Showing papers on "High dynamic range published in 1980"

Broadband superheterodyne tracking circuits for millimeter‐wave measurements

Abstract: Superheterodyne stimulus‐response measurements can be made with high dynamic range, but are often sensitive to oscillator frequency drift and noise. The usual techniques for reducing this sensitivity often become impractical at millimeter‐wave frequencies and above. This paper describes a feedforward tracking technique and its application to single frequency millimeter‐wave interferometry and Doppler‐shift scattering measurements on tokamak plasmas. Swept frequency transmission measurements can also be made with high dynamic range using this technique.

Astronomical Imagery with Solid-State Arrays

Abstract: Publisher Summary This chapter discusses optoelectronic characteristics and astronomical applications of two panoramic solid state imaging arrays: a 50 x 50 photodiode array and a 400x400 charge coupled device (CCD) The 50 X 50 photodiode array plus associated electronics and software were assembled as part of the requirements for a PhD dissertation This system has been used quite successfully in observations of the nuclear regions of nearby galaxies, an observational area for which high dynamic range and signal to noise ratio are required, and for which there is no shortage of light The array used in this chapter work contains a number of defects, including dead columns and pixels, “hot” pixels, that is pixels with higher than average dark current rate, and columns prone to streaking Some of these defects were permanent; others were transient, for reasons unknown