Abstract: A broadband adaptive Doppler estimator and canceller is described for adaptively removing a moving source of near field primary interference that is masking a weaker target. The estimator and canceller employs a distributed field of sensors, through which is moving the source of interference. The estimator and canceller takes the form of a canceller system, wherein the measured reference waveform is a Doppler shifted version of the interference. The estimator and canceller employ interpolating and decimating of the reference waveform to remove Doppler effects over a broadband. The interpolation is performed by oversampling (zero padding) and low pass filtering, and the decimation is a sample rate reduction. The adaption is performed in the decimation to minimize mean square error in the canceller output.

Abstract: A retainer assembly is disclosed for retaining insulation material or the like adjacent a surface, such as an interior furnace wall. The retainer assembly comprises a longitudinally-extending member or stud and a retainer member or washer mounted thereon. The stud includes at least one throat portion. The washer comprises a body from which two prongs extend to define a channel. The prongs are folded back so that as a throat portion of the stud passes therethrough, the folded-back portions are compressed. Upon passage of the throat portions through this zone of the channel, the compressed folded-back portions of the prongs are released from compression thereby retaining the stud within a second zone of the channel.