TABLE OF CONTENTS For the implementation of a particular radar procedure the first step is to control the transmitting beam. This can be made inertialess with electronically steered radar, using digitally controllable phase shifters and thus made completely arbitrary with respect to time and direction. As a physical fundamental condition, the delay time of the target echoes is naturally given by the speed of light and must be considered for the design of the individual radar procedures.
The receiving beam has to collect the echo signals from the same direction as that illuminated by the transmit beam. The received echo signals must then be processed. With the concept of active array antennas many degrees of freedom are available for the organisation of new radar procedures. These are generally not achievable with conventional radars using mechanical rotating reflector antennas.
A sequence of task orders is generated by the radar system's control computer according to the requirements for the radar. The function and efficiency of an individual radar procedure fulfilling the ordered task is determined to a large extent by the method of signal processing. In principle, the following basic radar tasks or functions are to be achieved within a multifunction radar (MFR). They may be mixed or combined in a time multiplex operation according to the actual priority.
Search in different range and angular areas:
remote areas without ground clutter, possibly with weather clutter
medium range with and without ground or weather clutter
short range with...
