TABLE OF CONTENTS In this book we will consider antenna arrays which consist of many individual antenna elements, and therefore a large number of signals, one for each element, has to be processed at the same time. The signals can be assigned to locations on the antenna, forming discrete sampling of the spatial wave field for transmitting or receiving. Signals transmitted or received with a radar system also have to be represented as a function of time. Signal samples are formed in the special and temporal dimension for digital signal processing with signal processors or computers and for recording for later analysis.
These samples z are measured generally with the complex components x and y, i.e. they are to be written as complex values. The description of z by the amplitude a and the phase ? is equivalent. An individual signal is thus given by:
The components x and y are usually called I and Q components for inphase and quadrature phase. The sequences of samples can be produced in such a way as to be equivalent to the original time-continuous signal. More precise information on sampling will follow in chapter 6.
We will write matrices with bold-face letters. Two-dimensional matrices will be written with bold-face capital letters. One-dimensional matrices (rows or columns) are also named vectors.
A temporal sequence of signals must be numbered for identification. We write for the sequence z n, with n =...
