Dual-frequency, remote ocean-wave spectrometer

Claim 2

An ocean-wave spectrometer radar system comprising: transmitter means, having closely spaced, coherently related, dual-frequency channels, for generating a first local-oscillator frequency and for transmitting a pair of closely spaced microwave frequencies: coherent receiver means for receiving and separating the radar returns of said transmitter dual-frequency channels; frequency-shifter means connected to said transmitter means and said receiver means for shifting the frequency of said first local-oscillator frequency; and multiplier means receiving said separated radar returns from said receiver and multiplying said separated radar returns to obtain a Bragg resonance condition.

Claim 3

The system of claim 1 including a precorrelation filter connected between said coherent receiver means and said multiplier means for passing a narrow band of doppler-shifted radar returns from capillaries bunched near gravity-wave crests.

Claim 4

The radar system of claim 2, including spectrum analyzer means receiving the output of said multiplier for Fourier-transforming and averaging said multiplier output to produce a power spectrum.

Claim 5

An ocean-wave spectrometer radar system comprising: trnasmitter means, having closely spaced, coherently related, dual-frequency, transmitter channels and including a microwave signal generator, for transmitting a pair of closely spaced microwave frequencies and generating a first local-oscillator frequency; coherent receiver means, including phase-matching circuitry, for receiving and separating radar returns from said transmitter dual-frequency channels; frequency shifter means connected to said microwave signal generator and said phase-matching circuitry, for shifting the frequency of said first local-oscillator frequency; and multiplier means for receiving said separated radar returns from said receiver and multiplying said separated radar returns.

Claim 6

An ocean-wave spectrometer radar system comprising: trnasmitter means, having closely spaced, coherently related, dual-frequency, transmitter channels and including a microwave signal generator, for transmitting a pair of closely spaced microwave frequencies and generating a first local-oscillator frequency; coherent receiver means, including phase-matching circuitry, for receiving and separating radar returns from said transmitter dual-frequency channels; frequency shifter means connected to said microwave signal generator and said phase-matching circuitry, for shifting the frequency of said first local-oscillator frequency; and multiplier means for receiving said separated radar returns from said receiver and multiplying said separated radar returns.

Claim 7

The system of claim 4, including a precorrelation filter connected between said phase-matching circuitry and said multiplier for passing a narrow band of doppler-shifted radar returns from capillaries bunched near gravity-wave crests.

Claim 8

The radar system of claim 5, including spectrum analyzer means for receiving the output of said multiplier for averaging and Fourier-transforming said multiplier output to produce a power spectrum.

Claim 9

An ocean-wave spectrometer radar system comprising: transmitter means, having closely and variably spaced, coherently related, dual-transmitter channels and including a microwave signal generator, for transmitting a pair of closely and variably spaced microwave frequencies and generating a first local-oscillator frequency; coherent receiver means, including phase-matching circuitry, for receiving and separating radar returns from said transmitted dual-frequency channels; frequency shifter means connected to said microwave signal generator and said phase-matching circuitry for shifting the frequency of said first local-oscillator frequency; and multiplier means for receiving said separated radar returns from said receiver and multiplying said separated radar returns.

Claim 10

An ocean-wave spectrometer radar system comprising: transmitter means, having closely and variably spaced, coherently related, dual-transmitter channels and including a microwave signal generator, for transmitting a pair of closely and variably spaced microwave frequencies and generating a first local-oscillator frequency; coherent receiver means, including phase-matching circuitry, for receiving and separating radar returns from said transmitted dual-frequency channels; frequency shifter means connected to said microwave signal generator and said phase-matching circuitry for shifting the frequency of said first local-oscillator frequency; and multiplier means for receiving said separated radar returns from said receiver and multiplying said separated radar returns.

Claim 11

The system of claim 7, including a precorrelation filter connected between said phase-matching circuitry and said multiplier for passing a narrow band of doppler-shifted radar returns from capillaries bunched near gravity-wave crests.

Claim 12

The system of claim 8, in which said precorrelation filter includes a pair of bandpass filters each receiving a different one of the separated radar returns from said phase-matching circuitry.

Claim 13

The system of claim 9, in which said transmitter includes: modulator means for generating a variable modulating frequency; double balanced mixer means, receiving the output of said microwave frequency generator and said modulating frequency, for generating a pair of variably and closely spaced transmitter frequencies and suppressing said microwave frequency.

Claim 14

The system of claim 10, in which said phase-matching circuitry includes: single sideband generator means receiving said radar returns and said first local oscillator frequency, for producing a first intermediate frequency in phase with said radar returns and another first intermediate frequency 90° out of phase with said radar returns; quadrature hybrid generator means, receiving a second local-oscillator signal from said modulator for providing a local oscillator output in phase and another 90° out of phase with said second local-oscillator signal; a pair of balanced mixers, one said balanced mixer receiving the in-phase frequencies from said single sideband generator means and said quadrature hybrid means, and the second said balanced mixer receiving the 90° phase-shifted frequencies from said single sideband generator means and said quadrature hybrid means, for generating one second intermediate frequency in-phase with and one second intermediate frequency phase shifted by 90° from said in-phase frequencies; a sum amplifier receiving outputs from each of said pair of balanced mixers, for generating the detected radar returns from one of said frequency channels; a difference amplifier receiving outputs from each of said pair of balanced mixers, for generating the detected radar returns from the second of said frequency channels.