SU964512A2

SU964512A2 - Method of measuring interface profile of two media

Info

Publication number: SU964512A2
Application number: SU802910002A
Authority: SU
Inventors: Владимир Владимирович Половинко; Александр Дмитриевич Плутенко; Дмитрий Алексеевич Романов; Олег Иванович Абрамов
Original assignee: Московский Институт Инженеров Геодезии,Аэрофотосъемки И Картографии; Дальневосточный политехнический институт им.В.В.Куйбышева
Priority date: 1980-04-15
Filing date: 1980-04-15
Publication date: 1982-10-07

Description

(54) СПОСОБ ИЗМЕРЕНИЯ ПРОФИЛЯ ГРАНИЦЫ РАЗДЕЛА ДВУХ СРЕД (54) METHOD OF MEASURING THE PROFILE OF THE BORDER OF THE SECTION OF TWO MEDIA

Изобретение относитс к технике съемки открытых водных пространств с воздуха.The invention relates to a technique of shooting open water spaces from the air.

По основному авт. св. № 800642 известен рпособ, основанный на использовании фазового светодальномера , в котором после излучени непрерывно промодулированного по амплитуде излучени ослабл ют при приеме мощность излучени по функцииAccording to the main author. St. No. 800642, a technique is known based on the use of a phase-spaced-distance meter, in which, after radiation, a continuously amplitude modulated radiation is attenuated when receiving, the radiation power according to function

f (Z) - K/( z),f (Z) - K / (z),

где К - масштабный коэффициент;where K is the scale factor;

п - показатель преломлени воды; рассто ние проходимое излучением в воз духе; Z - рассто ние, проходимое излучением ,в воде,n is the refractive index of water; distance traveled by radiation in the air; Z is the distance traveled by radiation in water

и измер ют разность фаз принимаемого и излучаемого потоков 1.and measuring the phase difference of the received and emitted streams 1.

Этот способ обладает помехозащищенностью при определении границы между толщей воды идиом водного бассейна , однако не-дает возможности построить профиль толщи воды, т. е. выделить границу воздуха и воды.This method has noise immunity in determining the boundary between the water column and the idioms of the water basin, but it does not allow to build a profile of the water column, i.e., to distinguish the boundary between air and water.

Цель изобретени - устранение от eчeннoгo ограничител , т. е. определение профил толщи воды при сохранении достаточной помехозащищенности и дальности действи , соизмеримых с импульсными способами лазерного зондировани .The purpose of the invention is the elimination of the artificial limiter, i.e. the determination of the water column profile while maintaining sufficient noise immunity and range, commensurate with pulsed laser sounding methods.

Поставленна -цель достигаетс тем, что световой поток излучают одновременно в видимом и инфракрасном диапазонах спектра и измер ют раз10 ность фаз прин того излучени в обоих диапазонах при сканировании излучени в направлении приема.The target is achieved by emitting luminous flux simultaneously in the visible and infrared spectral regions and measuring the phase difference of the received radiation in both bands when scanning the radiation in the receiving direction.

На фиг. 1 -представлена схема устройства , реализующего способ, на фиг. 2 - графики, -иллюстрирующие зависимость отношени сигнеш/шум от глубины водного бассейна при различных услови х приема излучени .FIG. 1 is a diagram of the device implementing the method; FIG. 2 are graphs illustrating the dependence of the signal / noise ratio on the depth of the water basin under various conditions of radiation reception.

Claims

With the help of a transmitting optoelectronic system 1 of a phase light-dimmer, the luminous flux containing the components of the visible and infrared ranges, both modulated in amplitude, is directed to the determined interface. To scan the radiation field in the direction of reception of the stream reflected from the air-water interface and the bottom, a rotating mirror is used.

2. Reception30 to the opto-electronic system 3 should contain a block of light filters (not shown) for the separation of both components of the received radiation, for which the phase difference could be measured. In accordance with the known method, the received power is described by the expression Flt) 4, yF (tt), (1 o and maximum relative signal / noise ratio j-ect 2 1 e e similarity coefficients; H, l radiation propagation time,; F ( t) output power; c is the speed of light propagation in water; is the attenuation index for water. Curve A characterizes the dependence of the normalized signal-to-noise ratio (see Fig. 2); curve B - on signal change / noise when the reflection is regenerated not on the whole traces, and from individual elementary areas during scanning. In this case, this ratio is described by the expression I 1/2 () l - the characteristic size of the thickness of the elementary portion of the water in the receiving direction, limited by the intersection of the radiation and reception fields. Radiation in the infrared range, for which воз significantly increases, is perceived almost only reflected at the air-to-water interface. In the visible range, as in the known method, radiation can be received after reflection at the bottom. Thus, by the difference in the results of the studies in both ranges, it is possible to determine the position of the air-water boundary along the profile of interest and the change in the water column along the same profile. This increases the efficiency of using phase light range finders to study the bottom and surface profiles of water basins, not only for open seas and oceans, but also for irrigation facilities. When measuring the thickness of the water cover of rice checks in the range of 5 to 20 cm, the measurement error does not exceed 1 cm. Invention The method for measuring the interface profile of two media according to the author. St. 800642, which means that, in order to determine the profile of the water column while maintaining sufficient noise immunity and range, the luminous flux emits simultaneously in the visible and infrared spectral regions and measures the phase difference of the received radiation in both bands during scanning radiation in the direction of reception. Sources of information taken into account in the examination 1. USSR author's certificate on application 2734171 / 18-10, cl. G 01 C 13/00, 1979.