Persistent wide-area border and frontier screening

A border service must watch thousands of kilometres of frontier through terrain no patrol can cover continuously — and needs to be cued to the exact point where something changed, not handed the whole line. Commercial tasking is too sparse and expensive to blanket a border every few days. ETD is the persistent screening layer beneath the operation: enhanced 1 m visual, all-weather 2 m SAR (day, night, through cloud), 25 m night-lights and a 1 m DEM for line-of-sight, worldwide, every 2–3 days, with a decade-deep archive that establishes verifiable baselines. It flags new crossing trails, staging areas, construction near the line and coastal activity — turning wide-area coverage into class-transition alerts that trigger UAV, aerial or high-resolution tasking only where it matters.