V-band refers to the portion of the radio spectrum between 40 and 75 GHz, offering significantly more bandwidth than the Ka-band and Ku-band frequencies traditionally used by satellite communications. SpaceX has filed for V-band spectrum for its next-generation Starlink constellation, and Amazon's Project Kuiper also plans to use V-band capacity to deliver multi-gigabit broadband from orbit.
The primary challenge of V-band is rain fade, the attenuation of signals by atmospheric moisture that increases with frequency. V-band signals can be severely degraded during heavy precipitation, requiring adaptive coding, ground station diversity, and power margin to maintain reliable links. Despite these challenges, the sheer bandwidth available in V-band makes it essential for meeting the growing demand for high-throughput satellite services.