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2. Antenna boresight - Wikipedia

   en.wikipedia.org/wiki/Antenna_boresight

   For most antennas the boresight is the axis of symmetry of the antenna. For example, for axial-fed dish antennas, the antenna boresight is the axis of symmetry of the parabolic dish, and the antenna radiation pattern (the main lobe) is symmetrical about the boresight axis. Most antennas boresight axis is fixed by their shape and cannot be changed.

3. Half-power point - Wikipedia

   en.wikipedia.org/wiki/Half-power_point

   The half-power point is the angle off boresight at which the antenna gain first falls to half power (approximately −3 dB) [a] from the peak. The angle between the −3 dB points is known as the half-power beam width (or simply beam width). [4] Beamwidth is usually but not always expressed in degrees and for the horizontal plane.

4. Parabolic antenna - Wikipedia

   en.wikipedia.org/wiki/Parabolic_antenna

   Off-axis or offset feed – The reflector is an asymmetrical segment of a paraboloid, so the focus, and the feed antenna, are located to one side of the dish. The purpose of this design is to move the feed structure out of the beam path, so it does not block the beam.

5. Direction finding - Wikipedia

   en.wikipedia.org/wiki/Direction_finding

   If the antenna main lobe patterns have a Gaussian characteristic, and the signal powers are described in logarithmic terms (e.g. decibels (dB) relative to the boresight value), then there is a linear relationship between the bearing angle φ and the power level difference, i.e. φ ∝ (P1(dB) - P2(dB)), where P1(dB) and P2(dB) are the outputs ...

6. R-73 (missile) - Wikipedia

   en.wikipedia.org/wiki/R-73_(missile)

   The R-73 is an infrared homing (heat-seeking) missile with a sensitive, cryogenic cooled seeker with a substantial "off-boresight" capability: the seeker can detect targets up to 40° off the missile's centerline. [7] It can be targeted by a helmet-mounted sight (HMS) allowing pilots to designate targets by looking at them. Minimum engagement ...

7. Radiation pattern - Wikipedia

   en.wikipedia.org/wiki/Radiation_pattern

   Here, the angles and indicate a dependence on direction from the antenna, and stands for the power the transmitter would deliver into a matched load. The gain G {\displaystyle G} may be broken down into three factors; the antenna gain (the directional redistribution of the power), the radiation efficiency (accounting for ohmic losses in the ...

8. Air traffic control radar beacon system - Wikipedia

   en.wikipedia.org/wiki/Air_traffic_control_radar...

   The omnidirectional antenna is mounted near and high, usually on top of the radome if equipped. Mode-S interrogators require the sum and difference channels to provide the monopulse capability to measure the off-boresight angle of the transponder reply. The SSR repetitively transmits interrogations as the rotating radar antenna scans the sky.

9. Boresight - Wikipedia

   en.wikipedia.org/wiki/Boresight

   Boresight may refer to: Antenna boresight, the optical axis of a directional antenna; Boresight (firearm), adjustments made to an optical sight, to align the barrel of a firearm with the sights; Boresight point, also known as gun harmonisation, the alignment of weapons in an aircraft; Project Boresight, a US radio direction finding system