GSM1800, also known as Digital Communications System 1800 (DCS1800), operates in the 1800 MHz band. This frequency band spans from 1710 – 1785 MHz for uplink and 1805 – 1880 MHz for downlink. Mobile devices transmit in the lower band, while base stations operate in the upper band. GSM1800 is a widely used standard for mobile communication services, offering efficient wireless connectivity in this frequency range.