Navigation Aids Performance Evaluation for Precision Approaches

Table 1

Sensor global accuracy error budget expressed in terms of average 𝜀 and variance 𝜎².

ILS error
Average [m]	Variance* [m^2]
7.70	93.17
GPS error
Average [m]	Variance [m^2]
6.00	8.98
SBAS error
Average [m]	Variance [m^2]
3.00	1.75
GBAS error
Average [m]	Variance [m^2]
1.03	0.46

^∗The high value of the variance can be noted. In the considered case, the calculated errors show a horizontal component (𝜀_ℎ=5.83, 𝜎²_ℎ=25.80), better than the vertical one (𝜀_𝑣=5.03, 𝜎²_𝑣=89.53).