Ultra wideband data transmission system and method

• US 6,690,741 B1
• Filed: 11/22/1999
• Issued: 02/10/2004
• Est. Priority Date: 05/16/1997
• Status: Expired due to Term

• Current Assignee: Zebra Technologies Corporation
• Original Assignee: Multispectral Solutions Incorporated (Zebra Technologies Corporation)
• Inventors: Larrick, J. Frederick Jr., Fontana, Robert J.
• Primary Examiner(s): Fan, Chieh M.
• Application Number:
  US09/447,343
• Time in Patent Office: 1,541 Days
• Field of Search: 375/130, 375/219, 375/256, 375/295, 375/316, 375/261, 375/268, 375/271, 375/272, 375/279, 375/298, 375/300, 375/302, 375/303, 375/308, 342/13, 342/21, 342/27, 342/28, 342/159, 342/375
• US Class Current: 375/295
• CPC Class Codes: H04B 1/7174 Pulse generation in general H04L25/03834
• CPC Class Codes: H04B 2001/6908 using time hopping
• CPC Class Codes: H04L 27/04 Modulator circuits; Transmitter circuits

Abstract

A data-modulated ultra wideband transmitter that modulates the phase, frequency, bandwidth, amplitude and/or attenuation of ultra-wideband (UWB) pulses. The transmitter confines or band-limits UWB signals within spectral limits for use in communication, positioning, and/or radar applications. One embodiment comprises a low-level UWB source (e.g., an impulse generator or time-gated oscillator (fixed or voltage-controlled)), a waveform adapter (e.g., digital or analog filter, pulse shaper, and/or voltage variable attenuator), a power amplifier, and an antenna to radiate a band-limited and/or modulated UWB or wideband signals. In a special case where the oscillator has zero frequency and outputs a DC bias, a low-level impulse generator impulse-excites a bandpass filter to produce an UWB signal having an adjustable center frequency and desired bandwidth based on a characteristic of the filter. In another embodiment, a low-level impulse signal is approximated by a time-gated continuous-wave oscillator to produce an extremely wide bandwidth pulse with deterministic center frequency and bandwidth characteristics. The UWB signal may be modulated to carry multi-megabit per second digital data, or may be used in object detection or for ranging applications. Activation of the power amplifier may be time-gated in cadence with the UWB source thereby to reduce inter-pulse power consumption. The UWB transmitter is capable of extremely high pulse repetition frequencies (PRFs) and data rates in the hundreds of megabits per second or more, frequency agility on a pulse-to-pulse basis allowing frequency hopping if desired, and extensibility from below HF to millimeter wave frequencies.

Claims

1. A method of producing band-limited ultra-wideband data transmissions comprising a series of UWB data signals representing digital data, said method comprising:

generating a series of low-level impulse-switched ultra-wideband pulses of a given amplitude;

filtering said low-level ultra wideband pulses to produce an UWB signal confined to a band-limited spectral range;

modulating the amplitude of said UWB signal according to digital data thereby to produce an amplitude-modulated UWB data signal; and

supplying said amplitude-modulated UWB data signal to an antenna.

2. The method as recited in claim 1 further including the step of amplifying said amplitude-modulated UWB data signal before said supplying step.

3. A method of producing ultra-wideband data transmissions comprising a series of UWB signals representing digital data, said method comprising:

generating a series of low-level impulse-switched ultra-wideband pulses;

waveform adapting said low-level impulse-switched ultra wideband pulses to produce an UWB signal confined to a spectral range;

modulating said low-level impulse-switched UWB signal confined to said spectral range according to digital data thereby to produce a data-bearing UWB signal; and

supplying said data-bearing UWB signal to an antenna.

4. The method as recited in claim 3 further including the step of amplifying said data-bearing UWB signal before said supplying step.

5. A method of producing band-limited ultra-wideband data transmissions comprising a series of UWB data signals representing digital data, said method comprising:

phase-modulating an oscillating signal source to produce a phase-modulated signal,

generating a series of low-level impulse-switched ultra-wideband pulses from said phase-modulated signal;

filtering said impulse-switched ultra wideband pulses to produce an UWB signal having a frequency confined within a band-limited spectral range; and

supplying said UWB signal to an antenna whereby to produce said band-limited ultra-wideband data transmissions.

6. The method as recited in claim 5 further including the step of amplifying said UWB signal before said supplying step.

7. A method of producing QAM-modulated UWB data signals representing digital data, said method comprising:

providing a microwave oscillator to generated a low-level signal;

time-gating said low-level signal within a several nanosecond to sub-nanosecond interval to generate a time-gated UWB signal output;

modulating said oscillator in phase and modulating said time-gated UWB signal output in amplitude according to digital data thereby to generate a data-modulated output; and

supplying said data-modulated output to an antenna thereby to radiate QAM-modulated UWB data signals representing digital data.

8. The method as recited in claim 7, further comprising amplifying said data-modulated output before the supplying step.

9. A method of producing PSK-modulated UWB data signals representative of digital data, said method comprising:

providing a microwave oscillator to generated a low-level signal;

PSK-modulating said low-level signal according to digital data thereby to generate a phase-modulated output;

time-gating said phase-modulated output within a several nanosecond to sub-nanosecond interval to generate an UWB signal output; and

supplying said modulated output to an antenna whereby to radiate PSK-modulated UWB data signals representative of digital data.

