Synchronisation and relative position of airborne bistatic radar

The interest in biand multistatic radar has been growing over the last years as they offer various advantages. For instance the transmitter and receiver can be easily be separated and therefore the survivability can be enhanced by deploying the transmitter further away from the scene. Even the possibility of a forward looking synthetic aperture radar can be realised. Bistatic radar can provide a cost effective solution as the transmitter and receiver can be build without the cost driven transmit/receive-modules. Beyond this, with large baselines it is likely to increase the signature from stealthy objects. Another interesting aspect of bistatic imaging radar is the reduced dynamic range of difficult imaging environments such as urban ones. However, besides the benefits of biand multistatic radar one has to solve several technical problems [3] such as the synchronisation of the stable local oscillators (STALO), the involved automatic adjustment of transmit pulse versus receive gate timing, antenna pointing and flight coordination. For a highly automatic bistatic signal processing, the baseline between the involved platforms, as well as the orientation towards each other must be known precisely besides. This paper discusses a method which allows determining these two fundamental parameters of an airborne bi-/multistatic SAR system.