far-field
Beyond the near
Far-field describes the region at a significant distance from a source of radiation, sound, or electromagnetic waves, where the wave patterns have stabilized into a predictable form.
In acoustics and antenna design, the far-field is where measurements are typically taken because the waves behave uniformly and can be characterized by simple mathematical models.
This contrasts with the near-field, where wave behavior is more complex and chaotic.
The antenna's radiation pattern was measured in the far-field to ensure accuracy.
Unwelcome involvement in affairs
- apertureAdjustable optical inlet
- slitNarrow elongated opening
- gratingCrossed bars or harsh
- coherenceLogical internal consistency
wavefront · laser · holography · imaging · telescope · resolution · collimation
Unobstructed path for vision
- attenuationGradual intensity reduction
- scatteringDistribution in many directions
- diffractionWaves spreading past obstacles
- troposphericOf the lowest air layer
skywave · satellite · geostationary · horizon · telecommunications · transmitter · receiver · multipath
Antenna radiation spread
- gainPositive return received
- directivityFocused radiation capability
- electromagneticInvolving electric and magnetic fields
- transmitterSignal-emitting device
receiver · broadcast · wireless · RFID · satellite · radar · signal · microwave
Indoor film production space
- reverberationProlonged reflected sound
- echoReflected sound wave
- amphitheaterOpen-air tiered venue
- auditoriumRoom for spectators
stadium · loudspeaker · ambience · recording · soundscape · decibel
interference
Unwelcome involvement in affairs
coherence · wavefront · laser · holography · imaging · telescope · resolution · collimation
line-of-sight
Unobstructed path for vision
- attenuationGradual intensity reduction
- scatteringDistribution in many directions
- diffractionWaves spreading past obstacles
tropospheric · skywave · satellite · geostationary · horizon · telecommunications · transmitter · receiver · multipath · fading
beamwidth
Antenna radiation spread
- gainPositive return received
- directivityFocused radiation capability
- electromagneticInvolving electric and magnetic fields
transmitter · receiver · broadcast · wireless · RFID · satellite · radar · signal · microwave · radio-frequency
soundstage
Indoor film production space
- reverberationProlonged reflected sound
- echoReflected sound wave
- amphitheaterOpen-air tiered venue
auditorium · stadium · loudspeaker · ambience · recording · soundscape · decibel