I was googling about particle cannon principles and this site appeared to be interesting. Check it out and then say what you think about this version.
Also try searching the web for HELEX (High Energy Laser Experimental) and LATEX (Laser Associated with an Experimental Turret) to see german and french SDI projects, used by the americans. You may find some interesting materials about it.
PS: SDI=>Strategic Defense Initiation. An anti-ICBM system, including missile complexes and orbital laser platforms.