▁on ▁a ▁secondary ▁basis . ▁ ▁It ▁ranges ▁from ▁ 9 0 2 ▁to ▁ 9 2 8 ▁M Hz ▁and ▁is ▁unique ▁to ▁IT U ▁Region ▁ 2 . ▁ ▁It ▁is ▁primarily ▁used ▁for ▁very ▁local ▁communic ations ▁as ▁opposed ▁to ▁bands ▁lower ▁in ▁frequency . ▁ ▁However , ▁very ▁high ▁anten nas ▁with ▁high ▁gain ▁have ▁shown ▁ 3 3 ▁cent im eters ▁can ▁provide ▁good ▁long - range ▁communic ations ▁almost ▁equal ▁to ▁systems ▁on ▁lower ▁frequencies ▁such ▁as ▁the ▁ 7 0 ▁cent imeter ▁band . ▁ ▁The ▁band ▁is ▁also ▁used ▁by ▁industrial , ▁scientific , ▁and ▁medical ▁( IS M ) ▁equipment , ▁as ▁well ▁as ▁low - power ed ▁un lic ensed ▁devices . ▁ ▁Am ateur ▁stations ▁must ▁accept ▁harm ful ▁inter ference ▁caused ▁by ▁IS M ▁users ▁but ▁may ▁receive ▁protection ▁from ▁un lic ensed ▁devices . ▁ ▁The ▁ 9 0 0   M Hz ▁frequency ▁is ▁also ▁used ▁as ▁a ▁reference ▁band ▁e . g . ▁to ▁express ▁the ▁total ▁power ▁or ▁impact ▁of ▁the ▁electric ▁field ▁" E " ▁- ▁expressed ▁in ▁V / m ▁- ▁or ▁the ▁power ▁density ▁" S " ▁- ▁expressed ▁in ▁W / m 2 ▁- ▁of ▁the ▁overall ▁cell ular ▁frequencies ▁emission ▁caused ▁by ▁all ▁frequencies ▁s . a . ▁the ▁four ▁bands ▁ 8 5 0 ▁/ ▁ 9 0 0 ▁/ ▁ 1 , 8 0 0 ▁/ ▁ 1 , 9 0 0   M Hz ▁– ▁which ▁many ▁G SM