No, not all communication satellites have to enter Low Earth Orbit (LEO) from Geostationary Orbit (GEO). In fact, most communication satellites that are intended for LEO operate directly in that orbit and do not pass through GEO at any point.
Geostationary Orbit is a specific type of orbit located at an altitude of approximately 35,786 kilometers (22,236 miles) above the Earth's equator. Satellites in GEO orbit match the Earth's rotation, allowing them to remain fixed in a specific position relative to the Earth's surface. These satellites are commonly used for telecommunications, broadcasting, and other long-term communication services.
On the other hand, Low Earth Orbit refers to orbits that are much closer to the Earth's surface, typically ranging from a few hundred kilometers to around 2,000 kilometers (about 124 to 1,243 miles) above the Earth. LEO satellites move at a faster pace relative to the Earth's rotation and complete orbits in a much shorter time, often within a couple of hours.
Communication satellites in LEO are commonly used for various purposes, including global internet connectivity, remote sensing, Earth observation, and some types of mobile communication systems. They provide advantages such as lower latency, as the shorter distance between the satellite and the ground reduces the time it takes for signals to travel.
While there are cases where satellites transition between different orbits, such as transferring from LEO to GEO or vice versa, it is not a requirement for all communication satellites to pass through GEO when moving into LEO. Many LEO satellites are launched directly into their intended orbits, avoiding the need for an intermediate transfer through GEO.