초록 ▼

Harmonic techniques are employed to leverage low-cost, ordinary surface mount technology (SMT) to high microwave frequencies where tight beamforming with a small antenna makes reliable, high-accuracy pulse-echo radar systems possible. The implementation comprises a 24 GHz short-pulse transceiver com

Harmonic techniques are employed to leverage low-cost, ordinary surface mount technology (SMT) to high microwave frequencies where tight beamforming with a small antenna makes reliable, high-accuracy pulse-echo radar systems possible. The implementation comprises a 24 GHz short-pulse transceiver comprised of a pulsed harmonic oscillator employed as a transmitter and an integrating, pulsed harmonic sampler employed as a receiver. The transmit oscillator generates a very short (0.5 ns) phase-coherent harmonic-rich oscillation at a sub-multiple of the actual transmitter frequency. A receiver local oscillator operates at a sub-multiple of the transmit frequency and is triggered with controlled timing to provide a very short (0.5 ns), phase-coherent local oscillator burst. The local oscillator burst is coupled to an integrating harmonic sampler to produce an integrated, equivalent-time replica of the received RF. The harmonic techniques overcome four major problems with non-harmonic approaches: 1) expensive, precision assembly, 2) high local oscillator noise, 3) sluggish oscillator startup, and 4) spurious local oscillator injection locking on external RF. The transceiver can be used for automotive backup and collision warning, precision radar rangefinding for fluid level sensing and robotics, precision radiolocation, wideband communications, and time-resolved holographic imaging.

대표청구항 ▼

[ What is claimed is:] [1.] A short pulse microwave transceiver apparatus comprising:a transmit clock for generating a transmit clock signal;a pulsed transmit oscillator for producing transmitter RF bursts in response to the transmit clock signal;a transmit antenna connected to the transmit oscillat

[ What is claimed is:] [1.] A short pulse microwave transceiver apparatus comprising:a transmit clock for generating a transmit clock signal;a pulsed transmit oscillator for producing transmitter RF bursts in response to the transmit clock signal;a transmit antenna connected to the transmit oscillator to transmit the transmitter RF bursts;a receive clock for generating a receive clock signal;a pulsed local oscillator for generating gating RF bursts in response to the receive clock signal;a harmonic sampler connected to the pulsed local oscillator;a receive antenna connected to the harmonic sampler to receive RF bursts;wherein the gating RF bursts from the pulsed local oscillator gate the harmonic sampler to detect RF bursts received by a receive antenna;circuitry responsive to the harmonic sampler to provide a detected baseband output.