The Antenna Measurements using the Three-antenna Extrapolation Range

Based on the extrapolation range facility, which was built in National Institute of Metrology (NIM) China, several antenna measurement methods are investigated, including the three-antenna extrapolation method, the commonly used gain-transfer method and the novel reference-antenna method by combining the extrapolation technique. The uncertainties for the measurement results using these methods are investigated. It is demonstrated that by using the extrapolation technique, a reference gain standard with high degree of accuracy is obtained, and it will help reducing the gain uncertainty in other antenna measurement ranges by employing it in the gain-transfer method.