How Mobile Communication Works
Your mobile phone transmits and receives low-power radio signals between antennas attached to transmitters and receivers known as cell towers or cellphone masts – these masts connect directly with public network fixed phones and mobile switching centres.
Your cellphone converts your voice to radio signals that travel through the air to reach its closest cellphone mast, where they are transmitted over a control channel to a base station for further transmission.
Cellular technology relies on radio waves to connect phones to a mobile phone network. Your microphone converts sound into electrical signals that are then converted to numbers by the microchip inside your phone before being sent through its transmitter antenna and beamed out over radio waves towards cell towers (cellphone masts) which then pass them along until reaching an area called cells, each with their own base station in the network.
Cellular systems employ various modulation and access schemes, including frequency-division multiplexing (FDMA), time-division multiplexing (TDMA), and code-division multiple access (CDMA), to allow phones to communicate over long distances without dropping calls. Each phone broadcasts its unique radio signal when near base stations.
An antenna on a phone reflects and captures radio waves, making them available for processing by devices such as smartphones. Though antennas may often be taken for granted or overlooked when designing phones, they play an essential part of design.
An antenna works by combining elements with different lengths to form an impedance matching system at a particular frequency. For instance, a quarter wave dipole consists of one long driven element and three shorter elements called directors that work in concert to match impedance at that frequency.
When a mobile phone wants to call another on its network, it transmits its digitized identification code to its closest cell tower and then to a base station that oversees what happens across its cells (groups of phones). Finally, this base station routes the call directly between handsets.
Your voice is picked up by the microphone inside your phone, processed into digital signals that consist of zeros and ones, then beamed out via its transmitter antenna as electromagnetic waves.
These waves travel until they reach a nearby cell tower or cellphone mast, which then transmits it to a base station that coordinates activities within each of its network cells (called cells).
As you move between cell areas while on a call, your phone will search for a channel so as to not drop the connection. To achieve this goal, it establishes radio links with multiple nearby cells simultaneously to achieve soft handover. This process utilizes multiple radio channels along with techniques such as frequency division, time division and code division which enable this.
Your mobile phone’s microphone converts sound waves into electrical signals that are then converted and transmitted via radio transceiver to the nearest cell tower or cellphone mast using radio transceivers, where transmitter antennae relay these signals on to a base station that coordinates between different cells on its network and routes calls accordingly.
Cell phones and their base stations utilize various frequencies, each assigned to a cell. Cell tower sites and mobile devices then adjust these frequencies so as to not interfere with other subscribers.
Receivers contain mixers which alter incoming radio frequency signals from antennae into lower intermediate frequencies by means of mixing, creating heterodyne beat frequencies which produce audible audio at their outputs.
Cellular towers (commonly referred to as masts) are tall antennas designed to broadcast cellular phone signals throughout an area. As the foundation for cellular networks, these towers ensure near instantaneous connections between mobile devices across its network.
When talking on a cellphone, its microphone converts soundwaves into electrical signals, which are converted by a microchip into numbers before being sent through its transmitter antenna as radio frequency (RF) waves to reach a cell tower and be routed through backhaul connections back to its mobile switching center.
The Mobile Switching Center then communicates with mobile phones over a control channel to inform them which frequencies to use and monitor their location as they move between cells. By switching masts as necessary, mobile phones are able to seamlessly move from cell to cell without interference from MSCs.