Abstract: The survivable ground base sensor is the basic element of a land-based distributed radar that consists of 60 or more individual subarrays, which are located in either a straight line or on the perimeter of a 200 nmi diameter circle in the north central U.S. At least 10 nmi separation is provided between individual subarrays. Each subarray is self-contained with emergency power and is operated unattended. There is no need for any interconnection between subarrays so that the survivability is improved, and there is no limit to the number of subarrays used except that imposed by cost and the desire for greater survivability. Since the spacing between subarrays is 10 nmi, a direct hit on one subarray will not damage an adjacent one so that a separate re-entry vehicles must be targeted to each subarray.