5G communication

作者： 沃锌科技 时间：2023-11-28 16:12:41 阅读：13

Before 5G, most wireless device testing was conducted using wire methods. This includes testing the modem chipset, RF parameter testing, and complete device functionality and performance verification. The wireless (OTA) testing method is mainly used for antenna performance testing and device multi input multi output (MIMO) performance measurement. The 5G millimeter wave (mmWave) device represents a disruptive shift in the wireless industry, as OTA is the only feasible testing method among all wireless testing cases.

At mmWave frequency, higher path loss and shorter wavelengths require controllable directional antennas (gain) - typically phased array antennas. In addition to traditional LTE and Frequency Range 1 (FR1) monopole antennas, many 5G devices also require multiple sets of mmWave antennas. Due to the fact that the mmWave antenna must be directly connected to the RF front-end (RFFE) amplifier, it is not possible to access and test equipment at lower frequencies, and radiation testing methods are required.

The traditional conducted RF testing method uses high-performance coaxial cables between the measurement solution and the device under test (DUT). OTA replaces the cable with an air link, and the DUT communicates directly with the antenna as part of the testing solution through this link. To ensure a good RF environment (i.e. test transmission lines and eliminate external interference), it is best to manage OTA connections inside the darkroom.