A bootstrapping tandem navigation receiver system includes two independent
navigation receivers. A first uses coherent detection and makes
carrier-phase pseudorange measurements. A second uses non-coherent
detection and a longer predetection interval and thus can acquire
satellites in very weak signal environments. The second navigation
receiver delivers a bootstrapping message to the first receiver that
allows it to directly acquire the satellites without searching for them.
The first navigation receiver then drives to find carrier phase lock and
produces its more accurate measurements.