The transmitting multi-beam forming technique of wideband LFM radar is studied in this paper. To deal with the aperture effects in wideband phased array radar,a low cost and low complexity method based on time-varying weighting is proposed. An S-band 4-element protype system is designed and tested,which fractional bandwidth is over 20% and the center frequency is 2. 45 GHz. In this system,the weighting coefficients of beamforming and channel calibration are modulated to the LFM signal in the transmit radio-...