RU2069867C1 - Method of adjustment of radar stations - Google Patents

Abstract

FIELD: automated radar systems for observation of air space. SUBSTANCE: coordinates of reflecting object are measured and systematic errors of adjustment are determined; auxiliary radar station is mounted at distance equal to at least half radius of its action from radar station being adjusted; coordinates of air object are measured by means of both radar stations; discrepancy Δx, Δy between results obtained by means of both stations is determined and azimuth correction for radar station being adjusted is determined by means of definite formulae. EFFECT: enhanced accuracy. 1 dwg

Description

 The invention relates to the field of radar and can be used in automated radar systems for airspace control and air traffic control. Known methods for adjusting radars are based on the use of reflective or radiating objects, the position of which (coordinates) is precisely determined.

 Known methods for adjusting radar stations on local objects, the position of which is determined by optical or geodetic means. However, this requires the presence of separately standing reflecting objects on the ground or specially installed reflectors or emitters on the towers, which is expensive. Known methods of adjusting the radar for radio emission of the Sun or other celestial bodies require considerable time for its implementation and certain weather conditions. The closest in combination of features is the radar alignment method, in which aerial objects with accurately measured coordinates are used. The disadvantage of this method is the need for accurate measuring tools that do not have alignment errors.

 The essence of the invention lies in the fact that during the adjustment process, discrepancies Δx, Δy are determined between the rectangular coordinates of airborne objects, measured by two radars, spaced on the ground at a distance of not less than half the radius of the radar. Further, the obtained discrepancy values are used to determine, using special formulas, alignment errors (corrections) in the azimuth of the measured radar. When adjusting a specific radar, the second radar is auxiliary. It may have an azimuth adjustment error.

The schematic drawing shows the location of the aligned and auxiliary radar and an air object, the information from which is used for alignment. Adjustable radar 1 and auxiliary radar 2 determine the coordinates of the air object 3. Due to alignment errors, the measured coordinates of the air object will differ from its true coordinates, so that the coordinates of object 3 according to radar 1 (x ₁ , y ₁ ) corresponds to point 6, and according to Radar2 (auxiliary) (x ₂ , y ₂ ) point 8. The mutual distance of points 6 and 8 is characterized by differences of coordinates Δx, Δy. These discrepancies are unambiguously associated with misalignment errors in azimuth.

и для вспомогательной РЛС согласно формуле

Выражения (1), (2) предусматривают случай, когда ошибки юстировки по дальности и ошибки в координатах дислокации обеих РЛС отсутствуют.The proposed method for adjusting radar stations consists in placing an auxiliary radar at a distance of not less than half the radius of action of the adjusted radar, measuring the coordinates of any airborne object located in the range of these radars with both radars, and determining the differences between the rectangular coordinates of the airborne object according to the data of the adjusted and auxiliary Radar (Δx, Δy) and determine the magnitude of the correction in azimuth for the adjusted radar according to the formula

and for auxiliary radar according to the formula

Expressions (1), (2) provide for the case when there are no alignment errors in range and errors in the coordinates of the dislocation of both radars.

The rectangular coordinates of VO are related to the coordinates measured by the radar, the known relations X = Dcosβ, Y = Dsinβ,
where D is the range VO relative to the radar,
β azimuth BO relative to the radar.

После приведения координат к единой системе отсчета Х^o, Y^o координаты ВО по данным двух РЛС получают значения

где

координаты дислокаций РЛС, индекс "1" относится к юстируемой РЛС, индекс "2" к вспомогательной РЛС. Расхождения координат, приведенных к единой системе отсчета, равны

При наличии ошибок юстировки координаты ВО отличаются от истинных координат, так что

где X $\genfrac{}{}{0ex}{}{\text{o}}{\text{п}}$ , Y $\genfrac{}{}{0ex}{}{\text{o}}{\text{п}}$ истинные координаты ВО, a ΔX₁, ΔY₁, ΔX₂, ΔY₂ их отклонения, обусловленные ошибками юстировки РЛС. Следовательно, расхождения координат равны разности их отклонений:

C учетом соотношений (3) справедлива система уравнений

решением которой являются выражения (1) и (2).Accordingly, the deviations of the rectangular coordinates in the absence of range errors are equal

After bringing the coordinates to a single frame of reference X ^o , Y ^{o the} coordinates of VO according to the two radars get the values

Where

coordinates of radar dislocations, index "1" refers to the adjusted radar, index "2" refers to the auxiliary radar. The discrepancies of the coordinates reduced to a single reference frame are equal

If there are alignment errors, the BO coordinates are different from the true coordinates, so

where is x $\genfrac{}{}{0ex}{}{\text{o}}{\text{P}}$ , Y $\genfrac{}{}{0ex}{}{\text{o}}{\text{P}}$ true coordinates of VO, a ΔX ₁ , ΔY ₁ , ΔX ₂ , ΔY ₂ their deviations due to radar alignment errors. Therefore, the differences of coordinates are equal to the difference of their deviations:

Given relations (3), the system of equations

the solution of which are expressions (1) and (2).

 The main advantages of the proposed alignment method compared to the existing ones are the simplification of the alignment process, especially in territorial radar systems, the determination of corrections without removing the radar from normal operation, the use of random air objects flying in the coverage area of two radars during their operation in automated system. Analytical calculations and statistical modeling show that sufficient accuracy for determining corrections for survey radars can be obtained in 3-5 minutes with a survey period of 10 s.

Claims (1)

A method of adjusting radar stations (radar), which consists in measuring the coordinates of a reflecting object with subsequent determination of systematic errors in alignment, characterized in that the auxiliary radar is installed at a distance of at least half the radius of action of the adjusted radar, and both radars are measuring the coordinates of an air object (AT) located in the range of both radars, determine the discrepancies ΔX, ΔY between the coordinates of VO according to measurements of the adjusted and auxiliary radar and determine the correction value in azimuth d I, adjustable according to the formula radar

and corrections for auxiliary radar according to the formula

where X ₁ , Y ₁ and X ₂ , Y _{2 are the} rectangular coordinates of VO in the coordinate systems of the adjusted and auxiliary radars, respectively.