Target classification by echo locating animals

In this paper, the principal mechanisms by which bats are assumed to classify targets are reviewed. Particular attention is paid to the ways in which bats might extract information from echoes. Classification mechanisms differ fundamentally according to signal design. It is shown how bats design their emitted waveforms according to whether they need to classify on the basis of micro-Doppler or range profile information. Throughout, analogies are made with radar (and sonar) systems, drawing attention to some ways in which engineers might learn from the classification mechanisms proposed for echo locating animals.