A Directional Acoustic Receiver as a Space Filter

Abstract

The performance of a directional acoustic receiver can be treated with the same mathematics used in treating electric filters. The output of a scanning directional receiver is related to the distribution of sound sources to which it is listening in the same way that the signal out of an electric filter is related to its input signal. The “space frequency” response of a directional receiver is determined by the physical construction of the receiver. In many cases it is possible to improve this response by the use of an appropriate electrical equalizing system on the output of the receiver. After a review of the general concept of space filtering and its particular application to receiving systems, some of the problems encountered in designing optimum equalizing systems will be discussed.