Thomson-CSF ARCANA Info Sought

I’ve been reading through the various threads about the Mirage IV and wondered if anyone had information about the radar used – the Thomson-CSF ARCANA in the Mirage IVP? I have Googled and Googled with limited success. I know that it is derieved from the Iguane and Varan radars of the Atlantic and Guardian respectively and that the Mirage IV was originally supposed to have the Antilope but due to tech problems with its development in the mid-80’s this didn’t occur. I also know that it was a SAR radar, but that’s about all.

Does anyone know anything about its performance – range, TF or TA, limited scanning to the forward 90 or 180 degrees or was it a 360 degree scan etc and any comparisons with comparable sets? Also why was it located under the forward fuselage and not in the nose as you would expect. Surely they could have relocated the IRP somewhere else. That said, did this location affect its performance?

Anyway, any information would be appreicated.