What is a near-field measurement?

2022-05-11 17:54:21      点击:
The measurement of antenna parameters is helpful for us to understand the performance of antenna and apply it more reasonably.


1.  Basic method of near field measurement

At present, in the field of antenna near-field measurement, the commonly used antenna measurement methods include plane scanning, cylindrical scanning and spherical scanning. These methods need to collect data on plane, cylindrical and spherical respectively.

2.  Characteristics of near field measurement method
Planar near-field scanning requires smaller darkroom environment, simpler adjustment technology and mathematical analysis. This technology is suitable for high directivity antenna measurement, such as butterfly or phased array. Almost all received or transmitted energy passes through the plane scanning area. However, the plane near-field only covers a limited area of the antenna pattern to be measured, so it is difficult to measure the directivity of the antenna.

Cylindrical near-field scanning is suitable for sector beam antenna measurement. Its energy is concentrated in one axis and dispersed in the other orthogonal axis. For example, the radiation pattern of mobile phone base station antenna is mostly limited to a small range in the pitch direction.

Spherical near-field scanning can be used for the measurement of any antenna, especially for omnidirectional or approximate omnidirectional antennas that are not suitable for plane and cylindrical measurement. This method has no truncation of the measurement surface, so it can be used to accurately measure the far sidelobe of any type of antenna.
请添加微信