Millimetre-wave-imaging system at 95 GHz - quantitative performance evaluation

A quantitative performance evaluation of the millimetre-wave-imaging system developed in the authors´ group is carried out. Two parameters, SNR_I (image signal-to-noise ratio) and NEΔR (noise equivalence reflectivity difference) of a few common test targets, a copper slab, a leather covered copper slab and a Perspex slab are used in the evaluation of image qualities, hence to characterise the performance of such a system. In the calculation of these two parameters, a convenient four-step procedure developed by the authors is used. For the evaluation of the resolution of the millimetre-wave-imaging system, an indirect approach is used, in which the imager point spread function (PSF) is estimated based on the measurement data of a knife edge. From the imager PSF the imager resolution is calculated. All these parameters have quantitative values and can be used to make performance comparisons.