Narrowband EMDAR

Narrowband EMDAR uses the same passive EM detection system as broadband EMDAR but is far more directional, focussing on a very limited area of space.

The narrow focus limits the amount of detection data that needs to be processed, which means a narrowband array can calculate movement and adjust its focus accordingly, allowing it to track a moving EM source such as a TSMO.

In addition to EM detection the narrowband system utilises computational analysis which can extrapolate not just position but also the TSMO's speed. An extrapolation of the TSMO's EM emissions at source is also available, allowing assessment and comparison of a TSMO's EM 'signature'.

Achieving a Track

The successful detection of a TSMO by a narrowband array is referred to as a ‘track’.

Before a narrowband array can begin tracking a TSMO, it’s narrow area of focus means that it must be directed to the area of space within +/-100GU’s of the TSMO’s location. The contact management process allows operators to continually refine their estimate of a TSMO’s location using the broadband EMDAR system until a narrowband array can achieve a track.

Maintaining a Track

With their combination of directional EM detection and enhanced analysis, narrowband arrays can track EM sources which might not otherwise attract attention on a waterfall display.

Narrowband EMDAR is still subject to AO masking effects. For example, if an AO such as a planet comes between the tracking ship and TSMO, the track will be lost.

Equipment Limitations

Narrowband arrays are positioned around the vessel in redundant, overlapping sets. The directional nature of narrowband requires line-of-sight (LOS) to the target. An array will automatically hand off tracking to another when a target moves out of LOS.

While there are a significant number of physical narrowband arrays installed, the need to keep arrays spare at each location for tracking handoff and the significant computational resources required by the system means that only six virtual arrays are presented to operators for use. This limits the maximum number of tracks that can be maintained, but is thought to be adequate for most tactical scenarios.