ISIS

The ISIS Array (Intercepted Signals for Ionospheric Science) is an
instrumentation project currently funded by the DoD DURIP program via
AFOSR and the National Science Foundation. This project is
constructing a coherent software radio network capable of operating as
a flexible multi-role distributed radio science instrument. In
particular operational modes involving active and passive multistatic
radar imaging, satellite beacon observation of TEC and scintillation,
and radio intercept and time difference of arrival applications will
be supported over a wide range of operating frequencies (0.5 to 2000
MHz). The system will be constructed of a series of MIDAS-Mobile Nodes
which can coherently capture wide bandwidths of RF signals from a
variety of antennas. The array will be capable of applying high
performance supercomputing to the real time and batch processing
requirements of a variety of experiments. Different operational modes
may require the array to be configured with different antennas,
however the underlying software radar technology will allow a unified
data, signal processing, and instrument control system. The system
will also be used to evaluate a wide variety of configurations and
techniques for applications involving scientific and defense
applications of intercepted signals.
Currently seven ISIS array nodes have been constructed for the initial
deployment with an additional equivalent capability located at the MIT
Haystack Observatory. Long term plans include additional highly integrated
receivers, a significantly expanded array, and experiments with the
capabilities provided by much higher antenna apertures using antennas
located at the NSF supported NRAO Green Bank facility.