Abstract: Described are ice shields and methods for protecting tower-mounted equipment. An ice shield assembly can include an ice shield. The ice shield can include a base, a blade structure attached to the base, at least one support member on each side of the blade structure attached on a first end to the blade structure and on a second end to the base, and a beam attached to at least one of the base, the blade structure, and the support members. The ice shield assembly can include a mounting bracket engaged with the beam that can permit vertical translation of the ice shield with respect to the mounting bracket. The ice shield can include a shock absorber configured to arrest relative motion between the ice shield and the mounting bracket by dissipating kinetic energy in the ice shield assembly.

Abstract: Disclosed herein is an interferometric-based materials analysis system (10) that employs a novel combination of laser beam shaping and pointing techniques, the use of a low cost, rugged, and compact diode laser (22) as a detection laser, and the use of signal processing techniques that compensate for inherent instabilities and short-term drift in the diode laser. A matched filter processing technique is disclosed for processing interferometrically-obtained data points from a target being analyzed. The matched filter technique is shown to be especially useful for detecting and analyzing Lamb modes within thin targets, such as a silicon wafer undergoing a rapid thermal processing cycle. Also disclosed is a method and apparatus for interferometrically monitoring a target to determine, in accordance with predetermined criteria, an occurrence of a period of time that is optimum for obtaining a data point.