A Broadband, Isotropic, Real-Time, Electric-Field Sensor (BIRES) Using Resistively Loaded Dipoles for EMI Measurements

A broadband, isotropic, real-time, electric-field sensor (BIRES) developed by the National Bureau of Standards (NBS) consists of three resistively loaded dipoles mounted orthogonally to each other. It has the capability of measuring frequency, polarization, magnitude, and phase information of the incident electromagnetic (EM) field. The typical tangential sensitivity of the SIRES is 13 to 16 μV/m with a typical usable dynamic range of 125 to 144 dB for various bandwidths in the frequency range of 10 MHz to 1 GHz. The isotropic response of the BIRES is obtained by arithmetically calculating the Hermitian magnitude of the incident electric field, and its variation is found to be less than +1 dB.