JPS5912623Y2 - Power supply device with reference polarization generation mechanism - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a power feeding device equipped with a mechanism for generating polarized waves as a reference necessary for measuring polarization characteristics of an antenna device with high accuracy.

When measuring the polarization characteristics of an antenna device (tilt angle (inclination angle of the long axis of polarization) and elliptical polarization coefficient), the reference polarization must be supplied to the antenna device under test by some method. There is a need.

Conventionally, as a means for supplying this reference polarized wave, as shown in FIG.
A method of receiving this signal with an antenna device under test has been widely used.

A measurement system for polarization characteristics of an antenna device using such means will be explained.

In FIG. 1, 1 is a so-called collimation device, including a radio frequency signal oscillator 2, a polarization converter 3, and an athena 4.
It is structured as follows.

5 is an antenna device to be measured, which includes an antenna 6, a power supply device 7, and a terminal 8 for connecting a radio device such as a transmitter or a receiver.
, 9.

Reference numeral 10 denotes a polarization characteristic measuring device, which detects the amplitude ratio and phase difference of radio frequency signals (hereinafter simply referred to as signals) outputted to terminals 8 and 9, and measures the polarization characteristics.

Next, the operation of this measurement system will be explained.

When the antenna device under test 5 receives a signal sent from the collimation device 1, terminals 8 and 9 receive an amplitude ratio and a phase difference determined by the combination or characteristics of the polarization characteristics of the collimation device 1 and the antenna device under test 5. A signal with .

Therefore, by detecting this amplitude ratio and phase difference with the polarization characteristic measuring device 10, the combined polarization characteristics of the collimation device 1 and the antenna device under test 5 can be measured.

This measurement method utilizes the fact that the phase difference φ and amplitude ratio m, J, and θ between the two signals obtained at terminals 8 and 9 are expressed by the following equations.

? Here, j corresponds to the elliptical polarization factor of the antenna device under test 5, and error θ is the inclination angle of the polarization plane of the signal with respect to the horizontal direction.

Measurement is performed as follows.

If the antenna device 5 to be measured is a circularly polarized antenna device, first, a linearly polarized signal tilted by a known angle θ from the horizontal plane is sent out from the collimation device 1, received by the antenna device 5 to be measured, and then sent to the terminals 8, Determine the amplitude ratio m' and phase difference φ' of the two signals obtained in step 9, and use equation (1). (2)
Compare with m and φ.

If this is deviated, m' and φ' are adjusted to correct the measurement system to the standard state.

After a calibration of more than 1''', the signal from the collimation device 1 is changed into a completely circularly polarized signal and sent out. measure degree.

The elliptical polarization coefficient ep and tilt angle τ of the antenna to be measured are determined by the following equations.

ep= 17.87 x 1G (dB)
---(3) l τ =-(Φ+90) (degrees) ... (4) 2 Since the above calibration method is used in the conventional polarization characteristic measurement method, the polarization characteristics of the collimation equipment are We needed a function that could change the function.

Furthermore, if the antenna to be measured has a large aperture diameter, it is necessary to make the distance between the collimation and the antenna to be measured sufficiently large.

child? Therefore, in order to measure the polarization characteristics of earth station antennas for satellite communications in recent years, it is often difficult to secure a location for collimation, and a satellite is often used instead of the collimation device 1.

At this time, it was impossible to change the polarization characteristics of the satellite as described above, and the problem was how to calibrate the polarization characteristics.

This idea was made in order to eliminate the drawbacks of the conventional ones as described above. A reference polarization detection terminal is installed on the feeding device of the antenna under test, and the reference polarization signal is fed from this, and the collimator It is an object of the present invention to provide a means for supplying a predetermined reference polarized wave required for measuring polarization characteristics with high accuracy without changing the polarization characteristics of the device.

An embodiment of this invention will be described below with reference to the drawings.

In FIG. 2, 11 is a polarization converter, 12 is a reference polarization coupler having a terminal 15 capable of detecting the reference polarization, and 13 is a polarization splitter.

The reference polarization coupler 12 includes a polarization converter 11 and a polarization splitter 1.
The radio wave transmission axis between the two can be rotated, and it has a mechanism that allows the angle of rotation to be read accurately.

14 is an oscillator.

The signal applied to the terminal 15 is adapted to be excited into the reference polarization coupler 12 with linear polarization.

This linearly polarized wave is excited and the signal is input to the polarization splitter 13 with an electric field E tilted by φ as shown in Fig. is terminal 8: EX
, terminal 9: Ey.

Here, the amplitude ratio of Ex and Ey is Ey/Ex
= tan l (s).

Note that Ex and Ey are in phase, and φ is the reference polarization coupler 1.
This is the rotation angle of the radio wave transmission axis in 2.

Therefore, by reading the rotation angle in the reference polarization coupler 12, a known reference signal that is in phase and whose amplitude ratio is determined by equation (1) can be obtained at the terminals 8 and 9.

In other words, the calibration of the relationship between the phase and amplitude of the terminals 8 and 9, which was conventionally carried out using transmitted waves from a collimation device, can be carried out by the antenna device under test itself.

In this case, if only a calibration value of a specific elliptical polarization factor is required, the above rotation mechanism is not necessary.

After performing the above calibration, the polarization characteristics are measured using the signal from the collimation device as in the conventional case.

FIG. 3 is another embodiment of the invention which allows the calibration method of FIG. 2 to be carried out more accurately.

