to increase speed for HFSS 10

hi..]

i have problem in designing in hfss....im using hfss v10.im using window vista.my problem is my simulation time take very long time ( around 6 hour to 12 hours).im designing microstrip antenna.im using airbox size 350mm(5 *height)...i dont know maybe my setting is wrong...i hope anybody can help me

your radiation boundary airbox should be a little bit bigger then the wavelength of the frequency you are solving for assuming your object is in the center of the box. You can set metal objects as vacuum and assign Perfect Electric Conductor Boundary. You can also replace some 3D objects like the microstrip trace on the board with a 2D sheet and assign it PEC. To save time you can also limit the # of passes you solve if you can tolerate the change in accuracy.