Radar cross section is the measure of a target's ability to reflect radar signals in the direction of the radar receiver, i.e. it
is a measure of the ratio of backscatter power per steradian (unit solid angle) in the direction of the radar (from the target)
to the power density that is intercepted by the target.
In 2001 I was contacted by a consortium of research institutions and wind energy
interests with a request to provide some background information on the operational
characteristics of acoustic radars or SODARs. The consortium partners had set
up and been funded for an European EU project to evaluate SODARs as a tool in
monitoring wind flows at wind turbine sites. They felt reasonably confident in their
knowledge of SODARs and had purchased some instruments, but wanted to be able
to consult on any more complex issues which arose.
The Society makes every effort to ensure that the scientific and production quality of its books matches that
of its journals. Since 1997, all book proposals have been refereed by specialist reviewers as well as by the
Society’s Books Editorial Committee. If the referees identify weaknesses in the proposal, these must be
addressed before the proposal is accepted.
Once the book is accepted, the Society Book Editors ensure that the volume editors follow strict
guidelines on refereeing and quality control.
14.1 14.2 14.3 14.4 14.5 14.6 14.7 Introduction: Acoustic and Hybrid Echoes Telephone Line Hybrid Echo Hybrid Echo Suppression Adaptive Echo Cancellation Acoustic Echo Sub-band Acoustic Echo Cancellation Summary
cho is the repetition of a waveform due to reflection from points where the characteristics of the medium through which the wave propagates changes. Echo is usefully employed in sonar and radar for detection and exploration purposes. In telecommunication, echo can degrade the quality of service, and echo cancellation is an important part of communication systems.