Lbanden

L-band is a portion of the microwave radio spectrum spanning roughly 1 to 2 GHz. In practice, many references consider 1.0–2.0 GHz, though exact allocations vary by region. The band lies above VHF/UHF and below higher-frequency bands, offering a balance of moderate bandwidth and favorable propagation characteristics, including relatively low atmospheric attenuation compared with higher frequencies and compact antenna sizes.

Applications of L-band are broad. It is widely used for satellite communications, including mobile satellite services and certain two-way data links, as well as for navigation systems. Global navigation satellite systems (GNSS) such as GPS, GLONASS, Galileo, and BeiDou transmit civil and military signals in L-band (for example GPS L1, L2, and L5). L-band links are valued for their robustness to weather and reasonable range, making them suitable for handheld devices and vehicle receivers, as well as ground-to-satellite and satellite-to-ground communications.

Earth observation uses also include synthetic aperture radar (SAR) systems operating in L-band, such as ALOS PALSAR. L-band SAR can provide useful information on vegetation, soil moisture, and cryospheric properties, with deeper penetration through foliage compared with higher-frequency SAR systems, albeit at different resolution characteristics.

Propagation and performance characteristics of L-band lend themselves to reliable outdoor and mobility applications, though spectrum availability is more limited than in some higher bands, which can constrain potential data rates. Regulatory allocations are governed by the ITU, with national regulators implementing additional subdivisions for fixed, mobile, radiolocation, and space research services.