Non-standard Antennas

Chapter 12Multifunction Airborne Antennas¹

 

 

 

12.1. Introduction

In the areas of detection, communications and electronic warfare, the various functions that modern airborne platforms should fulfill require the installation of numerous antennas on carriers with reduced size and limited available space.

It should also be noted that these functions operate on a frequency band globally spreading from the VHF band to the Ka band, and that the Fields of View around the carrier, the radiation patterns and the polarizations to radiate are specific to each of these functions. The physical integration of these aerials into the carrier is therefore an extremely difficult challenge, emphasized by the requirements regarding constraints on couplings between aerials (EMC) and by financial considerations.

One possible way to overcome this complexity is to gather a maximum number of radiating functions over a minimum number of aerials optimally positioned on the aircraft. This operation of gathering functions is evidently only possible if there is no simultaneity for functions shared on a single aerial, and if the radio-electric performance of any aerial is adequate to fulfil the different requirements for each radiating function it is supposed to serve.

The technique of active array antennas, which consists of distributing the RF amplifiers in proximity of the radiating elements, is particularly adapted to the design and development of multifunction antennas, as it gives way to the realization ...