Abstract
To improve the volume search efficiency of a bistatic radar with the transmitting antenna and the receiving antenna positioned apart, a known beam scanning method is pulse chasing that scans the receive beam at high speed in response to the propagation of the transmitted pulses. However, in normal pulse chasing, the receive beam width cannot be narrower than some value in order to receive all of the transmitted pulses without losses. In other words, a limit is the antenna gain cannot be increased. The problem is the receive signalβtoβnoise ratio (SNR) decreases compared to when pulse chasing is not performed. In this paper, we propose multibeam pulse chasing, a beam scanning technique using multiple receive beams based on digital beam forming, as the solution. We show that even if the transmitted pulse width is relatively long, if the number of multibeams is increased, the received SNR does not exhibit a decrease. Furthermore, we study a method to decrease the number of multibeams by dropping a portion of the receive pulses when pulse compression is applied as the transmission and reception methods, and present the computational result of the relationship between the number of multibeams and the received SNR when the Taylor window is applied. Β© 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(1): 11β21, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20240