; Zhang, Xinmin] Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China
; [Zhang, Xinmin] Chinese Acad Sci, TPCSF, Beijing 100864, Peoples R China
In this paper we study the generation of primordial perturbations with a modified dispersion relation in various cosmological evolution scenarios. We stress that the formation of the power spectrum is strongly dependent on the background. By parameterizing a modified dispersion relation, we have listed all potential conditions on background evolution in order to seed scale-invariant primordial spectra. Working in a bounce model with a matterlike contracting phase, we obtain a red-tilted spectrum due to the modified dispersion relation.