Co- & adjacent channel interference

hi rimi,

as you know, one call is using one specific frequency during one/eight of the time.
if somewhere else in the area, another call is using the same frequency during the same time, the first user will hear a degradation in the voice quality (robot voice).

this is co-channel interference.
2 calls using the same frequency, in the same area.
if there are 8 users on the first frequency, and 8 users on the second frequency, you see that the probability of “collision” is very high.

now, same scenario, except that the second user is using a frequency which is +200kHz or -200kHz compared to the 1st frequency. Here, the impact on the voice is much less : only if this “adjacent” frequency is very very strong, then the first frequency will be “eclipsed” and the first subscriber will hear a bad voice quality (still the robot voice).

the cell doesn’t identify the interference, it is up to the optimizer to find which frequencies are conflicting.

cheers
pix

by checking which cells are using the same frequency in the vicinity, on the map, and trying to guess which one is actually propagating up to where the intereference was detected.

regards
pix

hi,

this is what i’ve explained in my previous post..