JPS63275207A - Antenna apparatus - Google Patents

Abstract

PURPOSE:To correct the error of a composite electric field by providing a beam direction error correction processor, which changes the setting of some elements among divided antenna groups so as to minimize the error electric field of the whole divided antenna. CONSTITUTION:The beam direction error correction processor 7, which adjusts the set phase of phase shifters Ph1, Ph2,..., PhN so that the output signal phases of a first composer 1 coincide with each other, is provided between a beam control processor 5 and a phase shifter drive circuit 6. Then, the beam direction error correction processor 7 changes the setting of some elements among the divided antenna groups Ea1, Ea2,...EaN so as to correct the error electric field of the whole divided antenna. Accordingly, a deep zero point is formed in the desired direction of a monopulse difference pattern as the output of a 180 deg. hybrid. Thus, the direction error of the monopulse difference pattern due to a quantized phase error can be decreased.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an antenna device that performs combined beam scanning of the entire antenna by changing the phase of radio waves incident or radiated from a plurality of element antennas. be.

[Conventional technology]

Figure 4 shows, for example, Nikkei Electronics 1972.7゜1
FIG. 7 is a diagram showing the configuration of a conventional antenna device, which was written with reference to the one shown in No. 7 pp. 84 to 101.

In the figure * Ea' t F! a2r, ”'e B
11N is an element antenna.

Pfil, pH2, . . . , PlIN is a digital phase shifter, (11, +21 is a first synthesizer that synthesizes η elements, respectively.

(3) is a phase signal output terminal of 1800-1 hybrid as the second combiner, PS is a phase signal output terminal of 18G'/- hybrid (3), Pd is a difference signal output terminal of 180''/S hybrid (3), and (4) ) is a receiving ffl, (51 is a beam control processor, and (6) is a phase shifter drive circuit.

Next, the operation will be explained.

Element antenna Ba1, Ba2,..., BaN
The radio wave signals received are passed through phase shifters Ph1 and Pfi2.
,..., the phase can be changed by PhN. After that, the above radio wave signals are combined by 1 combiner (1+, (21) by η pieces. The combined signals are 81 and 8
Set it to 2. A signal i91+82 is output from the chaotic signal output terminal P8 of the next-stage 180° hybrid (3), and a signal 81-82 is output from the difference signal output terminal Pd. The signal output from the hybrid is transmitted to a receiver (4). When detecting the direction of arrival of a radio wave, detection is normally performed based on information on the amplitude and 9 phases of the ratio (S1+82)/(81-82) of these two signals. At this time, the beam control processor (5).

Depending on the beam scanning direction, phase shifters Ph1, Ph2,
..., calculates the setting amount of PhN, and according to the result, the phase shifter drive circuit (4) operates the phase shifters Ph1, Ph2,
..., Set PhN. For example, when maximizing the gain in an arbitrary direction θS, the element antenna Ba1 in the above direction
．． Ea2y..., the phase of the received electric field of BaN is Pl
, P2 , ..., PN, the phase Q in phase with this is
l, Q2. ..., a phase change amount of QN (Q1=-Pl) is given to each digital phase shifter. When the number of bits of the digital phase shifter is M, the minimum phase change amount θB is given by the formula il1.

θB = 56072”il
+When this digital phase shifter is used, the actually set phase q1 is given by equation (2).

qi=(Qi/θB)xθB(2) ([ ] represents the nearest integer) [Problem to be solved by the invention] Since the conventional antenna device is configured as described above, one phase setting and the next An error e1 is caused by the equation (3).

a1=qi −Qi (3)
The above e1 is called a quantization phase error. This quantization phase error e1 causes a direction error in the turn due to the mono-curse difference, and a rise in the side rope.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to obtain an antenna device that reduces the direction error of a monopulse difference pattern caused by the above-mentioned quantization phase error.

[Means for solving problems]

The antenna device according to the present invention is provided with a beam direction error correction processor that changes the settings of some elements in the two-divided antenna group so as to minimize the error electric field of the entire two-divided antenna. be.

[Effect]

The antenna device according to the present invention uses a beam direction error correction processor to change the settings of some elements in a multi-divided antenna group so as to correct the error electric field of the entire one-divided antenna, A deep zero is formed in the desired direction of the monopulse difference pattern as the output of .

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In Figure 1, (7) is the beam control processor (5)
The beam direction error correction processor is provided between the phase shifter drive circuit (6) and the phase shifter drive circuit (6), and the rest is the same as the conventional device shown in FIG.

Next, the operation of the beam direction error correction processor (7) will be explained.

FIG. 2 is a diagram showing received electric field vectors in the θS direction of 1 to η elements of the array antenna shown in FIG. 4. In the figure, the solid line is an electric field vector when a quantization phase is given, and the broken line is an electric field vector when an analog phase is given.

Due to the quantization phase error, an error electric field vector Br arises. In order to correct this Er, it is sufficient to delay the setting of n elements expressed by the 9th order equation by θB when the amount indicated by φ in FIG. 1 is positive, and advance it when φ is negative.

With this, F! The error with the composite electric field when a shear analog phase of r #O is given is corrected. Therefore, when the beam is scanned in the 08 direction, the output from the 180° hybrid output terminal Pd in the θS direction becomes significantly smaller than before correction. That is, the signal ratio (81+82)/(81
+82) increases the detection ability as the Inukikuna Gai radar system.

The above procedure is shown in chart 70 of FIG.

〔Effect of the invention〕

As described above, according to the present invention, the beam direction error correction processor corrects the error in the two combined electric fields by changing the first phase setting, so the device can be made inexpensive, and
This has the effect of obtaining a product with a high degree of a.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of an antenna device according to an embodiment of the present invention, FIG. FIG. 3 is a flowchart showing an embodiment of the present invention, and FIG. 4 is a diagram showing the configuration of an antenna device according to the conventional invention. Symbols in the figure, EaL"a2+..., BaN are element antennas. pH1, Ph2,..., PhN are phase shifters, 11
1, +21 is a combiner, (3) is a 180° hybrid, (4) is a receiver, (5) is a beam control processor,
(6) is a phase shifter driving circuit, and (7) is a beam direction error correction processor. Note that the same reference numerals in Figure 9 indicate the same or corresponding parts.

Claims (1)

[Claims] a plurality of element antennas, a plurality of phase shifters respectively connected to the element antennas, and a plurality of first combiners that combine the outputs of the element antennas after passing through the phase shifters;
a second combiner that further combines the outputs of the first combiner; a receiver connected to the second combiner; a phase shifter drive circuit that drives the phase shifter; In the antenna device, the beam direction error correction processor adjusts the phase setting of the phase shifter so that the output signal phase of the first synthesizer matches the beam control processor. An antenna device provided between a processor and the phase shifter drive circuit.