Reduced set of points in phaseless broadband near-field antenna measurement: Effects of noise and mechanical errors

A new method recently developed for planar nearfield broadband phaseless antenna measurement is adapted to work with a reduced set of points. The method is an extrapolation of the conventional off-axis holography in which a frequency sweep is made at each point of the acquisition grid, and the phase is retrieved simultaneously for all the frequencies by filtering the hologram in the time-domain. As the phase is retrieved independently at each acquisition point, non redundant sampling techniques can be applied without the need of increasing the spatial bandwidth of the hologram. The bounds of the error in the far field pattern regarding the effect of mechanical errors and noise are studied by means of Monte Carlo simulations. A measurement example in the Ka band is presented to validate the method.