Currently I am setting up a 5.8Ghz PTP link over 10km distance and I thought I had a Fresnel-zone issue even the link calculation software results indicted no issues or maybe co-location interference but the frequency scan had all the other items on the mast with signal of 45dbm + but I still repositioned both ends of the PTP in a process of elimination, protocol 802.11a/n with bandwidth 20Mhz the signal using 23dbm gain antennas with R5SHPn radio cards was -61dbm and SNR was 54db but CCQ was at idle going to almost 100% but when I did bandwidth test from a router before and to beyond the link the CCQ drops to 50% or less, I swapped out the antenna with a lower gain and got -70dbm SNR 43db but CCQ on bandwidth testing drops to 16%, I have moved frequency several times and finally I am now using NV2 and this has increased the CCQ under max load to 70%+ but was trying to setup this link to use 802.11N, any suggestions are most welcome on this issue?
Do you have other radios on the same mast that you are now which have their antennas close to you?
If yes, then you MUST move your antenna away from them.
I moved the PTP about 50meters away from this mast and still low CCQ under load on 802.11
If you do a scan there, how high signals do you get?
Cannot recall the numbers but if there were high (between -30 ~-40) then i would have spotted this?
What?..-30 to -40dB?..That’s high M8!
…and yes, if you get high signals from others into your radio, don’t expect to do your job right. 
Do you get these signals at the place that you are now?
If yes, you have to put another antenna to that place with less sidelobes or take a dish and put there.
I said ..if there were high (between -30 ~-40) then i would have spotted this.. but they were not high and certainly not -11dbm as i have read at this site before I applied screening to all AP’s,
A scan on the mast has signals of between -58 to -79dbm
Ohhh…Then your OK… 
I suppose that you have ONLY ONE radio in your outdoor unit at each side ehh?
Could you post a screenshot of the signal/CCQ without bandwidth test and another one with it?