Radar i APS-systemer

FFI-project 798, “Anti-Armour Weapons beyond 2000” has performed a study on active protection systems (APS). As part of this work, this report discusses the performance of radars. First the report presents requirements for an APS-system to be effective against various threats. On the basis of simple radar theory, which is described in some detail, a comparison between requirements and potential radar performance has been carried out. We found that a reasonably cheap 5GHz radar can detect threats at a range of 3000 m, even under adverse weather conditions. The resolution is, however, poor, and the radar can not determine whether one or several objects are approaching. A more expensive radar, with frequency 30GHz or more, has to be used for tracking. All in all radar is under most conditions well suited for use in most APS-systems. Radars might, however, have problems when exposed to jamming. A stationary jammer blinded all investigated frequencies, with the exception of 60GHz. When the jammer was co-located with the threat, and hence approaching the radar, the results were even worse. For frequencies of 5, 30, 60 and 100GHz we then found, under our assumptions, a detection range of less than a meter. The simultaneous use of several different types of sensors might reduce the effect of such jamming.