Hi friends:
the Interference test is a test that done on the mobile site to make sure that there is no interference in the received signal in the microwave
This test is done by switching off the transmitter on the transmitter side and turning on the receiver on the other side and measuring the receiving power.
this operation called: Mute ODU in neat end and unmute ODU in far end.
theoretically that when the transmitter is switched off, we shouldn't receive any signal at the receiver
But in fact, we will receive a very weak signal and can be neglected if we receive a signal within -90 dbm.
This means that we do not receive anything , and therefore there is no interference.
But if we receive a high power value. -80 or -70, for example, this means that there is interference, which may increase or decrease the original signal, and it is also possible to release "not error rate"
Fading is a kind of problem that happens to any signal as it passes from transmitter to receiver.
There are many types of fading.
The most important of them at the level of transmission:
Up Fading
Down fading
Slow fading
Fast Fading
Up fading
occurs if the received signal is higher than the received threshold
Down fading
the received signal is lower than the threshold limit allowed reception
Fast fading
is a multipath fading as a result of the signal passing in more than one path and its reflection on more than one barrier then arrive to receiver.
Slow fading
is rain attenuation and due to rain
Thank you.
