Ad
related to: tv antenna range calculator
Search results
Results from the WOW.Com Content Network
The FCC procedure to calculate HAAT is: from the proposed or actual antenna site, either 12 or 16 radials were drawn, and points at 2, 4, 6, 8, and 10 miles (16 km) radius along each radial were used. The entire radial graph could be rotated to achieve the best effect for the station.
For directional antennas, the Yagi antenna is the most widely used as a high gain or "beam" antenna. For television reception, the Yagi is used, as well as the log-periodic antenna due to its wider bandwidth. Helical and turnstile antennas are used for satellite communication since they employ circular polarization.
A short antenna pole next to a house Multiple Yagi TV aerials. Antennas are commonly placed on rooftops and sometimes in attics. Placing an antenna indoors significantly attenuates the level of the available signal. [19] [20] Directional antennas must be pointed at the transmitter they are receiving; in most cases great accuracy is not needed ...
For a given frequency, the antenna's effective area is proportional to the gain. An antenna's effective length is proportional to the square root of the antenna's gain for a particular frequency and radiation resistance. Due to reciprocity, the gain of any antenna when receiving is equal to its gain when transmitting.
The latter factor is quantified by the antenna gain, which is the ratio of the signal strength radiated by an antenna in its direction of maximum radiation to that radiated by a standard antenna. For example, a 1,000 watt transmitter feeding an antenna with a gain of 4× (equiv. 6 dBi) will have the same signal strength in the direction of its ...
The first technique developed was the far-field range, where the antenna under test (AUT) is placed in the far-field of a range antenna. Due to the size required to create a far-field range for large antennas, near-field techniques were developed, which allow the measurement of the field on a distance close to the antenna (typically 3 to 10 ...
Their impedance can be made relatively constant over a frequency range 4:1 or more, with the forward gain increasing at 6 dB per octave. Multiple rhombic antennas can be connected in an end-to-end fashion to form MUSA (Multiple Unit Steerable Antenna). MUSA arrays can receive long distance, short wave, horizontally polarized downcoming waves.
The radio horizon is the locus of points at which direct rays from an antenna are tangential to the surface of the Earth. If the Earth were a perfect sphere without an atmosphere, the radio horizon would be a circle. The radio horizon of the transmitting and receiving antennas can be added together to increase the effective communication range.
Ad
related to: tv antenna range calculator