In the past few years we have written and edited several books in the
area of acousticandspeechsignalprocessing.
Thereasonbehindthisendeavoristhat there were almost no books available
in the literature when we ?rst started while there was (and still is) a
real need to publish manuscripts summarizing the most useful ideas,
concepts, results, and state-of-the-art algorithms in this important
area of research. According to all the feedback we have received so far,
we can say that we were right in doing this. Recently, several other
researchers have followed us in this journey and have published
interesting books with their own visions and perspectives. The idea of
writing a book on Microphone Array Signal Processing comes from
discussions we have had with many colleagues and friends. As a c-
sequence of these discussions, we came up with the conclusion that,
again, there is an urgent need for a monograph that carefully explains
the theory and implementation of microphone arrays. While there are many
manuscripts on antenna arrays from a narrowband perspective (narrowband
signals and narrowband processing), the literature is quite scarce when
it comes to s- sor arrays explained from a truly broadband perspective.
Many algorithms for speech applications were simply borrowed from
narrowband antenna - rays. However, a direct application of narrowband
ideas to broadband speech processing may not be necessarily appropriate
and can lead to many m- understandings.