9.1 Introduction

In the previous chapter, the implications on the design of radar components required to support target recognition functions, were discussed. In this chapter the design issues for supporting high-range resolution modes, using two important classes of antenna, the traditional parabolic dish and the more modern phased array radars, are presented. The topics raised are representative of most types of antenna employed in target recognition. There are no critical issues for JEM associated with the antenna, as it is a narrow bandwidth mode.

In Section 9.2, parabolic dish antennas are discussed followed by phased arrays in Section 9.3. More details on antenna design can be obtained from ^[1].

9.2 Parabolic dish antennas

The parabolic dish is well suited to high-range resolution applications. Parabolic dishes have been one of the most popular designs for radar antennas over many years. The design is inherently broadband, so it can accommodate the application of wideband signals, for high-range resolution modes, without any design modifications. Radars designed for conventional radar modes usually have some frequency agility ^[2], in order to overcome deliberate jamming or interference within the band. The part of the frequency band that is in the clear is selected and used for transmitting the signal. The design of the antenna enables the electromagnetic wave to propagate in the same direction, without the need to perform any tuning or adjustments to the antenna when the...