Principles of space-time array processing for ultrawide-bandimpulse radar and radio communications

摘要

The emerging ultrawide-band (UWB) impulse technology has foundnnumerous applications in the commercial as well as the military sector.nThe rapid technological advances have made it possible to implementn(cost-effective, short-range) impulse radar and impulse-radioncommunication and localization systems. Array beamforming and space-timenprocessing techniques promise further advancement in the operationalncapabilities of impulse radar and impulse-radio communications tonachieve long-range coverage, high capacity and interference-free qualitynof reception. We introduce a realistic signal model for UWB impulsenwaveforms and develop the principles of space-time array processingnbased on the signal model. A space-time resolution function (STRF), anspace-frequency distribution function (SFDF) and a monopulse-trackingnsignal are derived for impulse waveforms received by a self-steeringnarray beamforming system. The directivity peak-power pattern and energynpattern of the beamformer are also derived. Computer plots of the STRF,nSFDF and the beam patterns are obtained. The directivity beam patternsnof impulse waveforms are sidelobe-free and, therefore, there is no neednfor sidelobe suppression via amplitude weighting of the array elements.nAlso, the resolution angle for the beam patterns is derived as andecreasing function of array size and frequency bandwidth. Electronicnbeamsteering based on slope processing of monopulse waveforms isndescribed