Variable resolution radar for tropospheric sounders

Claim 2

In measuring and displaying the altitude and details of strata of distinct refractive indices of the troposphere, the method comprising the steps of: generating continuous microwave energy; repetitively linearly modulating the frequency of the microwave energy; vertically radiating from a directional antenna a relatively narrow beam of said microwave energy; focusing and vertically fixedly directing directional receiving antenna means to substantially the same space illuminated by the radiated beam to receive any microwave energy reflected vertically downward from overhead atmospheric strata; combining outgoing and reflected energy in a low flicker noise mixer to generate beat frequencies which instantaneously are functions of the altitude of said reflecting strata; displaying said beat frequencies in terms of altitude; and varying the range of frequencies of said microwave energy for varying the resolution of the display.

Claim 3

In measuring and displaying the altitude and details of strata of distinct refractive indices of the troposphere, the method comprising the steps of: generating continuous microwave energy; repetitively linearly modulating the frequency of the microwave energy; vertically radiating from a directional antenna a relatively narrow beam of said microwave energy; focusing and vertically fixedly directing directional receiving antenna means to substantially the same space illuminated by the radiated beam to receive any microwave energy reflected vertically downward from overhead atmospheric strata; combining outgoing and reflected energy in a low flicker noise mixer to generate beat frequencies which instantaneously are functions of the altitude of said reflecting strata; displaying said beat frequencies in terms of altitude; and varying the range of frequencies of said microwave energy for varying the resolution of the display.

Claim 4

In measuring and displaying the altitude and details of strata of distinct refractive indices of the troposphere, the method comprising the steps of: generating continuous microwave energy; repetitively linearly modulating the frequency of the microwave energy; vertically radiating from a directional antenna a relatively narrow beam of said microwave energy; focusing and vertically fixedly directing directional receiving antenna means to substantially the same space illuminated by the radiated beam to receive any microwave energy reflected vertically downward from overhead atmospheric strata; combining outgoing and reflected energy in a low flicker noise mixer to generate beat frequencies which instantaneously are functions of the altitude of said reflecting strata; displaying said beat frequencies in terms of altitude; and varying the range of frequencies of said microwave energy for varying the resolution of the display.

Claim 5

In combination in a system for displaying a cross section of the refractive strata of the troposphere, said system comprising: a microwave generator with a frequency determining circuit; a frequency determining means having a resonant frequEncy which, over a predetermined range, is a linear function of a variable direct current; a sweep current supply for generating a succession of straight-line voltage ramps; means for applying said voltage ramps to said frequency determining means for linearly varying the microwave frequency of said generator; stationary antenna means for forming a relatively narrow beam, said antenna means being disposed to aim vertically said beam,; plural cascaded amplifier stages coupling the output of said generator to said antenna means; a low flicker noise mixer of microwave frequencies; plural cascaded stages coupling the receiver terminal of said antenna means to one input of said mixer, the other input of said mixer being coupled to the output of said generator for combining outgoing and incoming microwave energy for generating beat frequencies; and display means for showing said beat frequencies, said display showing said beat frequencies in terms of the vertical height of atmospheric strata from which said energy is reflected.

Claim 6

In combination in a system for displaying a cross section of the refractive strata of the troposphere, said system comprising: a microwave generator with a frequency determining circuit; a frequency determining means having a resonant frequEncy which, over a predetermined range, is a linear function of a variable direct current; a sweep current supply for generating a succession of straight-line voltage ramps; means for applying said voltage ramps to said frequency determining means for linearly varying the microwave frequency of said generator; stationary antenna means for forming a relatively narrow beam, said antenna means being disposed to aim vertically said beam,; plural cascaded amplifier stages coupling the output of said generator to said antenna means; a low flicker noise mixer of microwave frequencies; plural cascaded stages coupling the receiver terminal of said antenna means to one input of said mixer, the other input of said mixer being coupled to the output of said generator for combining outgoing and incoming microwave energy for generating beat frequencies; and display means for showing said beat frequencies, said display showing said beat frequencies in terms of the vertical height of atmospheric strata from which said energy is reflected.

Claim 7

The combination defined in claim 2 comprising further: a delay line coupled in the circuit between the output of said generator and said mixer, the amount of delay being adjusted to approximately equal the total delays of all amplifiers and signal circuitry between said generator, said antenna means and said mixer.

Claim 8

The combination defined in claim 2 further comprising: means for selectively varying the length of said ramps for varying at will the excursions of the frequency of said microwave generator to alter the resolution of said system.

Claim 9

The combination defined in claim 2 further comprising: an adjustable delay line coupled between the transmitter terminal and the receiver terminal of said antenna means, the amount of said delay being adjustable to amounts corresponding to predetermined altitude-ranges.