enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. F region - Wikipedia

    en.wikipedia.org/wiki/F_region

    The F 2 layer exists from about 220 to 800 km (140 to 500 miles) above the surface of the Earth. The F 2 layer is the principal reflecting layer for HF radio communications during both day and night. The horizon-limited distance for one-hop F 2 propagation is usually around 4,000 km (2500 miles). The F 2 layer has about 10 6 e/cm 3. However ...

  3. F2 propagation - Wikipedia

    en.wikipedia.org/wiki/F2_propagation

    F2 propagation (F2-skip) is the reflection of VHF signals off the F2 layer of the ionosphere.The phenomenon is rare compared to other forms of propagation (such as sporadic E propagation, or E-skip) but can reflect signals thousands of miles beyond their intended broadcast area, substantially farther than E-skip.

  4. Kennelly–Heaviside layer - Wikipedia

    en.wikipedia.org/wiki/Kennelly–Heaviside_layer

    Layers of the ionosphere.The Kennelly–Heaviside layer is the E region. The Heaviside layer, [1] [2] sometimes called the Kennelly–Heaviside layer, [3] [4] named after Arthur E. Kennelly and Oliver Heaviside, is a layer of ionised gas occurring roughly between 90km and 150 km (56 and 93 mi) above the ground — one of several layers in the Earth's ionosphere.

  5. Ionosphere - Wikipedia

    en.wikipedia.org/wiki/Ionosphere

    Relationship of the atmosphere and ionosphere. The ionosphere (/ aɪ ˈ ɒ n ə ˌ s f ɪər /) [1] [2] is the ionized part of the upper atmosphere of Earth, from about 48 km (30 mi) to 965 km (600 mi) above sea level, [3] a region that includes the thermosphere and parts of the mesosphere and exosphere. The ionosphere is ionized by solar ...

  6. Critical frequency - Wikipedia

    en.wikipedia.org/wiki/Critical_frequency

    The other layers(D) interact in other ways - absorption of frequency and during the day, the D Layers forms, and the F layer splits into F1 and F2 layers. Because of changing the Ionosphere during day and night, during daytime higher frequency bands under critical Frequency work best, but during nighttime the lower frequency bands work best.

  7. Ionospheric storm - Wikipedia

    en.wikipedia.org/wiki/Ionospheric_storm

    The F-region is the highest region of the ionosphere. Consisting of the F1 and F2 layers, its distance above the Earth's surface is approximately 200–500 km. [7] The duration of these storms are around a day and reoccur every approximately 27.3 days. [6] Most ionospheric abnormalities occur in the F2 and E layers of the ionosphere.

  8. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    The various layers of Earth's ionosphere, important to HF radio propagation, begin below 100 km and extend beyond 500 km. By comparison, the International Space Station and Space Shuttle typically orbit at 350–400 km, within the F-layer of the ionosphere where they encounter enough atmospheric drag to require reboosts every few months ...

  9. High-frequency Active Auroral Research Program - Wikipedia

    en.wikipedia.org/wiki/High-frequency_Active...

    Consequently, the ionosphere consists of a rapid increase in density of free electrons, beginning at ~70 km, reaching a peak at ~300 km, and then falling off again as the atmosphere disappears entirely by ~1,000 km. Various aspects of HAARP can study all of the main layers of the ionosphere.