mobile telephone, also called mobile phone, cell phone: young girl using cell phone and laptop computer portable device for connecting to a telecommunications network in order to transmit and receive voice, video, or other data. Mobile phones typically connect to the public switched telephone network (PSTN) through one of two categories: cellular telephone systems or global satellite-based telephony.
Cellular telephones
cell phone mobile telephone: teenage girl using cell phone and laptop computer Cellular telephones, or simply cell phones, are portable devices that may be used in motor vehicles or by pedestrians. Communicating by radio waves, they permit a significant degree of mobility within a defined serving region that may range in area from a few city blocks to hundreds of square kilometres. The first mobile and portable subscriber units for cellular systems were large and heavy. With significant advances in component technology, though, the weight and size of portable transceivers have been significantly reduced. In this section, the concept of cell phones and the development of cellular systems are discussed.