Leonardo-Finmeccanica is undertaking a TDP (technology demonstrator program) on behalf of the UK Ministry of Defence to study a new IFF system for the Eurofighter Typhoon that incorporates active electronically-scanned antenna technology. The study follows on from development of a similar system for the Saab Gripen E, and is aimed at not only upgrading the Typhoon’s existing IFF functions, but also preparing it for installation alongside the Captor-E “e-scan” radar. In any case, Typhoon is due for an IFF upgrade to meet civilian Mode S requirements in 2017, and military Mode 5 needs in 2019.

Based on the M248 transponder and SIT 2010 crypto equipment, the “e-scan” installation is to be placed in the Typhoon’s wingroots, from where the antennas can scan more than 180 degrees. In the Gripen E installation, they are distributed around the forward fuselage.

With a mechanically-scanned radar, IFF is traditionally mounted on the antenna, but this is more difficult with repositioning “e-scan” radars, although it is possible to dedicate some portions of the antenna to IFF duties. By using separate antennas, the IFF can operate independently from the radar, albeit with the systems interacting digitally. Looking out to the side, the IFF antennas could allow the Typhoon to passively “stalk” other aircraft in some scenarios.

In the initial phase of the TDP, the transponder/crypto units are due to be flown with the existing antennas in the last quarter of this year. “E-scan” antennas and the interrogator unit are scheduled to be demonstrated next year. The TDP is to culminate in a demonstration of the operational benefits.