When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Pencil (optics) - Wikipedia

    en.wikipedia.org/wiki/Pencil_(optics)

    A pencil-beam radar A moving or sweeping pencil-beam radar. In optics, a pencil or pencil of rays, also known as a pencil beam or narrow beam, is a geometric construct (pencil of half-lines) used to describe a beam or portion of a beam of electromagnetic radiation or charged particles, typically in the form of a cone or cylinder.

  3. Radar signal characteristics - Wikipedia

    en.wikipedia.org/wiki/Radar_signal_characteristics

    Consider the following example : if the radar antenna is located at around 15 m above sea level, then the distance to the horizon is pretty close, (perhaps 15 km). Ground targets further than this range cannot be detected, so the PRF can be quite high; a radar with a PRF of 7.5 kHz will return ambiguous echoes from targets at about 20 km, or ...

  4. Beamforming - Wikipedia

    en.wikipedia.org/wiki/Beamforming

    Beamforming or spatial filtering is a signal processing technique used in sensor arrays for directional signal transmission or reception. [1] This is achieved by combining elements in an antenna array in such a way that signals at particular angles experience constructive interference while others experience destructive interference.

  5. Radar cross section - Wikipedia

    en.wikipedia.org/wiki/Radar_cross_section

    Typical RCS diagram (A-26 Invader) Radar cross-section (RCS), denoted σ, also called radar signature, is a measure of how detectable an object is by radar. A larger RCS indicates that an object is more easily detected. [1] An object reflects a limited amount of radar energy back to the source. The factors that influence this include: [1]

  6. Monopulse radar - Wikipedia

    en.wikipedia.org/wiki/Monopulse_radar

    Monopulse radar is a radar system that uses additional encoding of the radio signal to provide accurate directional information. The name refers to its ability to extract range and direction from a single signal pulse. Monopulse radar avoids problems seen in conical scanning radar systems, which can be confused by rapid changes in signal strength.

  7. 3D radar - Wikipedia

    en.wikipedia.org/wiki/3D_radar

    Stacked beam radars emit and/or receive multiple beams of radio waves at two or more elevation angles. By comparing the relative strengths of the returns from each beam, the elevation of the target can be deduced. An example of a stacked beam radar is the Air Route Surveillance Radar.

  8. Radar engineering - Wikipedia

    en.wikipedia.org/wiki/Radar_engineering

    Radar engineering is the design of technical aspects pertaining to the components of a radar and their ability to detect the return energy from moving scatterers — determining an object's position or obstruction in the environment.

  9. Radar - Wikipedia

    en.wikipedia.org/wiki/Radar

    The radar mile is the time it takes for a radar pulse to travel one nautical mile, reflect off a target, and return to the radar antenna. Since a nautical mile is defined as 1,852 m, then dividing this distance by the speed of light (299,792,458 m/s), and then multiplying the result by 2 yields a result of 12.36 μs in duration.