This standard is applicable to the environmental factors considered in antenna testing. SJ 2534.15-1987 Antenna Test Method Environmental Factors SJ2534.15-1987 Standard download decompression password: www.bzxz.net
This standard is applicable to the environmental factors considered in antenna testing.
Some standard content:
Standard of the Ministry of Electronics Industry of the People's Republic of China Antenna Test Method Environmental Factors This standard applies to the consideration of environmental factors in off-line testing. 1 Overview SJ2534.15-87 The electrical characteristics of antennas are related to environmental conditions, many of which have special properties and it is not practical to include them all in the test. When testing antennas, environmental factors that have a significant impact on the electrical characteristics of the antenna should be considered as much as possible. This standard only briefly mentions a few cases. 2 Environmental Factors that Indirectly Affect the Electrical Characteristics of Antennas Such environmental factors directly affect the material properties or structure of the antenna and indirectly affect the electrical characteristics of the antenna. Wind and ice affect the mechanical load of the antenna structure. This is a common and important effect that is usually considered in many antenna tests. In order to confirm that the antenna can maintain its structural integrity when subjected to severe acceleration, vibration and impact tests are usually performed and the dynamic deformation is determined to be within the allowable electrical index limits. Antennas placed in the open air are usually equipped with lightning protection and anti-icing equipment, and the impact of such equipment on the electrical characteristics should be estimated. Different natural or man-made environments may impose special requirements. For example, ship-borne antennas must withstand the impact of water waves and the erosion of salt water; antennas on hypersonic rockets should withstand high temperatures and pressures; antennas designed for satellites or sounding rockets should withstand strong ionizing radiation, high vacuum and extreme temperature conditions: antennas operating on the ground near nuclear explosion areas should be able to maintain basic performance under seismic waves, atmospheric shock waves, thermal radiation, ionizing radiation, corrosion by explosion products and radioactive waste. For some cases, special attention should be paid to the changes in various conditions in the natural environment when testing antennas. For example, fast scanning antennas using ferrite elements are particularly sensitive to changes in ambient temperature. Some systems require antennas to maintain extremely low intermodulation distortion, and nonlinear corrosive films can have a significant impact at this time. For precision angle tracking antennas, deviations caused by uneven heating of the antenna by the sun alone may cause pointing errors. For large antennas that rotate in the elevation plane, the electrical characteristics vary with the elevation angle because the deformation of the antenna's own weight varies with the elevation angle. 3 Factors that directly affect the electrical characteristics of antennas Environmental factors that directly affect the electrical characteristics of antennas can be divided into permanent electrical environments and transient electrical environments. 3.1 Permanent electrical environment Issued by the Ministry of Electronics Industry on January 6, 1987wwW.bzxz.Net Implemented on June 1, 1987 SJ2534.15-87 For permanent electrical environments, they have been considered as an integral part of the antenna during design. For example, when designing ground antennas, shipborne antennas, and airborne or space antennas, the effects of the earth, the superstructure of the hull, and the vehicle should be considered respectively. The test methods under these environmental conditions are carried out in accordance with SJ2534.5-5 "Special Measurement Methods" and SJ2534.7-86 "Field Measurement of Amplitude Patterns". Another example is the noise environment of the antenna, including galactic radiation, atmospheric thermal radiation, atmospheric and man-made electrostatic interference, and the thermal radiation of the earth. An extreme example of the effect of a permanent electrical environment on the electrical characteristics of an antenna is a low frequency antenna operating underground or below the surface of the sea.3 Transient Electrical Environment In many cases the electrical environment of an antenna is transient and causes problems of an elusive nature. Moisture mixed with impurities can form a conductive path, which is particularly harmful in areas of strong electric fields. When pure water forms a continuous film, it affects the performance of microwave antennas due to its high dielectric constant. Ice and snow are also factors that directly affect antenna performance. For missile antennas, ionized gases may be present in the exhaust gas or formed when the rocket passes through the atmosphere at high speed. These gases are also part of the electrical environment: Finally, some antennas may be subject to static interference from raindrops, which is a series of noise pulses generated when charged particles (such as raindrops) discharge on the antenna. 4 Special Types of Antenna Environments An antenna stack is a device that is usually used to protect the antenna from the influence of the natural environment. It is an electrical environment that cannot be ignored. Additional Notes This standard was proposed by the Standardization Institute of the Ministry of Electronics Industry. This standard was drafted by the 39th Institute of the Ministry of Electronics Industry. The main drafter of this standard is Ke Shuren. Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.