 And, some NMT-450 analog networks have been replaced with digital networks using the same frequency.In Russia and some other countries, local carriers received licenses for 450 MHz frequency to provide CDMA mobile coverage area.Many GSM phones support three bands (900/1,800/1,900 MHz or 850/1,800/1,900 MHz) or four bands (850/900/1,800/1,900 MHz), and are usually referred to as tri-band and quad-band phones, or world phones; with such a phone one can travel internationally and use the same handset.