Transversal Filters for Pulse Spectroscopy

Transversal filtering consists of forming an output signal from the suitably weighted sum of successively delayed samples of a given input waveform. Although such filters exhibit many attractive features, economic considerations have previously limited their hardware implementation to rather few areas, primarily the fields of communications and radar. However, recent technological developments have significantly reduced the cost of the multiple tapped-delay operations that are required in such filters, thereby greatly expanding their potential areas of application. The purpose of the present paper is two-fold, first to serve as a general introduction to the possibilities of transversal filters for the processing of isolated randomaly distributed pulses (such as occur in experimental nuclear physics), and second to introduce a new implementation of such filters in the form of capacitively tapped delay lines. This latter form of transversal filter is readily fabricated and is well suited for operation on pulses in the few nanosecond to few microsecond time range.