(Received 15 September 2004; published 26 October 2004)A 201.5 MHz, 50 mA, 2.0 MeV deuteron radio frequency quadrupole accelerator is proposed as theneutron generator for the neutron experiment facility project at Peking University, China. Based onbetter understanding of beam losses, some new optimization procedures concerning both longitudinaland transverse dynamics are adopted. Accordingly, the beam transmission efficiency is improved from91.2% to 98.3% and the electrode length is shortened from 2.91 to 2.71 m. The fundamental physicalanalyses are performed to look inside the new design recipe and explain why it works.