PROCEDURE FOR AUTONOMOUS DETERMINATION OF PROTECTION LEVELS FOR GNSS POSITIONING BASED ON NAVIGATION RESIDUES AND ON AN ISOTROPIC TRUST RELATIONSHIP.

摘要

Procedure for calculating a level of horizontal protection HPL and / or a level of vertical protection VPL, which limit up to a given level of confidence 1 - α the horizontal and vertical components, respectively, of the error of estimation of the position δ of a solution GNSS navigation based on least squares with an estimated number m of parameters, a navigation solution based on n observations and an observation matrix H of n × m, and whose navigation solution also provides a residue vector r; in which the level of horizontal protection HPL and the level of vertical protection VPL are calculated according to the following expressions: ** Formula ** in which: r is the Euclidean norm of the residual vector of the least squares estimation r; ** Formula ** - EE, NN, EN, NE, EU, EU, UU, VU, UV are the spatial components of) 1 (HT 20 DoP matrix (H tH) -1 of the least squares estimate expressed in the horizontal local coordinate system of the estimated position, where the subscripts E, N and U represent the east, north and vertical components, respectively, and their combinations correspond to their correlations and cross correlations: ** Formula ** and in which - k is an isotropic confidence relationship calculated by numerically solving the following expression Ec. 3 that links k with n, m and α: in which: ** Formula ** - Γ is Euler's gamma function ''; and, Κm - indicates a standard real m-dimensional vector space.