Estimate the measurement uncertainty of broadband antenna (30MHz to 1GHz) calibration system

According to CISPR 16-1 & ANSI C 63.4 standard requirements, to implement EMI radiated emission measurement needs to use accuracy antenna factor (AF). The Standard Site Method(SSM) of antenna calibration is most popular technology in the EMI sector. In Taiwan, the SSM calibration technology is also to set up in BSMI WUDA Antenna Site to calibrate broadband antennas (30MHz to 1GHz). This paper will simply describe the theme of antenna calibration, introduce the structure of this calibration site and describe the measures used to control its calibration uncertainty below 1 dB.