Many thousands of simulations have been performed to verify that Liaison Navigation really works. The latest and most realistic simulation is detailed in the slide above. In this simulation, a halo orbiter at L_{2} tracks a low lunar orbiter in a polar orbit and generates crosslink range measurements. An Extended Kalman Filter is used to process the measurements in simulated realtime. Modeling errors in the orbit determination code simulate inaccurate knowledge of the radiation force models, the lunar gravity field, and the thruster models. The result is a highly accurate simulation that gives the orbit determination accuracy that can be expected in actual operation. In this case, the 1σ position error is 7 m RSS for the low lunar orbiter and 80 m RSS for the halo orbiter. It takes about a day to converge on the correct orbit for the lunar orbiter and 36 days for the halo orbiter. After the EKF converges, it can maintain this kind of accuracy indefinitely as long as there are measurements to process.
