Contents
What is antenna isolation?
Antenna isolation is a measure of how easily one antenna will pick up radiation from another antenna, which is quantified in terms of S12 between the two antenna elements. Typical isolation goals are set to at least +20 dB, depending on the product, and isolation can be measured with a vector network analyzer.
How do I increase antenna isolation?
The simplest solution to improve the antenna isolation is to increase the physical separation between the antennas. Although the isolation of the antennas becomes higher as the separation length is increased, the size of the antenna will subsequently be larger.
Should an FM antenna be vertical or horizontal?
FM signals were originally horizontally polarized (Hpol), but now, circular polarization (Cpol) is used almost exclusively. Sometimes, the signal separation provided by vertical versus horizontal polarization is used to prevent interference between NCE stations.
Can two antennas interfere with each other?
Placing two antennas within ~1/2 wavelength of each other will cause them to inductively couple – effectively connecting themselves to each other. This results in detuning both antennas, as well as the high power Tx RF getting routed back down the other antenna, possibly damaging the receiver.
How far apart do antennas need to be?
As a general rule, the inside antenna and the outside antennas need 20 feet vertical OR 50 feet horizontal separation. If those distances are not feasible for your application, it can be achieved by doing a combination of the two (E.g, 10 feet vertical AND 30 feet horizontal).
How far apart do VHF antennas need to be?
6 feet
NMEA recommends 6 feet of vertical and horizontal separation between the VHF and AIS antennas.
What is mutual coupling in antenna?
Mutual coupling is the electromagnetic interaction between the antenna elements in an array. Mutual coupling is inversely proportional to the spacing between the different antenna elements in an array. Mutual coupling in an array causes: Changes in the radiation pattern of the array.
Can you use a TV antenna for AM radio?
They other guys are right, a TV antenna will not work on AM. The loop antenna inside your clock radio will work better on AM than a TV antenna. If you really want to improve AM reception you could get a Select-a-tenna; it’s basically a large AM loop antenna inside a round plastic box.
Which is the best definition of antenna isolation?
Antenna isolation is a measure of power transfer from one antenna to another (Transmit Tx to Receive Rx), generally represented as a loss in dB. As a general rule, the antenna isolation should be as large as possible to minimize interference between systems and can be maximised by:
Is there isolation between antennas of IMT base stations?
In this Report the isolation between co-located antennas and antennas in close proximity of IMT base stations in the land mobile service is investigated.
How big of a separation do you need for a UHF antenna?
It is recommended that a minimum horizontal separation of 2m and 4.5m is achieved for UHF to UHF and UHF to VHF installations respectively. On building roof tops where greater horizontal separation is possible 10m is recommended. 2.2.2 Vertical Antenna Separation
Which is a property of the isolation method?
This method has the attractive property of reducing all types of interference. Determining sufficient physical separation is however non-trivial, as the isolation is highly sensitive to antenna choice, heights, azimuths, downtilts and the sectorization angles.