Future　wireless　communication　systems　make　high　requirements　on　the　ultra　wide　bandwidth　as　well　as　on　the　super　high　data　rates.　In　this　paper,　we　proposed　a　powerful　0.22　THz　sinusoidal　signal　generator,　which　could　be　used　as　the　power　sources　of　carrier　frequencies　or　local　oscillators　in　heterodyne　systems.　The　physical　mechanism　of　THz　wave　generation　was　related　to　the　Cherenkov　radiation,　and　the　mathematical　model　of　the　generator　was　set　up　based　on　the　nonlinear　beam-wave　interaction.　With　2.5D　particle-in-cell　simulation,　we　investigated　the　operating　characteristics　of　the　oscillator,　and　found　that　the　output　power　about　8　MW　could　be　obtained　in　the　steady　status　when　the　operating　point　located　in　the　first　Brillion　region.