10. The method as recited in claim 9, further comprising the step of amplifying said UWB signal output before said supplying step.

11. A method of producing M-ary modulated UWB data signals representative of digital data, said method comprising:

providing a microwave oscillator to generate a low-level signal having a defined center-frequency;

time-gating said low-level signal to produce a gated output of several nanoseconds to a sub-nanosecond duration, said gated output having a center-frequency corresponding to a frequency of said oscillator;

modulating said oscillator in at least one of phase and frequency and modulating said gated output in multi-level amplitudes according to digital data thereby to generate a modulated output; and

supplying said modulated output to an antenna.

12. The method as recited in claim 11, further comprising the step of amplifying said modulated output prior to said supplying step.

13. A method of producing M-ary modulated UWB data signals representative of digital data, said method comprising:

providing a voltage-controlled oscillator that generates a low-level millimeter wave signal having a frequency;

time-gating said millimeter wave signal to produce a gated output of several nanoseconds to a sub-nanosecond duration;

controlling the frequency of said voltage-controlled oscillator according to digital data thereby to produce a time-gated, frequency-modulated UWB data signal; and

supplying said time-gated, frequency-modulated UWB data signal to an antenna.

14. The method as recited in claim 13, further comprising the step of amplifying said time-gated, frequency-modulated UWB data signal prior to said supplying step.

15. A band-limited, ultra-wideband data transmission system that transmits a series of UWB signals representing digital data, said system comprising:

a switched impulse generator to generate a series of low-level ultra wideband signals;

a filter that band-limits said low-level ultra wideband signals to produce a series of millimeter wave signals each having multiple cycles confined within a given spectral range;

a data modulator that modulates the amplitude of said millimeter wave signals according to digital data; and

an antenna responsive to said data modulator to radiate UWB signals representative of digital data.

16. The band-limited ultra wideband transmission system as recited in claim 15, further including an amplifier to amplify said modulated millimeter wave signals.

17. A phase-modulated ultra-wideband data transmission system for transmitting a series of signals representing digital data, said system comprising:

a switched impulse generator to generate a series of low-level ultra-wideband signals;

a filter that band-limits said low-level ultra wideband signals to produce a series of millimeter wave signals each having multiple cycles confined within a given spectral range;

a modulator that modulates the phase of said series of millimeter wave signals according to digital data; and

an antenna responsive to said modulator to radiate signals representative of digital data.

18. The phase-modulated ultra wideband transmission system as recited in claim 17, further including an amplifier responsive to said modulator.

19. An UWB data transmission system that transmits a series of UWB signals representing digital data, said system comprising:

a switched impulse generator to generate a series of low-level ultra wideband signals;

a waveform adapter that waveform adapts said low-level ultra wideband signals to produce a series of millimeter wave signals each having multiple cycles confined within a given spectral range, said waveform adapter controlling at least one of center-frequency, amplitude, and phase of said millimeter wave signals according to digital data; and

an antenna responsive to said data modulator to radiate UWB signals representative of digital data.

20. The UWB data transmission system as recited in claim 19, further comprising an amplifier responsive to said waveform adapter.

21. An UWB data transmission system that transmits a series of UWB signals representing digital data, said system comprising:

a switched impulse generator to generate a series of low-level ultra wideband signals;

a waveform adapter that band-limits said low-level ultra wideband signals to produce a series of millimeter wave signals each having multiple cycles confined within a given spectral range;

a data modulator that modulates said millimeter wave signals according to digital data; and

an antenna responsive to said data modulator to radiate UWB signals representing digital data.

22. The UWB data transmission system as recited in claim 21, further comprising an amplifier responsive to said data modulator.

23. A QAM-modulated UWB data transmission system that transmits a series of signals representative of digital data, said system comprising:

a microwave oscillator to generated a low-level signal;

a time gate that produces a several nanosecond to sub-nanosecond output of said oscillator;

a data modulator that modulates the oscillator in at least one of phase and center-frequency, and that modulates the output of said time gate in amplitude;

an amplifier responsive to said data modulator to produce an amplified output; and

an antenna responsive to said amplified output to radiate signals representative of digital data.

24. A PSK-modulated UWB data transmission system that transmits a series of signals representative of digital data, said system comprising:

a microwave oscillator to generated a low-level signal;

a phase-modulating source applied to said microwave oscillator to PSK-modulate said low-level signal according to digital data thereby to produce a PSK-modulated low level signal;

a time gate that gates a several nanosecond to sub-nanosecond output from said PSK-modulated low-level signal;

an amplifier responsive to said PSK-modulated low-level signal to produce an amplified output; and

an antenna responsive to said amplified output to radiate PSK-modulated UWB signals representative of digital data.

25. An M-ary modulated UWB signal transmitter that transmits a series of short data-bearing signals representative of digital data, said transmitter comprising:

a microwave oscillator to generate a low-level signal;

a time gate that gates a several nanosecond to sub-nanosecond output of said oscillator to produce a signal having at least one of a phase, amplitude, bandwidth, and center-frequency;

a data modulator that modulates said oscillator in at least one of phase and center-frequency and that modulates the output of said time gate in amplitude according to digital data;

an amplifier responsive to said data-modulator to produce an amplified output; and

an antenna responsive to said amplified output to radiate M-ary modulated UWB signals.