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  2. Radial velocity - Wikipedia

    en.wikipedia.org/wiki/Radial_Velocity

    A plane flying past a radar station: the plane's velocity vector (red) is the sum of the radial velocity (green) and the tangential velocity (blue). The radial velocity or line-of-sight velocity of a target with respect to an observer is the rate of change of the vector displacement between the two points.

  3. Proportional navigation - Wikipedia

    en.wikipedia.org/wiki/Proportional_navigation

    Where is the acceleration perpendicular to the missile's instantaneous velocity vector, is the proportionality constant generally having an integer value 3-5 (dimensionless), ˙ is the line of sight rate, and V is the closing velocity. Since the line of sight is not in general co-linear with the missile velocity vector, the applied acceleration ...

  4. Line-of-sight propagation - Wikipedia

    en.wikipedia.org/wiki/Line-of-sight_propagation

    Line-of-sight propagation is a characteristic of electromagnetic radiation or acoustic wave propagation which means waves can only travel in a direct visual path from the source to the receiver without obstacles. [1] Electromagnetic transmission includes light emissions traveling in a straight line. The rays or waves may be diffracted ...

  5. External ballistics - Wikipedia

    en.wikipedia.org/wiki/External_ballistics

    The projectile path crosses the horizontal sighting plane two times. The point closest to the gun occurs while the bullet is climbing through the line of sight and is called the near zero. The second point occurs as the projectile is descending through the line of sight. It is called the far zero and defines the current sight in distance for ...

  6. Radio propagation - Wikipedia

    en.wikipedia.org/wiki/Radio_propagation

    Radio propagation is the behavior of radio waves as they travel, or are propagated, from one point to another in vacuum, or into various parts of the atmosphere. [1]: 26‑1 As a form of electromagnetic radiation, like light waves, radio waves are affected by the phenomena of reflection, refraction, diffraction, absorption, polarization, and scattering. [2]

  7. Line of sight - Wikipedia

    en.wikipedia.org/wiki/Line_of_sight

    The line of sight, also known as visual axis or sightline (also sight line), is an imaginary line between a viewer/ observer / spectator 's eye (s) and a subject of interest, or their relative direction. [1] The subject may be any definable object taken note of or to be taken note of by the observer, at any distance more than least distance of ...

  8. Jefimenko's equations - Wikipedia

    en.wikipedia.org/wiki/Jefimenko's_equations

    The last term, proportional to the second derivative of the unit direction vector ′, is sensitive to charge motion perpendicular to the line of sight. It can be shown that the electric field generated by this term is proportional to a t / r ′ {\displaystyle a_{t}/r'} , where a t {\displaystyle a_{t}} is the transverse acceleration in the ...

  9. Two-ray ground-reflection model - Wikipedia

    en.wikipedia.org/wiki/Two-ray_ground-reflection...

    Two-ray ground-reflection model. The two-rays ground-reflection model is a multipath radio propagation model which predicts the path losses between a transmitting antenna and a receiving antenna when they are in line of sight (LOS). Generally, the two antenna each have different height. The received signal having two components, the LOS ...