What type of antenna systems does Iridium Satellite Systems typically utilize?

Iridium Satellite Systems primarily use omnidirectional antennas to facilitate global communication. These antennas are designed to transmit and receive signals in all directions, which is particularly important for satellite communication where the satellites are constantly moving in low Earth orbit.

The use of omnidirectional antennas allows for seamless communication with the satellites regardless of the direction the user is facing, making it ideal for mobile communication devices like handheld satellite phones. This capability ensures that users can maintain connections as they move or change orientation.

In contrast, directional antennas have a concentrated beam pattern and are more suitable for fixed points, such as ground stations relaying communication to a satellite. Large parabolic antennas, which typically provide high gain and focus on particular targets, are not practical for the consumer-oriented applications of Iridium. Hybrid antenna systems combine features of different types of antennas but are not the primary design choice for Iridium's needs. Thus, the reliance on omnidirectional antennas enables critical aspects of coverage and usability in satellite communication.