The Hα line shape has been fitted with Gaussian function. Hα intensities emitted by the hydrogen atoms,which are reflected by the limiter,and produced from hydrogen molecular dissociation and charge-exchange,were obtained. We have also obtained their incident velocity and ion temperature from Doppler broadening and Doppler shift. This paper discussed the hydrogen atom transport with a simplified model gave the profile of hydrogen atom density and emission coefficient,and analyzed the influence of incident velocity on particle confinement time. Hydrogen atom energy spectra have been also derived from the Hα line shape,It shows that the main molecular processes at the edge of the plasma are hydrogen molecular dissociative excitation and ionic dissociation.