Cell site in the context of "Satellite phone"

Mobile telephony is the provision of wireless telephone services to mobile phones, distinguishing it from fixed-location telephony provided via landline phones. Traditionally, telephony specifically refers to voice communication, though the distinction has become less clear with the integration of additional features such as text messaging and data services.

Modern mobile phones connect to a terrestrial cellular network of base stations (commonly referred to as cell sites), using radio waves to facilitate communication. Satellite phones use wireless links to orbiting satellites, providing an alternative in areas lacking local terrestrial communication infrastructure, such as landline and cellular networks. Cellular networks, satellite networks, and landline systems are all linked to the public switched telephone network (PSTN), enabling calls to be made to and from nearly any telephone worldwide.

The lead–acid battery is a type of rechargeable battery. First invented in 1859 by French physicist Gaston Planté, it was the first type of rechargeable battery ever created. Compared to the more modern rechargeable batteries, lead–acid batteries have relatively low energy density and heavier weight. Despite this, they are able to supply high surge currents. These features, along with their low cost, make them useful for motor vehicles in order to provide the high current required by starter motors. Lead–acid batteries suffer from relatively short cycle lifespan (usually less than 500 deep cycles) and overall lifespan (due to the double sulfation in the discharged state), as well as long charging times.

As they are not as expensive when compared to newer technologies, lead–acid batteries are widely used even when surge current is not important and other designs could provide higher energy densities. In 1999, lead–acid battery sales accounted for 40–50% of the value from batteries sold worldwide (excluding China and Russia), equivalent to a manufacturing market value of about US$15 billion. Large-format lead–acid designs are widely used for storage in backup power supplies in telecommunications networks such as for cell sites, high-availability emergency power systems as used in hospitals, and stand-alone power systems. For these roles, modified versions of the standard cell may be used to improve storage times and reduce maintenance requirements. Gel cell and absorbed glass mat batteries are common in these roles, collectively known as valve-regulated lead–acid (VRLA) batteries.

A satellite internet constellation is a constellation of artificial satellites providing satellite internet service. In particular, the term has come to refer to a new generation of very large constellations (sometimes referred to as megaconstellations) orbiting in low Earth orbit (LEO) to provide low-latency, high bandwidth (broadband) internet service. As of 2020, 63 percent of rural households worldwide lacked internet access due to the infrastructure requirements of underground cables and network towers. Satellite internet constellations offer a low-cost solution for expanding coverage.