitude of at least zero to a maximum relative to non-oscillation.

16. The decoder according to claim 9 wherein said circuit includes a negative impedance element, wherein said unstable operating region is a negative impedance region, and wherein said operating point is forced into said unstable region by a time varying input signal.