Dependency of Resolvable Gravitational Spatial Resolution on Space-Borne Observation Techniques

摘要: The so-called Colombo-Nyquist (Colombo, global mapping of gravity with two satellites, 1984) rule in satellite geodesy has been revisited. This predicts that for a gravimetric flying (near-)polar circular repeat orbit, the maximum resolvable geopotential spherical harmonic degree (lmax) is equal to half number orbital revolutions (nr) completes one period. tested different observation types, including geoid values at sea level along ground track, orbit perturbations (radial,along-track, cross-track), low-low satellite-to-satellite tracking, and gradiometry observations (all three diagonal components). Results show Colombo–Nyquist must be reformulated. Simulations indicate fact knr + 1, where k can 2, or even 3 depending on combination types. However, original correct some extent, considering quality recovered field models homogeneous as function geographical longitude long l max < nr/2.