ABSTRACT
Four fundamental approaches based on spatial discrimination are commonly adopted in antijam Global Positioning Systems (GPS). e application of these approaches requires the GPS receiver to be equipped with an antenna array. e choice between
14.2 Background ............................................................ 413 14.3 GPS Receiver Model with Dual-Polarized
Antenna Array ...................................................... 415 14.4 Single versus Multiple Antijam
Beamformers ......................................................... 418 14.5 Combined Nulling and DOA Estimation .........423 14.6 Constrained Adaptive Algorithm ......................433 14.7 An Alternative Cascade Processing
Approach ................................................................436 14.8 Summary ................................................................439 Acknowledgment .............................................................440 References .........................................................................440
which approach to undertake depends on various parameters, including the number of available satellites in the eld of view (FOV), the nature of the jamming environment, the antenna polarization characteristics, and the ability to utilize the satellite direction information. e four approaches, placed in broad categories, are:
