Electrical/​Electronics

Advances in time gating of ultrasonic signals in scanning acoustic microscopes have been proposed to enable detailed nondestructive examination of bonds and other interfaces deep within the interiors of such micromachined objects as high-density integrated electronic circuits and...

An automatic tunneling-controlled, micromachined Golay cell has been implemented in a multichip integrated-circuit module. The module is designed specifically for sensing infrared radiation indicative of the concentration of glucose in blood, but its low noise, high gain, and low power...

In a proposed modification of the basic design of a Michelson interferometer, the beam aperture would be split into a number (N ≧ 2) of smaller areas and the optics arranged so that the beam in each area would generate a distinct segment of the overall desired interferogram. Each segment of the...

Two improvements have been made to solve two problems that arise in conjunction with a fabrication process in which an HgCdTe photodetector is mounted on an alumina substrate with epoxy. Although most of the HgCdTe-photodetector industry has abandoned this process in favor of epitaxial...

The Wallops Flight Facility of the Goddard Space Flight Center has designed and built in-house a Mobile Range Control System (MRCS), which is a self-contained system to be deployed in support of rocket launches at remote ranges in cases in which termination of flight may be required for...

The split-geometry design for arrays of photoconductive HgCdTe infrared photodetectors described in the preceding article can also be used to mitigate the deleterious effect of a phenomenon called "sweepout," which degrades performance. Sweepout occurs in conventional small HgCdTe...

Focal-plane arrays of HgCdTe photoconductors have been designed and fabricated to satisfy special requirements for high-performance long-wavelength infrared (LWIR) photodetectors. The special requirements are the following:

A report describes a study of nominal-performance (H2), robust-performance (μ-synthesis), and mixed H2/μ methods for designing fixed-order controllers applied to an active-tendon control system for suppressing seismic vibrations in a structure. The study involves an application of...