JPS6373704A - Antenna adjusting method - Google Patents

Abstract

PURPOSE:To obtain a desired antenna characteristic by comparing a reference distribution and a distribution projected from the total of amplitude of the modules at each row and column and rearranging the modules so as to minimize the difference. CONSTITUTION:When a Y1 column has a lower distribution than the reference distribution and a Y2 column has a higher distribution, an active module y1 having a small amplitude in the Y1 column and an active module y2 having a large amplitude in the Y2 column are selected out and they are replaced with each other to make the distribution close to the reference distribution. The procedure is repeated for each column and each row to bring the entire distribution closer to the reference distribution. Thus, the antenna characteristic is improved by the rearrangement even with a large dispersion in the modules, then the modules are manufactured easily and inexpensively.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an antenna adjustment method for determining the arrangement of modules of an electronic scanning antenna that electronically scans a beam.

[Conventional technology]

A conventional electronic scanning antenna will be explained.

Figure 4 shows a conventional electronic scanning antenna.

81 to an are element antennas, b1 to bn are active modules composed of a phase shifter, a high output amplifier, a low noise amplifier, a transmitting/receiving switch, etc., C is an lE power distribution and synthesis circuit, d is a duplexer, and e is a transmitter.

f is determined by the receiver, and g is determined by the control circuit. FIG. 5 shows the inside of active modules b1 to bn.

(1) is a transmit/receive switch, (2) is a high output amplifier, (3)
is a low noise amplifier, (4) is a phase shifter, (5i is a control signal line connected to MI control circuit g, and (5b) is a microwave transmission line. During transmission, this electronic scanning antenna is connected to the transmitter θ. The signal from is distributed by the power distribution/synthesis circuit C,
The phase shifters 14) and high-power amplifiers 12) in the active modules b1-b control and amplify the phase shift, and the element antennas a1-I! Supply In. During reception, the signals incident on the element antennas 81 to 8n are phase-shifted to the low noise amplifiers (3) in the active modules b1 to bn. 5
14), the signals are amplified and phase controlled, and the signals are combined by the power distribution/synthesizing circuit C and input to the receiver (5).

Further, in this antenna, the beam direction of the wrinkled antenna can be controlled by controlling the phase shifter (4) by the control circuit g.

However, in the antenna configured in this way, if the excitation amplitudes of the element antennas a1 to an are made equal amplitudes, the antenna at the low side lobe level cannot reach %['. Therefore, density distribution by thinning is often used in active phased array antennas as a method of creating amplitude distribution.

To explain the density distribution due to thinning at the time of transmission, by combining the signal fed from the power distribution/synthesizing circuit with elements that emit transmission power and elements that do not emit transmission power using uniform distribution, the amplitudes of each element are combined into the desired amplitude distribution. This is how it turned out. FIG. 6 shows an example of the arrangement of elements that transmit and receive and elements that do not transmit and receive. In the figure.

The ○ marks in (6) are elements that transmit and receive, and the x marks in (7) are elements that do not transmit and receive. FIG. 7 shows the synthesized amplitude distribution. As shown in Figure 7, the elements that emit transmit power and the elements that do not emit transmit power are arranged so that the synthesized amplitude distribution has a thicker amplitude in the center (smaller amplitude in the periphery). The explanation is as follows, but the same is true when receiving.The transmitter 9 that outputs the transmitting power is amplified by the low-noise amplifier (3) and is transmitted to the power distribution/synthesizing circuit C by combining the elements shown in Fig. 7. Achieve the amplitude distribution shown in .

[Problems to be Solved by the Invention] - The above active module does not actually have equal amplitude due to variations in the high output amplifier, low noise amplifier, etc.

Therefore, even if the active modules are arranged in the above arrangement, the desired amplitude distribution will not be obtained and the antenna characteristics will deteriorate.

Therefore, it is necessary to suppress variations in the active module to a small extent, which poses problems in terms of manufacturing and cost.

The present invention was made to solve the above-mentioned problems, and its purpose is to obtain a desired amplitude distribution even if the variations in the modules are large.

[Means for solving problems]

The antenna adjustment method according to the present invention compares a distribution obtained by projecting the sum of the amplitudes of modules in each row and each column with a reference distribution, rearranges the modules, and arranges the modules that minimize the difference. It's something that allows you to decide.

[Effect]

The antenna adjustment method according to the present invention rearranges the active modules so that the difference from the reference amplitude distribution becomes small, so that it is possible to approximate the desired amplitude distribution. Therefore, desired antenna characteristics can be obtained.

[Embodiments of the invention]

An embodiment of the present invention will be described below.

