SU1493962A1 - Switched radiometer - Google Patents

Abstract

This invention relates to a microwave measurement technique. The purpose of the invention is to increase the fluctuation sensitivity of a modulation radiometer while simultaneously measuring signals from N radiation sources for N≥2. The radiometer contains an indicator unit 1, a source 2 of a reference signal, a modulator - switch 3, M receiving channels 4, each consisting of a microwave amplifier 5, a quadratic detector 6 and a low frequency amplifier 7, M switches 8, N + 1 integrators 9, N - phase rc 10 modulation frequency, N operational amplifiers 11. The measured signals and the signal from source 2 are modulated by a multichannel modulator - switch 3 and alternately enter channels 4. Here the signals are amplified, detected, again amplified and through switches 8 come on int integrators 9. The average voltages obtained on them are fed to operational amplifiers 11, which produce differential voltages supplied to the indicator unit 1. 2 Il.

Description

(21) 4280874 / 24-09

(22) 07/09/87

(46) 07.15.89. Bkgp K 26

(71) Special Design Bureau of the Institute of Radio Engineering and Electronic Electronics, USSR Academy of Sciences

(72) B.C. Abl eov

(53) 621 .317.328 (088.8) (56) Nikolaev AG and Pertsov S.B. Radioteplolokatsi .-- M .: Soviet Radio, 1974, p.118.

USSR author's certificate K 761946, cl. G 01 R 29/26, 1978.

(54) MODULATING RADIOMETER (57) The invention relates to microwave measurement techniques. The purpose of the invention is to increase the fluctuation sensitivity of a modulation radiometer while simultaneously measuring signals from n sources of radiation for P & 2. The radiometer contains an indicator unit I, a source 2 of the reference signal, a modulator-switch 3, m of receiving channels 4, each consisting of a microwave amplifier 5, a quadratic detector 6, and an effort

(L

tel 1 HH3Koii frequencies, m switches 8, (n + lj integrators 9, n-phase rr iO modulation frequencies, n operational amplifiers 11. The measured signals and the signal from source 2 are modulated by a multichannel switch modulator 3 and alternately arrive into channels 4. Here

This invention relates to a technique for measuring on microwave and can be used in radiolocation.

The purpose of the invention is to increase the fluctuation sensitivity of a modulation radiometer while simultaneously measuring signals from n radiation sources for.

FIG. Figure 1 shows the electrical block diagram of the modulation radiometer; in fig. 2 shows timing diagrams of noise signals at the inputs of microwave amplifiers for n A and m 3 (diagrams a, b, and c) and at the inputs of five (n + 1) integrators (diagrams d, e, f, g, and sj.

The radiometer contains an indicator unit 1, the source 2 of the reference signal, the modulator-switch 3, (n + 1) whose inputs are respectively connected to the n inputs of the radiometer and the output of the source 2 of the reference signal, m receiving channels 4, whose inputs are respectively connected to the module outputs switch torus 3, microwave amplifiers 5, quadratic detectors 6 and low frequency amplifiers 7 connected in series in each of the receiving channels .4, m switches 8, whose inputs are respectively connected to the outputs m of channels 4, and the number of outputs each (n + 1), (n + 1) integrators 9, the input of the first of which is connected to all the first outputs m of switches 8, the input of the second connected to BCQ and the second outputs of these switches, etc., p-4) generator 10 modulation frequencies, the outputs of which are respectively connected to the control inputs of the modulator switch 3 and m switches 8, n operational amplifiers 1, the non-inverting inputs of which are respectively connected to the outputs of the first

14939624

the signals are amplified, detected, re-amplified, and through switches 8 arrive at the integrators 9. The average voltages obtained for them are fed to the operational amplifiers 1I, which produce differential voltages, delivered to the indicator unit 1. 2 Il.

n integrators 9, and inverter inputs - with the output of (n-bl) -ro integrator 9.

The radiometer works as follows.

