Locating Simultaneous VHF Distress Calls Using a Single LEO Satellite – An Idea for Augmenting Rescue 21 in Alaska

Rescue 21 (R21) is a land-based, very high frequency (VHF) positioning and communications system used by the US Coast Guard to locate mariners in distress. In the lower 49, R21 has been celebrated as a resounding success as an invaluable aid for Search and Rescue (SAR); and system availability is generally acceptable. Unfortunately, R21 has not been as available in the far North, either directly or indirectly due to the harsh Alaskan climate. For this reason, we are looking at space-based solutions as promising ways to augment existing Coast Guard R21 distress localization and communications capabilities.