Optical phase-based beamformer using MZM SSB modulation combined with crystal polarization optics and a spatial light modulator

摘要

The performance of a widely tunable phase-based beamformer for phased array antennas using a new technique to cross-polarized the carrier and the sideband, in order to allow the phase control by means of a spatial light modulator, is experimentally demonstrated. The technique relies on the combination of single sideband amplitude modulation (SSB) using a Mach-Zehnder modulator (MZM) and birefringence (to cross-polarized the carrier and the sideband). The architecture has the potential of controlling multiple independent beams simultaneously. The beamformer feeds an eight elements array showing an insertion loss and a reset speed of around 12 dB and 70 ins, respectively. Far-field antenna patterns between 7.5 GHz and 8.5 GHz for nine elevation angles within a range of +/- 20 degrees have been measured showing beam steering capability, amplitude distribution weighting as well as multibeam operation. (c) 2007 Elsevier B.V. All rights reserved.