SU1631485A1 - Apparatus for measuring height of the lower boundary of clouds - Google Patents

Abstract

The invention relates to meteorology and permits an increase in the accuracy, reliability and reliability of a device for measuring the height of clouds. The emitter 1 short light pulses sends them vertically upwards. The echo signals reflected from the cloudy layer arrive at the photodetector 2. The threshold device 3 ensures the selection of the signal corresponding to the lower cloud boundary. The time interval between the sending and receiving of the pulse corresponding to the height of the clouds is formed in the time interval former 4 and digitized into the ADC 5. The resulting digital codes are processed and stored in the ordering device 6. Blocks 7-10 determine the average values of quantiles, determine the maximum distance between quantiles, and compare this distance with the threshold. According to the results of processing and comparison, the state of cloudiness, the number of cloud layers and the distance to the lower boundary are determined. 1 il. cl

Description

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The invention relates to meteorology, in particular to instruments for measuring the height of the cloud base.

The purpose of the invention is to improve the accuracy, reliability of determining the height of the lower boundary of clouds and reliability of the device.

The drawing shows a block diagram of the device.

The device contains a probe of light pulses, a photoreceiver of 2 reflected pulses, a threshold device 3 with an amplifier, a time meter 4, an analog-to-digital converter 5, an ordered sampling circuit 6 with a memory device, a counter 7 that defines quantile boundaries, circuit 8 determining the mean values of quantiles, scheme 9 of searching for the maximum distance between quantiles, comparison scheme 10, scheme 11 for determining the characteristics of the selected cloud base lowering codes, block 12 issue

The device works as follows.

Emitter 1 sends short light pulses. The echo signals, which are reflected from the cloud layer, depend on the optical density of the cloud, arrive at the photodetector 2. The electrical impulses from the output of the photoreceiver arrive at the threshold device 3, which ensures the separation and fixation of the signal received as reflected from the lower boundary of the cloud. Shaper 4 separates the time interval between the probe and reflected pulses. The analog-to-digital converter 5 for a single probe pulse converts the time interval to a digital code.

The measurement codes for a sliding or piecewise sliding time interval are processed by the device 6, which compares the codes in magnitude and writes them to the sequential addresses of the output memory in order of increasing or decreasing numerical values. The number of addresses of the output storage device is equal to the number of measurements in a sliding sample. The operation of circuit 6 is repeated when the next code or group of codes is received.

Schemes 7-10 carry out the allocation of codes related to the lower cloud limit. The most simple implementation of these schemes provides information in conditions of two-layer and broken clouds.

Block 8 determines the average height of the clouds for the upper and lower quantile and for the sample as a whole and passes it to block 9. The boundary of quantiles, i.e. the number of measurements is determined by the state of the control counter 7. In scheme 9, the distance between the upper and lower quantiles is found (in the simplest case, the difference between the average values of the two quantiles) and compared with the maximum difference obtained from the previous enumeration of values. If the new difference is larger, in block 9 its value is memorized, as well as the corresponding value of the number of measurements. Sequential search of these values is carried out by a pulse counter 7. At the end of the entire search cycle, circuit 10 compares the maximum value found during the search.

0 differences with a threshold value The result of the comparison from block 10 and the number of measurements corresponding to the maximum difference from block 9 are fed to circuit 11. The latter forms the output characteristics for the entire sample (for example, averages and extreme values) or for the selected lower layer codes . In the drawing, the solid lines show the links of the circuit 11 for the simplest case of outputting only the average value, namely the case when the search quantile averages are already stored in block 9. The link with block 6 for the general case is shown by a dotted line

5Main advantage of the invention.

lies in the ability to obtain reliable measurements in difficult conditions of broken and multi-layered clouds, as well as in reducing random

Claims (1)

0 errors, the exclusion of spurious signals and emissions. The device allows to ensure continuous operation of the device with a constant readiness of the output data, and due to the sliding processing of single soundings, increase the resource and, consequently, the reliability of the device. Formula of the Invention A device for measuring the height of the cloud bottom, containing successively connected receiving unit, threshold device , shaper of the time interval between probe and reflected light pulses, emitter, blocks are connected to the input of the latter 5 processing and issuing a signal, characterized in that, in order to improve the accuracy and reliability of the results and reliability of the device, the processing unit is designed as an analog-digital converter, a formation circuit ordered sampling of cloud heights, successively connected quantile averages, quantile maximum distance search schemes and comparison schemes with a threshold value, as well as a counter whose outputs are connected to the control inputs of these circuits, and characteristics determination schemes codes, while analog-to-digital conversion The teller is connected to the information input of the quantile mean value determination circuit through a circuit for generating an ordered sample of cloud height codes; the second output of the maximum distance quantile search circuit is connected to the information input of the code characteristic chart, the control input of which is connected to the comparison circuit output .