The purpose of OTA testing
The performance of the whole machine is getting more and more attention in the performance test of the mobile phone. This radiation performance reflects the final launch and receive performance of the mobile phone. There are two methods to investigate the radiation performance of the mobile phone: One is to determine the radiation performance of the antenna. Traditional antenna testing method, called passive testing; The other one is in a specific microwave anechoic chamber. Radiation power and receiving sensitivity of the mobile phone，which is Called Over The Air (OTA) testing。
Passive testing focuses on Antenna gain、efficiency、direction chart radiation parameters to investigate the radiation performance of the mobile phone.
Although Passive testing consider the influence of the environment on the performance of antenna(such as antenna around the device, open cover and close cover) ,but cannot be directly informed of the antenna and the whole machine with the final radiation power and receiver sensitivity.
OTA testing is focused on the radiation performance of the mobile phone from the transmitter power and the receiving sensitivity of the mobile phone.OTA testing is transmitting power in the microwave specific test machine in all directions in three-dimensional space and receiving sensitivity. More directly reflect the radiation performance of mobile phone.
CTIA(Cellular Telecommunication andInternet Association)works out OTA(Over TheAir) Standard。OTA testing focus on the performance of the whole machine test, which become the mobile phone manufacturers to pay attention and recognition of the test project.
Only through FTA (FullType Approval) certification test phone models to go on sale. IDuring the FTA test，RF performance test mainly mobile phones in the cable connection mode；Cell phone radiation emission and reception performance machine， FTA test is not clearly defined, OTA test just to make up for the shortage。At the same time, terminal manufacturers must clearly understand the radiation performance of the production of mobile phones. Increase the transmission and reception of cell phone radiation index through various measures. If performance is poor cell phone radiation will cause the phone signal is not good, poor voice quality, easily dropped, which is also the problem of customer complaints.
When the phone call, because the human brain near the phone antenna, the lower transmit and receive performance of mobile phones, mobile phone radiation machine will reduce the transmit and receive performance. In the mobile phone R & D process should measure the quantitative impact of the human brain to transmit and receive performance of mobile phones, and to optimize the design, so that transmit and receive performance degradation is not too large, a reduction of electromagnetic coupling effects of the human body and the antenna.
In order to investigate cell phone radiation, in addition to study the performance of mobile phone antenna passive, active performance of the machine is also an important aspect of the study. The current overall performance more and more terminal manufacturers active attention, and therefore the two should be in the study of radiation properties of mobile phone radiation properties taken together. At present the terminal antenna manufacturers in research and development are generally required antenna suppliers of passive and active test report.