Planar near-field measurements of microstrip array antenna using photonic sensor at X band

Planar near-field measurements (PNFM) are widely used as a technique for antenna pattern measurements of directive antennas. However the equipment becomes large and heavy below a few GHz, because the size and the weight increase relating to the wavelength. To overcome the difficulties, we have proposed a photonic sensor as the probe for the PNFM and have shown its usefulness through the measurement of a horn antenna at 8 GHz. In this paper, we also show that the photonic sensor can be used for antenna pattern measurements at 9.41 GHz, of a microstrip array antenna.