说明：  有源GPS天线的测试，可以帮助厂家确认GPS天线其的中心频率是否正确，验正增益和方向性等性能指标是否达到设计要求。通过GPS的OTA测试
(Active GPS antenna testing, can help manufacturers to confirm the center frequency of its GPS antenna is correct, validation, performance indicators such as gain and directionality whether the design requirements. Through the GPS-OTA Test)