In the figure, 16 is a variable attenuator, 17 is a variable phase shifter, 1
8 is a radio frequency amplifier; 19 is a reference polarization coupler;
Although it may be of the same mechanism and function as the reference polarization coupler 12 shown in the figure, in this method, the structure that can be excited with a fixed polarized wave with φ of 45° as shown in Fig. 4 can be most accurately calibrated, so the following method is used. In the description, when the reference polarization coupler 19 is installed so that the polarization angle is 1245 degrees, the input wave to the terminal 15 is split into terminals 8 and 9 as signals having the same phase and the same amplitude.

The signal at the terminal 8 is amplified by the amplifier 18 and then applied to the polarization characteristic measuring device 10 .

The signal at the terminal 9 is amplified by a radio frequency amplifier 18 and then applied to the polarization characteristic measuring device 1o via a variable attenuator 16 and a variable phase shifter 17.

The attenuation amount of the variable attenuator 16 is α (dB), and the variable phase shifter 17
If the phase amount of is θ (degrees), then the reference polarization for calibration is tilt angle [degrees] = 466 + # (Since it can be calculated using the relational expression n, the value of the polarization characteristic determined from α and θ is correcting α and θ so that they match the values of the polarization characteristics of the reference polarization signal applied from the reference polarization coupler 19;
Calibration is performed by

An example of the structure of the reference polarization couplers 12 and 19 having the reference polarization detection terminal 15 is shown in FIG.

What about the same figure? The mode coupler is a directional coupler type, and 20 is a circular waveguide, 21 is a coupling hole, and 22 is a rectangular waveguide.

The signal wave inputted from the terminal 15 passes through the reference polarization coupler 19 and excites direct polarization in the TH1 mode, which is the fundamental mode of the circular waveguide, to the polarization splitter 13 side.

In FIG. 3, the means for changing the attenuation amount α and the phase amount θ is not limited to the variable attenuator 16 and the variable phase shifter 17, but may be an attenuator and a phase shifter provided in the polarization characteristic measuring device 10. It can also change depending on the device.

In the above embodiment, the case where the calibration signal is input to the terminal 15 has been described, but it is also possible to arrange the oscillator at the polarization characteristic measuring device 10 and the polarization characteristic measuring device at the oscillator 14. However, it is possible to obtain a polarization reference signal.

In this case, it is necessary to modulate only the signal wave input to the terminal 8 after dividing the oscillator output into two, and to provide the polarization characteristic measuring device with a function to demodulate this.

In addition, as the reference polarization coupler 12 or 19, it is possible to realize a configuration in which circularly polarized waves are excited by simply changing the calculation formula, but the structure of the reference polarization coupler becomes complicated and the ideal circular polarization is not achieved. This method has drawbacks such as the fact that the error in the calibration value is larger than that of the present method due to the difficulty in controlling the waves, making it impractical.

As described above, according to this invention, the antenna feeding device is configured to have a reference polarization generation function, so when measuring the polarization characteristics of the antenna device, it is necessary to change the polarization plane on the collimator side. This has the effect of making it possible to measure polarization characteristics with high precision.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a measuring device including a conventional reference polarization control means, Fig. 2 is a block diagram of a power supply device with a reference polarization generating mechanism according to an embodiment of this invention, and Fig. 3 is a block diagram of a power supply device with a reference polarization generating mechanism according to an embodiment of this invention. A block diagram of a power supply device with a reference polarization generating mechanism according to another embodiment, FIG. 4 is an explanatory diagram showing the operation of a polarization splitter, and FIG. 5 is a structure of a reference polarization coupler used in the device according to this invention. It is a perspective view showing an example. In the figure, 12.19...Reference polarization coupler,
13... Polarization splitter, 8, 9... Connection terminal to transmitter/receiver, 15... Reference polarization detection terminal. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (3)

[Scope of utility model registration request] (1) An input terminal, a polarization converter that performs a predetermined polarization conversion on a passing signal fed through the input terminal, and a polarization converter that polarizes and separates the passing signal from the polarization converter. a pair of output terminals that guide the polarization splitter output signal to the outside, and a main circuit arranged between the polarization converter and the polarization splitter or between the manual terminal and the polarization converter, A reference polarization coupler having a reference polarization signal terminal capable of feeding a reference polarization signal of linear polarization having a predetermined transmission angle to this main circuit, A power supply device with a reference polarization generating mechanism, characterized in that it is capable of performing demultiplexing and generating a calibration signal corresponding to the reference polarization signal at the pair of output terminals. (2) The reference polarization coupler is equipped with a mechanism that can vary the transmission axis of the reference polarization signal, and by changing the transmission axis of the reference polarization signal, the reference polarization signal is equivalently supplied to the reference polarization signal terminal. A power supply device with a reference polarized wave generating mechanism according to claim 1 of the above-mentioned utility model registration, characterized in that the polarization characteristic of a wave signal is changed. (3) A variable attenuator and a variable phase shifter are provided on one or both of the two transmission lines arranged between the polarization splitter and the pair of output terminals, and the attenuation characteristics and phase characteristics of the two transmission lines are provided. The above-mentioned utility model registration is characterized in that the polarization characteristics of the reference polarization signal that is equivalently fed to the reference polarization signal terminal are changed by changing the characteristics to have a difference in characteristics. A power supply device with a reference polarization generation mechanism according to claim 1.