Multispectral Solutions, Inc.

J Frederick Larrick, Jr

Robert J Fontana

A waveform-adaptive ultra-wideband (UWB) transmitter and noise-tracking UWB receiver for use in communications, object detection and radar applications. In one embodiment, the output of an oscillator is gated by a low-level impulse generator either directly or through an optional filter. In a special case of that embodiment wherein the oscillator is 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, the 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 low-level impulse signal can be generated digitally. The UWB signal may be modulated to carry data, or may be used in object detection or ranging applications. The power amplifier may be gated to provide a power-efficient UWB transmitter. The UWB transmitter exhibits well defined and controllable spectral characteristics. 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.

Ultra-wideband receiver and transmitter

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.

Ultra wideband data transmission system and method

A waveform adaptive transmitter that conditions and/or 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.

Waveform adaptive ultra-wideband transmitter

An UWB receiver utilizing a microwave tunnel diode as a single pulse detector for short pulse, impulse, baseband or ultra wideband signals. The tunnel diode detector's bias point is set at system start-up, through an automatic calibration procedure to its highest sensitivity point relative to the desired bit error rate performance (based upon internal noise only) and remains there during the entire reception process. High noise immunity is achieved through the use of a high speed, adaptive dynamic range extension process using a high speed, Gallium Arsenide (GaAs) voltage variable attenuator (VVA) whose instantaneous attenuation level is determined by a periodic sampling of the ambient noise environment. Microprocessor-controlled detector time-gating is performed to switch the tunnel diode detector to the receiver front end circuitry for reception of an incoming UWB pulse, and alternately to ground through a resistor to discharge stored charge on the tunnel diode detector. In a second embodiment, two tunnel diode detectors are utilized in parallel, one biased for data detection and the other biased for noise detection, such that data detection can be interpreted based on simultaneous comparison to both a data threshold and a noise threshold.

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Silver Spring, MD, United States of America

J Frederick Larrick, Jr