Primary standards for antenna factor calibration in the frequency range of (30 to 1000) MHz

We have built a set of precision dipoles to be used as primary standards for antenna calibration. In order to evaluate and verify the performance of these dipoles we have made site attenuation measurements on our open-area test site and in the anechoic chamber. The comparison of insertion loss data calculated using Numerical Electromagnetic Code (NEC) and measured values yielded deviations of less than 0.3 dB for any measurement and less than 0.25 dB for the mean values of repeated measurements at each frequency. The uncertainty in the transmission loss measurement was 0.11 dB for a confidence level of 95.5%. The combined, expanded uncertainty in the antenna factor of one precision dipole is 0.15 dB.