The introduction of new technology 5g introduces large-scale MIMO, millimeter wave and other new technologies. The traditional test technology for 4G system performance and RF performance cannot support 5g test requirements. First, there are a large number of large-scale MIMO ports. If all the MIMO ports are connected by cables, the test efficiency will be low and the cost will be expensive. Second, the attenuation of the millimeter wave band RF connection port is very serious, and the millimeter wave base station and terminal equipment cancel the RF connection interface. The traditional conduction test method based on RF connection fails. In order to promote the technical research and equipment development of 5g base station, terminal and chip, the OTA based new system test method has become the only feasible test scheme for 5g millimeter wave.
The test system adopts compact field technology, uses high-precision hyperbolic paraboloid reflector to reflect the signal from the feed antenna, and forms a plane wave in the test area to test the radiation performance. Due to the high frequency, fast phase change and large free space loss of millimeter wave, compared with the traditional far-field test system, the static zone of compact field has smaller amplitude phase deviation, smaller space loss and smaller size.
Using compact field technology, the system works with base station emulator, spectrum analyzer, signal source and terminal device to complete radio frequency consistency test items defined by 3GPP 38521-2.