Adaptive geolocation and blind beamforming for wideband fast frequency-hop signals of unknown hop sequences and unknown arrival angles using an electromagnetic vector sensor
Kainam Thomas Wong · 2002
This paper introduces a sensor-array geolocation and blind interference rejection algorithm for multiple noncooperative wideband fast frequency-hop (FFH) spread spectrum signals of unknown hop sequences and unknown arrival angles. This algorithm avoids the need to adjust beamforming weights to accommodate frequency variations in the frequency-hopping signals. This method also exploits the sources' polarizational diversity in addition to their diversity in spatial angles and temporal characteristics. This novel approach deploys one electromagnetic vector sensor, which is composed of six spatially co-located non-isotropic polarization-sensitive antennas measuring all six electromagnetic-field components of the incident wave-field. The spatial co-location of all component antennas comprising such a vector-sensor frees the beamforming weights of any dependence on the signals' hopping frequencies. This algorithm is also applicable to blind co-channel interference rejection in frequency-hop code-division multiple access (CDMA) wireless communications.