The flat and curved effect of the Earth is considered in microwave communication when planning and designing long-distance communication links, particularly those that span over significant distances, such as satellite communications and long-haul terrestrial microwave links. This consideration is essential to ensure the reliability and accuracy of the communication system.
Line of Sight (LOS) Clearance: In microwave communication, there needs to be a clear line of sight between the transmitting and receiving antennas. As the Earth is curved, the line of sight becomes obstructed by the Earth's surface as the distance between the two points increases. This curvature effect becomes more pronounced over long distances. Engineers and planners must take the Earth's curvature into account when determining the height of the transmitting and receiving antennas to achieve proper line of sight clearance.
Fresnel Zone Clearance: The Fresnel zone is an elliptical-shaped area around the direct line of sight between the antennas. It plays a crucial role in microwave link design because any obstruction within this zone can cause signal degradation. Over long distances, the Earth's curvature affects the shape and size of the Fresnel zone, making it necessary to consider both the Earth's curvature and terrain profile to maintain an obstacle-free Fresnel zone for optimal signal transmission.
Path Loss and Attenuation: The Earth's curvature can also impact the path loss and signal attenuation over long-distance microwave links. As the signal travels through the Earth's atmosphere, the curvature can affect atmospheric conditions, which, in turn, can lead to signal fading and attenuation. Antenna height and positioning are considered to optimize the signal strength and reduce the impact of these effects.
Satellite Communication: When planning for satellite communication links, the curvature of the Earth is taken into account to determine the satellite's orbital position and coverage area. Ground stations must be strategically located to maintain a clear line of sight with the satellite, considering the curvature of the Earth.
Terrestrial Microwave Links: In terrestrial microwave communication links, especially over long distances, the Earth's curvature affects the overall link budget, which includes factors like antenna heights, path loss, and signal propagation. Accurate consideration of the curvature is vital for proper alignment and successful communication.
In summary, the flat and curved effect of the Earth is considered in microwave communication for ensuring clear line of sight, unobstructed Fresnel zones, optimal signal strength, and efficient communication over long distances, both in satellite and terrestrial microwave links.