How is antenna OTA testing performed?

　　1. Currently, there are two main methods for determining antenna radiation performance.

　　1. Passive testing:

　　Determining antenna radiation performance is defined as a standard antenna test, also commonly referred to as passive testing. Passive testing focuses on evaluating antenna radiation performance based on parameters such as gain, efficiency, and radiation pattern. Commonly used test parameters include:

　　Return Loss; Directivity; Gain, dBi (dBd)

　　Efficiency; Radiation Pattern

　　Effective Isotropic Radiated Power (Gain + Transmitted Power)

　　Input Impedance (antenna interface impedance test)

　　VSWR, RL (antenna standing wave ratio, return loss test); 3D (3D field strength pattern)

　　3dB BW, FB Ratio (beamwidth, front-to-back ratio)

　　Cross polar, Isolation

　　Directivity; Efficiency

　　2. Active Test:

　　This test measures the radiated power and receiving sensitivity of an antenna in a designated microwave anechoic chamber, also known as the active test. Active testing mainly focuses on the overall radiation power and receiving sensitivity of the antenna, namely TRP and TIS. This method can better reflect the overall radiation performance of the antenna. OTA active test parameters:

　　TRP (total radiated power); TIS (total receiving sensitivity); RS (receiving sensitivity determination relative to the reference channel)

　　SS (sensitivity scan); EIRP (equivalent isotropic radiated power); EIS (equivalent isotropic receiving sensitivity)

　　II. TRP (total radiated power) and TIS (total receiving sensitivity) test methods and requirements.

　　1. TRP test requirements

　　(1) EUT is at maximum power transmission;

　　(2) Non-portable EUT needs to be tested in free space;

　　(3) Portable EUT also needs to be tested under human head model conditions;

　　(4) In each frequency band supported by the EUT, test the three channels of high, medium and low;

　　(5) For EUT with retractable antenna, it needs to be tested under two conditions.