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Optical systems designed for some defense, environmental, and commercial remote-sensing applications must simultaneously have a high dynamic range, high sensitivity, and low noise-equivalent contrast. We have adapted James Janesick's photon transfer technique for characterizing the noise performance of an electron multiplication CCD (EMCCD), and we have developed methods for characterizing performance parameters in a lab environment. We have defined a new figure of merit to complement the traditionally used dynamic range that quantifies the usefulness of EMCCD imagers. We use the results for EMCCDs to predict their performance with hyperspectral and multispectral imaging systems.

A Circuit topology for realizing a BPSK (1 80 degree) modulator without the use of reactive phase determining networks is presented for the first time. This physically small Circuit employs a trio of enhancement mode MESFETs which are uniquely configud to extend the upper frequency response of the design to in excess of 1.7 GHz. This approach is particularly noteworthy as it is implemented using less than 3 V dc and precludes the need for negative gate voltages making it attractive for use in wireless applications.