DE2328720A1 - PEILER - Google Patents

Description

LICENTIA

Patent administration GmbH

6000 Frankfurt (Main) 70, Theodor-Stern-Kai 1

Ulm (Danube), 5. June 1973 PT-UL / S chz / d eu UL 73/71

"Direction finder"

The invention relates to an arrangement for the automatic bearing of N waves present in a frequency casial.

To find N waves, it is known to set up "2 N antennas, and either in eiaer aaalogoia, Reehexunaschisi® die

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To process DF antenna voltage (DT-PS 1 l42 920) or digitize the direction finding information and subject it to suitable algorithms in a digital computer (DT-PS 1 248 754).

It is still known in direction finding technology that antenna steel because redundant information allows statistical influences to be reduced (DT-OS 2 150 434).

This can result in a very considerable number of antennas, who have an equal number of recipients and other input

r directions (DT-OS 2 007 049).

The effort can therefore be very considerable. A well-known way to reduce this effort is to introduce Switching means which, as required, select the antennas that are most favorable for the solution of the task (DT-OS 1 516 876).

The invention is based on the object according to the prior technology to further reduce the effort required.

The invention takes advantage of the fact that interference fields do not are stationary, so that snapshots that took place in the changes

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of the fields successively adapted time intervals, new Provide information. According to the invention is therefore of the for the resolution of N pelts, the number of antennas normally to be provided and thus also all other direction finding devices a part saved and the information lost in this way replaced by scanning the antenna information, the time intervals adapted to the changes in the fields follow one another.

The entire amount of information can then be used to solve the DF task algorithms similar to those already known for normal multi-wave direction finding.

In the case of the invention, it is often technological and computational advantageous if between the antenna system and the digital Preparation of the information an analog preprocessing, which acts as an information transformer or information filter, is switched.

The invention also allows multi-wave direction finding systems designed for N waves easily expand to a larger number of waves.

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For this purpose only the device according to the invention be provided, which allows to be adjusted by scanning the antenna information in the changes of the fields To increase the amount of information about the interference at intervals.

In the two-wave case, what is used as an exemplary embodiment there is an imaging system for a wave.

As is well known, the following applies to a two-wave incidence:

Voltage in the round duct ζ = A ^ ¹ * ^W l ^{t + Cp} l ^ + A ^ ¹ * ^W

Voltage in the bearing channel y = A.sina.e ¹ ^ i ^{+ <ί>} 1 + A "sina _o e ¹¹ 2 ^{+ Ci>} 2

Voltage in the bearing channel x. = A cosa.e ¹ ^ l ^{t + (p} i ^ + AgCos ^ e ¹ ^ 2 ^{+ (f>} 2 'A, A _p are the amplitudes of the 2 waves, CC ₁ , 0C _?, The amplitude

Lj _Λ ι Cj ο ^^ ^e circular frequencies and φ φ _ο the phases.

X ^ 1, &

At time t = 0, the first query is made.
The second time t = t is queried.

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The query is z. B. controlled in a form as in shown in the figure.

With the abductions /. ο will

Λ * 1 ₅ Z ₂ = e ^{i (} i>2; \ =

at time t »Ό / * z = A ₁ Z ₁ + ^A /

₊ A ₂ sin a _2/2

and at time t β t

Y ₂

x ₂ =

^A 2 ^sina i / 1 ^ I ^{+ A} 2 ^{sin (X} 2 S2

A ₂ cosa _2/2

Here, z 1, z_, y _1t y _o , X, x _{o are} measured voltage quantities. 14 14 14 _c

If the existing equations are solved in the computer /, the result for the still unknown quantities is:

1

^A i ^siaa i ^/ i

1 '2

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A ₂ sina ₂

1 X ₁ ⁷ I ^X 2 1 1

(3)

(5) (6)

In an intermediate process, the Tl ₁ ^ l must first be determined, if one sets B = A cosa. <f _Λ and B ₀ = A sino. ^ ₁ and represents

Bi

then B = ■ a tana., i.e. a real number, so it is known for this ( # means conjugate complex)

or

B = B B _n I

This gives the relationship in detail

^B IV - ^B 2 ^B :

0.

The expressions (1) and (2) are inserted into this equation,

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Ee is obtained for a quadratic equation a ₂ T ² + ib r ₂ - a * = O

mxt the two solutions

and a = y

ι, ώ 2 ^a

Expressions (1) to (6) are then entered with / 1 and 2 ^ 1.

The bearing values CL, a "can now easily be calculated from them. This solves the DF task for the two-wave case.

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Claims (1)

- 8 - UL 73/71 Patent claims 1.) Arrangement for the automatic direction finding of N waves present in a frequency channel, characterized in that a bearing system designed for M <N waves is specified and that a device is provided which scans the bearing information in the changes in the fields and which are adapted to successive time intervals Computer supplies, which executes the interference field resolution according to suitable, predetermined programs. 2. Arrangement according to claim 1, characterized in that there is between the antenna system and the device for scanning a device for analog preprocessing is located. 3. Arrangement according to claim 2, characterized in that the The antenna system of the DF system and the device for analog preprocessing are designed as a conventional DF system, k. Arrangement according to claim 2 or 3 »characterized in that the antenna system of the direction finding system and the device for analog preprocessing are designed as Adcock with a Watson-Watt direction finding device. 409851/0592 - 9 - - 9 - UL 73/71 5. Arrangement according to one of claims 1 to 4, characterized characterized in that the conventional direction finding system is fully developed and in parallel for both the original Bearing function as well as for multi-wave bearing can be used « 6. Arrangement according to claim 4 or 5 »characterized in that that the Watson-Watt direction finder with a standard viewing device is complete and the Adcock and the multi-shaft direction finder can be operated in parallel. 409851/0592 Blank page