GNSS	Global navigation satellite system
MLE	Maximum likelihood estimation
GLRT	Generalized likelihood ratio test
PVT	Position, velocity, and time
GPS	Global Positioning System
PMU	Phasor measurement units
INS	Inertial navigation system
SSSC	Spread spectrum security code
NMA	Navigation message authentication
SQM	Signal quality monitoring
RAIM	Receiver autonomous integrity monitoring
TEXBAT	Texas Spoofing Test Battery
AWGN	Additive white Gaussian noise
ECEF	Earth-centered Earth-fixed
ROC	Receiver operating characteristic
SCER	Security code estimation and replay