SU731409A1 - Optical device for sounding atmosphere - Google Patents

Description

The invention relates to hydrometeorological instrument making and is an optical device for sounding the atmosphere. The device can be used to measure the atmospheric attenuation coefficient along the sounding path and to measure the height of the cloud base.

Optical atmospheric sounding devices are known based on the location method for measuring and processing the backscatter signal.

The main disadvantage of devices measuring the profile of the attenuation coefficient distribution along the sounding path and the height of the lower boundary of the clouds is that they do not take into account the change in the scattering indicatrix when sounding a non-uniformly turbid atmosphere. This is an irivodnt to the effect of significant methodological errors in measuring the profile of the atmospheric attenuation coefficient and the height of the cloud base even with the introduction of approximate analytical dependences of the backscatter coefficient on the attenuation coefficient.

Closest to the invention is the height meter of the cloud base 2, which contains a control unit connected to the radiator and to the de 2

signal photon, a photodetector, input to the signal detector and an electronic counter connected to the threshold device, which in turn is connected to the output of the video signal amplifier. The video amplifier is connected to the output of the signal detector via its input. A square distance compensation device is installed in front of the photoreceiver. AT

10 of this instrument, the echo envelope with a sufficient degree of accuracy reflects the change in the backscatter coefficient along the sounding path within the optical range, where

15 single scatter approximation. However, for practical needs, including for measuring the height of the lower boundary of clouds, it is necessary to intend along the sounding path not the backscattering coefficient, but to restore the attenuation coefficient.

When the atmosphere is created by a short optical emulsion, the envelope of the echo signal P (Z) is not corrected by an equation that depends heavily on the attenuation coefficient, which does not allow it to be measured accurately enough.

The purpose of the invention is to increase the measurement accuracy of the attenuation coefficient profile 30 along the sounding path. The goal is achieved by the fact that the optical device for sounding the atmosphere, which contains an equating unit, a radiator, a photodetector, a computation device, a signal detector, an electronic counter, is equipped with an connected input to the equilibrium unit, and one of the outputs is connected to the detector input by a but-range view unit connected in series a gated amplifier whose inputs are associated with a photodetector and a range-of-view unit, a nicke detector, also connected to the unit with a range-of-sight blocking unit m and resolver to whose input the output nodklyuchen electronic counter. The drawing shows a block diagram of an optical atmospheric sensing device. The device contains a control unit 1, an emitter 2, a signal detector 3, an electronic counter 4, a range b survey block, a photodetector 6, a gated amplifier V, a peak detector 8, a block 9 of memory, a resolver 10 n device And compensation. The operation of the device is based on the fact that in real atmosphere one can distinguish finite intervals Zi, within which the linear relationship between (j and 0, i.e. within the limits of such PJZ,), .a (Z), - attenuation coefficient where a (Z) is the distance Z along the sounding path; P (Z) is the backscatter coefficient at the distance Z along the sounding path. In addition, the attenuation coefficient profile can be approximated by a linear-piecewise function and then on each approximation area chosen so that it simultaneously fulfills the r-iTii PxiTto.GGL TLi / DTLTTTi TTTLJCrn / rt coupling condition o we can assume that p (Z;): / C, a (Z,) Ki- (a, + b, Z), where Og and bj are the coefficients of a linear function approximating the a (Z) profile in a given area Zi. To determine the unknown coefficients i, bi, and Ki, on each interval Zj, several measurements must be taken to obtain a series of values of P (Zi) -2a; Z, .z2 i III, P, (Zi,) A-Ki (ai + biZi, } e -2a Z- and. Pg (Zi,) A-Ki {ai + biZi.,) e; (1) -2n, .Zi, b..ZP, (,) e (,) (ai +, e - -. All points Z, - - 2 / belong to the interval Zj. For the first interval. N, we have four equations and four unknowns (i; y (i; bi). Such a system of equations can be solved on an EBM using known methods (Newton's metod, iteration method). If the hardware parameter A remains constant in the sounding process and the last measurement point on the previous the measurement interval coincides with the first point of the subsequent interval Zi, then for all intervals c it is necessary to measure only two values of P (Zi) and then solve the system of all pz two The atmospheric sounding device works as follows: The control unit 1 starts the emitter 2, the signal detector 3 and the distance viewing unit 5. Simultaneously, the Range but-out review unit outputs a strobe signal corresponding to the first reference point on the strobed amplifier 7 and opens it. dispersed by the atmosphere, the passage through the recency device, it drops onto the photodetector 6, and then to the gated amplifier 7 and from it to the peak detector a. A constant voltage proportional to the magnitude of the reflected signal from one of the selected points of the interval Zi is memorized in the memory unit 9. At the same time, the electrical signal from the photon receiver 6 is fed to the detector signal 3 and then to the electronic counter 4, which measures the distance to the selected point on the probing path. Then, the measured distance from counter 4 and the signal from memory block 9 go to solving device 10, which solves equations like the system (1, numbers profile a (Z) along the sounding path. At the last moment of transition from one point measurement to another unit 5 of the range overview, resets the peak detector 8. Formula and 3 a bout e and II Optical device for sounding the atmosphere containing a control unit connected to the emitter and signal detector, to the input of which is connected to A receiver with an input compensation device, and an electronic counter to the output, characterized in that, in order to improve accuracy, it is equipped with a connected input to the control unit, and one of the outputs - to the detector input with a range viewing unit, connected in series by a gated amplifier, the inputs of which are connected to the photo print

and a range-of-view unit, a peak detector, also connected by an input to a no-dalcost unit, a storage unit with a matching device, to the input of which is under (the output of the electronic counter is switched off).

Sources of information taken into account in the examination

1.Patent of France No. 2208527, cl. G 01W 1/00, 1977.

2. Authors certificate of USSR L 563658, cl. G 01W 1/00, 1977 (prototype).

Claims (1)

Claim An optical atmosphere sensing device comprising a control unit connected to an emitter and a signal detector, to the input of which a photodetector with a compensation device at the input is connected, and to the output is an electronic counter, characterized in that, in order to improve accuracy, it is equipped with a connected input to the unit control, and one of the outputs - to the detector input by a range review unit, connected in series by a gated amplifier, the inputs of which are connected to a photodetector and a range view unit, peak detectors a torus, also connected by an input to a range-viewing unit, a storage unit, and a decider, to the input of which an electronic counter output is connected.