GB 12191-1990 Test method for crack antenna pattern of marine navigation radar GB12191-1990 standard download decompression password: www.bzxz.net

UDC621.396.677.5:621.96
National Standard of the People's Republic of China
GB 12191—90
Slotted-wavcguide antenna for marinc radar
Test methods of radiation pattern ofthe slotted-wavcguide antenna for marinc radarPublished on 1990-02-01
State Administration of Technical Supervision
Implemented on 1990-08-01
W.National Standard of the People's Republic of China
Slotted-wavcguide antenna for marinc radar
Test methods of radiation pattern ofthe slotted-wavcguide antenna for marinc radar1Subject content and scope of application
GE 12191—90
This standard specifies the method for testing the amplitude radiation pattern (hereinafter referred to as the horizontal pattern) of the ship navigation antenna (hereinafter referred to as the antenna) in the antenna test field.
This standard is applicable to the inspection of ship navigation antenna. 2 Terminology
2.1 Antenna horizontal pattern
The direction of the maximum value of the antenna's main radiation pattern is in a plane of 90°, and the antenna's rotation axis coincides with the Z axis (that is, the 6-direction). The pattern in a plane of 90° is called the horizontal plane pattern. The coordinate system is shown in Figure 1. Figure 1 Antenna coordinate system
2.2 The vertical line is perpendicular to the square figure
The antenna coordinate system is arranged as in Article 2.1, then the directional diagram in the plane passing through the two axes and the vertical line in the direction of the maximum value is called the vertical directional diagram,
2.3 Cross-polarization division
When using waveguide slot antenna to radiate horizontally polarized electromagnetic waves, if the waveguide narrow side is slotted, when the slot and the vertical line of the waveguide wide side have an angle, cross-polarization division will occur, which is cross-polarization division. Approved by the State Technical Supervision Commission on February 1, 1990
Implementation on August 1, 1990
W.3 Antenna test field requirements
GB12191-90
3.1 Different types of test fields can be selected according to the requirements. In most cases, an elevated test field in a space test field is selected. Mountains and tall buildings can be used to replace antenna towers and erect antennas. 3.2 The distance R between the test antenna and the source antenna is: R
(diameter of the test antenna;
)——diameter of the source antenna,
——wavelength of the space,
3.3 The highest level of the clutter reflection signal and the clutter signal from other sources shall not exceed 40 dB of the signal from the source antenna to the test antenna in a straight line path,
3.4 ​​The ground reflection energy can be reduced by adding a diffraction grating or other methods to meet the test requirements. 4 Antenna test equipment
4.1 Antenna test method
The block diagram of a typical antenna test system is shown in Figure 2. The required test equipment can be determined according to the conditions and test content. It can be recorded automatically by using an automatic wave recorder as shown in Figure 2a: It can also be recorded point by point by using a detector and a test amplifier instead of a receiver as shown in Figure 2b. 4.2 Commonly used instruments and equipment
4.2.1 Source antenna
The source antenna can be a trumpet or parabola antenna, and its aperture size must meet the requirements of Article 3.2 and can radiate the required polarized electromagnetic field within the following operating frequency range:
4.2.2 Signal source
Various forms of signal sources can be used, such as solid-state oscillators or magnetron oscillators. The power stability is required to be within ±0.1dB within the measurement time, and the frequency stability is better than 10". According to the test requirements, the signal source should be equipped with various internal and external modulation functions. 4.2.3 The gain stability of the receiver is better than +0.1 dB within the measurement time. The dynamic range is greater than 40 dB. 4.2.4 Measuring amplifier The gain stability of the measuring amplifier is better than ±2% during measurement. 4.2.5 Crystal detector At the operating frequency 1, the voltage standing wave ratio is less than 1.1. 4.2.6 Precision attenuator The maximum attenuation of the precision attenuator is greater than 35 dB, and the attenuator accuracy is 0.2 per 10 dB. If one is not enough, two may be used. 4.2.7 Antenna output angle error is 1+1. 4.2.8 Automatic lobe recorder dynamic range is greater than or equal to 10° and can record antenna pattern in the required manner. 2. W. bzsoso: com receiver transfer element detector 5 Directional pattern test 5.1 Large line test field Test antenna Test positioner Control plan Directional pattern recorder
GB12191-90
Dispersed positioning
Test location
Indicator
Source tower indicator
Automatic reduction recorder test method
Source antenna
Forging room
Test daywww.bzxz.net
Digital tester
Customized device control
Test start position
Indicator
bPoint by point test method
Yanmao extension indicator
Figure 2 Block diagram of large line test system
Select the appropriate wireless antenna according to the antenna under test in Chapter 3 Test field. 5.2 Test method
According to the conditions of the instrument and equipment, select a test method according to Figure 2. 5.3 Installation of the test antenna
When installing the test antenna, the coordinate system of the test antenna must coincide with the calibration system of the locator. 5.4 Alignment of the test antenna and the source antenna
Source tower control
Strategy control
W.GB1219190
5.4.1 Take the test antenna and the source antenna connection line as the incident direction of the electromagnetic wave radiated by the source antenna, adjust the position of the source antenna, so that the source antenna radiates the required polarized electromagnetic wave, and the source antenna beam pointing should be 5.4.2 When testing the horizontal plane pattern or vertical pattern, adjust the positioner of the tested antenna so that the beam of the tested antenna is pointed at the source antenna. When the pattern on a specific plane is required, the positioner of the tested antenna can be adjusted to the specified position according to the requirements. The signal drop caused by the misalignment of the beam fingers should not exceed ±0.1dB. 5.5 Recording of data
5.5.1 Take the maximum value of the main register as the reference level and set it to 0dB 5.5.2 When recording the test point by point, for the horizontal pattern, the data of specific points such as the half-power point, -20B point, and the maximum value of the secondary avoidance must be recorded. For the vertical pattern, the data of specific points such as the half-power point must be recorded. 5.5.3 When recording with a wave recorder, attention should be paid to the dynamic range of the system. The dynamic range should be greater than or equal to 5dB than the actual required range to ensure the completeness of the graph. The angle grid size should be selected according to the different test antenna sizes to ensure the recording accuracy. 5.6 Cross-polarization measurement
5.6. Some waveguide cracks will produce cross-polarization components. When it is required to test the cross-polarization components of the horizontal south pattern, the polarization direction of the source line must be changed to $0° after measuring the horizontal pattern (the source line beam pointing direction remains unchanged) to measure the size of the cross-polarization component relative to the maximum value of the main lobe, and record it in the horizontal pattern. 5.6.2 When testing the vertical plane pattern, if the ground energy reflection is too strong, the test antenna and the source antenna can be rotated 90 degrees around the vertical axis, and then the pattern can be tested.
5.7 Requirements for drawing typical antenna patterns
Typical antenna patterns must indicate the half-power point, 20B point, maximum value of the clipping lobe, etc., and must also be accompanied by the antenna design, test date, test location, main instruments used and working frequency. Additional notes:
The standard was proposed by the Ministry of Machinery and Electronics Industry
The standard was drafted by Shanghai Marine Navigation and Control Research Institute and Shanghai Radio Factory No. 4. This standard is mainly drafted by the people.
W.bzsoso.cOm
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