Spherical Near Field Test
The rapid development of antenna and related technology has made higher demands on antenna measurement technology in terms of precision, efficiency and test function. Antenna characteristic parameters are measured in a variety of ways. At present, they fall into three major categories: far field measurement, compact field measurement, and near field measurement. Antenna near field measurement is divided into three categories: planar near field, cylindrical near field, and spherical near field. Among them, the spherical near field is the only feasible method for measuring the three-dimensional radiation performance of full-size antennas at the moment with greatest technical challenges.
The spherical near field antenna testing technology has the following advantages over other testing techniques:
- In the spherical near field measurement, the antenna radiation field can be expressed as a finite term for the superposition of the spherical wave function, and this truncation error is smaller than the measurement error and the calculation error.
- When the spherical near field is measured, the probe points to the antenna under test. The probe compensation can be achieved by software program and measurement system.
- The spherical near field measurement can provide the complete pattern and gain of the antenna under test.
- Measurements are available for a variety of antennas, including narrow beam antennas, wide beam antennas, and omnidirectional antennas.
- The impact of the environmental can be weakened by the use of directional probes and absorbing materials in the system.
Sunyield Technologies Launched SY-180
Sunyield Technologies have focused on research and development of antenna measurement technology over the years, and have released a series of antenna measurement system as SY-16 (M), SY-24(L), SY-64/68, SY-128, and SY-168 in the field of spherical near field testing. In April 2017, Sunyield Technologies have launched the new SY-180 antenna measurement system, which is currently the world’s largest spherical near-field antenna measurement system, and it supports active and passive measurements of large antennas, especially for BTS antenna measurements.
In 5G communication, due to the need for a wider transmission bandwidth, the frequency band used has reached millimeter wave level. The required test site has a distance of up to a few kilometers away, and it is very difficult to achieve such a far test environment in far field testing. Thank to advantages of spherical near field test brought about by its own technical characteristics, the introduction of Sunyield Technologies SY-180 spherical near field antenna measurement system will certainly shine in the future communications technology.