The measured signals with noise temperatures T ,, T, ..., T and the signal from the source 2 T are modulated by a multichannel switch-modulator 3 so that each signal

alternately pulses of duration

 to

(where tn is the period of frequency mop + 1 o

The pulses) are fed to the input of each of the m receiving channels 4 (diagrams a, b and c in Fig. 2 for p 4)) B receiving channels 4 signals are amplified by microwave amplifier 5, detected by quadratic detectors 6, amplified by low frequency amplifiers 7 and arrive at the inputs of the switches 8,

I Operation of all m switches 8

synchronized so that on the first outputs of the i-switch there are impulses with an amplitude proportional to T, + T, and on the second outputs T + + TLJ; etc., and on (n + 1) -th outputs Te +. The pulses in each group in the adjacent channels in time will be

shifted to

P & I

. Impulses from each

The j-ro output goes to the input of the j-ro integrator 9 (diagrams g, d, e, g, and 3 in Fig. 2 for n 4 and m 3),

The synchronous operation of the modulator switch 3 and ha of the switches 8 is provided by a n-phase generator 10 of the modulation frequency F l / t, the outputs of the phase voltages of which are respectively connected to the control inputs of the switch modulator 3 and m switches 8, and

long I and single pulses

1 „equal or multiples of -4P,

The middle and (yarns from the output of the integrated output integral:) Ron 9 are fed to non-interruptible ones (input of the first, operational amplifiers II, all inverting rotors of which are connected to the output of the () th integrator 9. The resulting difference t, proportional, -T ,, ..., ,, and taken from the outputs of the operational amplifiers I, are fed to the n input of the indicator unit 1.

v

The fluctuation-sensitive modulation radiometer when a signal is generated from n sources S T l .p + 1 2,.,

 dip (-2), where Td is the fluctuation sensitivity of the modulation (- the first radiometer with n 4 and m 1.

Claims (1)

Invention Formula A modulation radiometer containing a series-connected source of a reference signal and a modulator-switch, the second input of which serves to connect the source under study to the m receiving channels, each of which contains a series-connected microwave amplifier whose input is the input of the receiving channel O2 g 4. iibr.i, detectg-; ; ;: v ;. and , -,, -, ,, laCTO -,; .vXn.n KOI I ;-) :, G, eggch ИИХС1Д.Г-; ; R echno n Kjl ,, .., T- b, r; b | nd feHe. dTo ;: h tt- -. ..} /.ch; i.,; j, 1tnd .--, - .. atop; :) o.pok, l and h; : v. -:; p .1, that, with DS. P-p; Hbji; C} i c1) luktuapioinoy hvstvitel {) g-rear and oaio oPeMeiiHoru omepS10 PIR signals from IG T (OHS:, OV IZZLZ cheni;,) t p $. 2, modulator-switch supplying copolymers of the gel; and p-1 rholami for iodkkpgenii source sources and ir outputs, entered w It) of switches, phs. / Dy kots.rk are mute with outputs of seotv - / storing receivers KiHa.ioiJ, and klch i-gy 1 - m output from n + 1 outputs KOTof: j is connected by input f i-rn from n + 1 centuries of integrated integers - O Topf-iH, n operating systems -), i e- and 1 n: which inputs are connected to the outputs and integrators corresponding to 1; r i -rB: Hiio, and the next input is connected to v. sdsdom (r.) go and s-grat., and ihod- with and entrances the indicator block, and the p. of outputs of the p-phase gengra of the modulation frequency coefficients coe uJHeHbi-g.rlil kitstgmi vohoamt respectively - with p1. Shil 1ir klk1klt9 -. its, () - H aykhod ss sawed with i, i- ravl uadam lekhodom ms DU IYATooch -iK ie-- the key, R. every ig la output; .ov- mod 7ytor-h ts-: Кпюч..г; : t connect ;; g; НХ.1ДОМ соо i eTCTi; iyv hior (3; relative ka-. ... on ..; a.