FIG. 1 is a diagram illustrating a method for rearranging rolls according to an embodiment of the present invention. In Figure 1, xl is the antenna's
One row perpendicular to the axis, Yl and Yl are elements in two columns 71 and 72, respectively, perpendicular to the Y axis of the antenna. In the first part, the lower figure shows each row, each column and the arrangement of the elements of the antenna, and the first figure (-
1 is an amplitude distribution obtained by projecting each antenna row in FIG. 1 (1) onto the Y axis. Furthermore, the solid line in FIG. 9 is the amplitude distribution that has changed due to variations in the active module, and the broken line is the reference distribution. As shown in Figure 1, yI
If Yl is lower than the reference distribution in the column (and Yl is higher than the reference distribution, select the active module y1 with a small amplitude in the YI column and the active module y2 with a large amplitude in the Yl column and replace them to get closer to the reference distribution. The outline of this adjustment method is to bring the overall distribution closer to the reference distribution by repeating this procedure 9 times for each column and row.

Here, the above steps are summarized as follows.

(1) Parameters for Nagisa's initial arrangement are expressed as follows.

Number of X rows Number of Y columns J Motoko's Respect N Deviation from the average of each element An = “n a.

12) The sum of m@An of the first element in the X row is expressed by rl, and the sum of squares is expressed by.

Select two rows in the order of +a+I rll and rearrange the elements so that R is the smallest. Return this move +1i to get the minimum value.

(4) Next, the phase of the amplitude An of the j-th element in the Y column is S, 1
and its sum of squares is expressed as .

Select two columns in the order of t51 Is and 11, and without changing R (search for a pair of elements that minimizes S and rearrange them) - Repeat this procedure until the date is minimized.

In this way, an amplitude distribution close to the standard can be obtained.

Desired antenna characteristics can be achieved.

The results of this simulation are shown in FIGS. 2 and 3. FIG. 2 shows the deviation from the standard distribution in each row of X rows, with respect to A in the initial arrangement and mouth in the rearranged case. FIG. 3 shows the side rope levels for the standard distribution case A, the initial arrangement case B, and the rearranged case O. The horizontal axis is the number of elements. As shown in Figure 2, by rearranging K, the deviation can be kept very small, and in this simulation it overlaps with the horizontal axis. As shown in FIG. 3, the side lobe level is poor if the initial arrangement B remains as it is, but by rearranging the arrangement K, as shown in ma, a side lobe level equivalent to that of A can be achieved in the case of the standard distribution.

Note that in the above embodiment, there are two elements, one for transmitting and receiving and the other for non-transmission.
We have discussed the case of a Kameko scanning antenna with different types.
It goes without saying that even in the case of an electronic scanning antenna in which there are two or more types of amplitude ratios of transmitting/receiving elements, the same procedure can be performed for each amplitude ratio.

〔Effect of the invention〕

As described above, according to the present invention, even if the variations in the modules are large, the antenna characteristics can be improved by rearranging the modules, so that the module can be manufactured easily and at low cost.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the procedure of an embodiment of the present invention. FIG. 2 is a diagram showing deviations in amplitude distribution when simulated using the method of the present invention, and FIG. 3 is a diagram showing changes in sidelobe levels when simulated using the present invention.
FIG. 4 is a diagram showing the number of grooves of a conventional electronic scanning antenna, FIG. 5 is a diagram showing the configuration of an active module, FIG. 6 is a diagram showing a thinning state, and FIG. 1 is a diagram showing an amplitude distribution. In the figure, xl is the row e perpendicular to the X axis of the antenna.
Yj and Y2 d columns orthogonal to the Y axis of the antenna, 7
1 and 72 are two-element antennas a1 to an in their respective columns, b1 to bn are active modules, C is a power distribution/synthesis circuit, d is a duplexer, and e is a transmitter. In the receiver, 1g is the control circuit, and h is the cooling connection. 1 is a control signal distribution circuit, jFi frame, A1 to A
N is element antenna, B1~BNd active module, ! 1 to Jl are power supply lines, (1) is a transmission/reception switch,
(2) is a high output amplifier, (3) is a low noise amplifier, (4)
ke phase shifter. (5ri indicates a control signal line, and (5b) indicates a microwave transmission line. In addition, the same or equivalent parts in Figure 9 are indicated with the same reference numerals.

Claims (1)

[Claims] A plurality of element antennas, a module corresponding to each of these element antennas and composed of a phase shifter, a high-output amplifier, a low-noise amplifier, a transmission/reception switch, etc., a transceiver, and a combination of the above module and the transceiver. In an antenna adjustment method that adjusts the arrangement of the modules with a power distribution/synthesis circuit interposed between them, the distribution of the projected sum of the amplitudes of the modules in each row and each column is compared with the reference distribution, and the distribution of the modules is determined. An antenna adjustment method characterized by rearranging modules and adjusting the arrangement so that the difference between them is minimized.