A Mobile Network is a system that allows users to communicate wirelessly over large geographical areas by using a series of interconnected base stations. Each base station contains large transmitters and receivers which facilitate communication between user devices. Modern day Mobile Networks can be thought of as enormous wireless internet connections, similar in many ways to a simple WiFi modem but on a much grander scale.

Mobile Network Operators (MNO's) are companies who have built and operate their own network infrastructure. This is contrasted to Mobile Virtual Network Operators (MVNOs), which are far greater in numbers, who rebrand and sell access to another company's network.

Each MNO operates one or more frequencies called carriers which, not surprisingly, are used carry data through the air. Data are encoded onto a carrier frequency according to a common standard, such as 3G, 4G, or 5G. Each standard details the digital techniques used to encode the data and the antenna techniques used to transmit the carrier, along with detailing how multiple carriers can be operated together to provide greater speed.