The Array 300 is an intermediate-sized spectrum monitoring and direction-finding system for vehicle-mounted deployment or fixed installations. The Array 300 uses a unique multi-layer approach that is more sophisticated and versatile than traditional direction finding. High-performance spiral directional antenna modules are optimized for different frequency bands and arranged in multiple orientations. The Array is sensitive to the majority of incoming signal polarizations including all linear polarizations, allowing reliable detection of signals including those invisible to most DF systems. It is available in three different receiver configurations either based on RFeye Node 100-8 with 100 MHz IBW and 8 GHz upper frequency, the Node 100-18 with 100 MHz IBW and 18 GHz upper frequency or the Node 100-40 with 100 MHz IBW and 40 GHz upper frequency.