An Investigation of Noise and Bias Effects on Doppler-Inertial Navigation System Accuracy

摘要

An analytical investigation is performed to determine and compare the performances of four second-order and third-order Doppler-inertial navigation system configurations when subjected to sensor errors. This is done by determining the steady-state rms velocity output error due to noise and bias inputs for the gyro and Doppler radar and by determining the characteristics of the transient error in velocity due to step inputs of accelerometer, gyro, and Doppler bias. Simulation of the system error models in block diagram form is accomplished by Midas programming of a digital computer. The noise analysis simulation is based on the assumption that the random process is ergodic and representable by an exponential autocorrelation function. The results indicate that system performance is highly dependent upon the manner of utilizing the mixed Doppler-inertial velocity information in feedback loops and upon the dynamic response characteristics required of the system. Midas digital simulation was found to be a useful analytical tool for studies of this nature. (Author)