Antenna Pointing Loss
Signal degradation resulting from imperfect alignment between a ground station antenna's beam axis and the target satellite. Expressed in dB and included as a negative term in link budget calculations.
Full Definition
Antenna pointing loss (also called mispointing loss) occurs when a ground station antenna is not precisely aligned to the satellite's position, causing the system to operate off the peak of the antenna's radiation pattern. Even small angular errors can introduce significant loss in high-gain antennas with narrow beamwidths. Pointing loss is modelled as a function of the angular error and the antenna's beamwidth pattern, and a typical margin of 0.5–1.0 dB is allocated in link budgets for this effect. Editors should render this as three open words (no hyphens) and ensure the associated angular error specification (in degrees or millidegrees) is always stated alongside the dB value in technical documents.
Usage
Usage note: Three open words, no hyphens. Always accompany with a dB value and the angular error that produces it. Do not conflate with polarisation loss, which has a separate cause and calculation.
In Context
- "A 0.1° pointing error on the 9 m antenna resulted in an antenna pointing loss of 0.8 dB at Ku-band." — Link Budget Spreadsheet
- "The link budget allocated 0.5 dB for antenna pointing loss under worst-case wind-load conditions." — System Design Document