DE2014676C3 - Two-channel direction finder - Google Patents

Description

β =

It should be:

¹ BQ

= 0.

The invention relates to a two-channel direction finder for bearing electromagnetic waves, with two Antenna voltages are used which are perpendicular to each other in their azimuthal characteristics.

In the case of a linear two-channel distributor, the two channels noise independently of one another and with the same amount of noise. If a wave with the amplitude A is incident at the angle α, a stretched light spot is displayed on the screen, with the wave and the noise being superimposed linearly.

The display a fine structure is seen, which consists of the written by the electron beam during the observation time lines exactly, this applies to a b ^r, photograph with the exposure time T ₁ when the persistence of the screen is short against this is the case of direct observation of the viewing screen

First, Q is calculated:

Q = f (X ₁ sin λ - y, cos afdt ο

= B sin ² λ - C sin 2 <x + D cos ² λ , where

ß = / * fdi; ο

C = Jx _{1 Λ} dt ο

and

is.

D = fy \ dt
ο

The DilTerential Quotient of Q is

= (ß - D) sin 2λ - 2 C cos 2.x

and the hint)

So is

tan 2 * =

2C B-D '

Ix

tan 2λ =

2 JV ₁ ^ ₁ German
ο

T T

Jx? dt - / y \ dt

O 0

The design of the two-channel direction finder according to the invention results from this knowledge.

In the following, embodiments are given for a two-channel viewing memory in which the control the sight tube takes place in the manner indicated by the invention

Such a circuit arrangement is characterized according to a development of the invention, that a multiplier is provided, at whose inputs the antenna voltages are applied and the output of which is connected via a low-pass filter to the one deflection unit of the sight tube and that two squaring members are provided, one with its input with one antenna voltage and the other with its input with the other Antenna voltage are connected and their outputs are connected to a differential element, its output via an integrator with the others Deflection unit is connected to the sight tube

Another circuit arrangement for realizing the conditions for a two-channel divider according to the The invention is characterized in that the antenna voltages each form a sum and a difference Element are fed and that their outputs on the one hand via a multiplier and a low-pass filter with one deflection unit of the sight tube and, on the other hand, each with a squaring element are fed to a difference-forming member, the entrance of which via a low-pass with the other Deflection unit is connected to the sight tube

Instead of the antenna voltages, the circuit arrangements described can also be used by the Antenna voltages derived voltages are supplied, the z. B. from the intermediate frequency part known two-channel receiver can be obtained.

ίο In the fig. 1 shows the block diagram for the first of the circuit arrangements described. In it, y and χ are the antenna voltages or voltages derived from them that z. B. are entered together into a product-forming member II and rest on a pair of plates of the sight tube via a low pass. On the other hand, the voltages χ and y are each given via a squaring element Q and the squares x ² and y ^{2 are} fed to a difference-forming Gfied ± X.The difference (x ² - y ² ) reaches the other pair of deflector plates of the viewing tube via a low-pass filter.

The block diagram of the circuit arrangement described as the second is reproduced in FIG. The voltages χ and y are each fed to a sum and a difference element (± Σ, Σ). The sums or differences are squared in the terms Q and subtracted ± Σ from one another in a further term which forms the difference, so that the product Axy remains, which is fed to the one pair of deflection plates of the sight tube via a low pass. The sum or difference voltage {xfy) and (x-y) are also fed to a multiplier II. The output of this element is the difference {x ⁷ -y ² ) , which is fed to the other pair of deflection plates of the sight tube via another low-pass filter.

With a direction finder according to the invention, you get an ambiguous image on the sight tube must still be made clear by suitable means, but these are the advantages that one can obtain through the use the invention receives, compared to this disadvantage, which, as said, can also be eliminated, considerable.

1 sheet of drawings

Claims (4)

Patent claims: 1. Two-channel direction finder for direction finding of electromagnetic waves, with two antenna voltages are used, which are perpendicular to each other in their azimuthal characteristics, thereby characterized in that the one deflection unit of the sight tube of the two-channel direction finder is the product of the antenna voltages or of these derived voltages via a low-pass filter and the other deflection unit of the sight tube Difference from the squared antenna voltages or voltages derived from these are supplied via a low-pass filter. 2. A circuit arrangement for realizing the conditions for a two-channel direction finder according to claim 1, characterized in that a multiplier is provided, at whose inputs the antenna voltages are applied and whose output ij6er a low-pass filter is connected to the one deflection unit of the viewing tube and that two squaring elements are provided having one an antenna voltage and _t the other are connected to its input to the other antenna voltage at its input to the and whose outputs are connected to a diffcrenzbildendes member whose output is connected via an integrator to the other deflection unit of the sight tube 3. Circuit arrangement for realizing the conditions for a two-channel divider according to claim 1, characterized in that the antenna voltages are summed up by one and one difference-forming element are supplied and that the outputs thereof on the one hand via a multiplier and a low-pass filter with the one deflection unit the sight tube and, on the other hand, are fed via a squaring element each to a difference-forming element, the output of which is via a low-pass filter is connected to the other deflection unit of the sight tube 4. Circuit arrangement according to one of claims 2 and 3, characterized in that it is instead the antenna voltages are supplied from these derived voltages. ! To equate Tetwa with NachJ Leuchtdeuer. It is difficult for the human observer to determine the bearing direction from this with such great accuracy to determine how this is possible using today's electronic means It is the task of the Invention of specifying a direction finder, which 'from the noisy bearing information an angle of incidence which comes closest to the right one This object is achieved according to the invention in that the one deflection unit of the sight tube Two-channel viewing direction finder the product of the antenna voltages or voltages derived from these a low-pass filter and the other deflection unit of the sight tube the difference between the squared antenna voltages or voltages derived from these be fed via a low-pass filter. This result is reached on the basis of the following considerations: The noise in the channels χ and y is given njtjvmdnjt). Furthermore, the signal wave is given by Sx (t) = A cos «o cos ω t Sy (t) = A sin« o cos tat The total stresses x \ (t) = S _x + n _x y _x (t) = Sy + ny are then applied to the channels. Imagine a straight line at the angle α through the coordinate intersection. It is then known that the distance Δ between a point and this straight line is Δ = χι sin «- y \ cos«. This as yet unknown straight line with the angle must now be determined in such a way that the measuring points x \ and y \ are optimally used. Since this straight line at the angle "should correspond as closely as possible to the sign?" Straight line at the angle "o, the sum of the squares is formed from the distances Δ (ί) and the angle" is determined from its minimum 10 15th 20th 25th 30th 35