BAD Link Test

Stats for LUID: 5 Test Duration: 10 Pkt Length: 1522
Downlink RATE: 768000 bps
Uplink RATE: 239974 bps
Downlink Efficiency: 17 Percent
Max Downlink Index: 92
Actual Downlink Index: 16
Expected Frag Count: 15000
Actual Frag Count: 91931
Uplink Efficiency: 97 Percent
Max Uplink Index: 97
Actual Uplink Index: 94
Expected Frag Count: 4687
Actual Frag Count: 4954


We get a few complaints from this customer from time to time about Ping Times. I have noticed the last couple of times that their jitter will bounce from 2 to 12 constantly, while the dBm stays constant -60 and the RSSI does to 1220 to 1227. What would/could cause the Jitter to bounce so much and be so high at times? What should I actually look at when doing a LINK test that would indicate an issue?

-j

I have ran into this as well, decent dmb level and 100 uplink with a 7 percent downlink. swaped sm and still the same thing

I would suggest running a spectrum analysis at the customer location to check for potential interference. You also may want to check the alignment of the SM, validate that it is locked down and not moving.

Just reading your post, my recommendation would be to check for cordless phones, but also check BEHIND the unit, remember that the fresnal still goes PAST the unit, and PAST the tower. There might be some tin or something in behind the unit, or behind the tower. Also, if you have multiple AP’s up on the tower, try putting the unit into alignment mode and see if the sm is switching AP’s. If so, remove frequencies that show poor jitter. Let me know how it goes!

Daveamd

Are you saying metal behind a SM could cause problems? I have one client who has good dbm and rssi but bad jitter. The SM is mounted infront of his solar array of 16 plus solar panels.

Do you think this could be causing a problem? How high would I have to raise the SM to eliminate issues?

adamb

We have a customer who has those metal shingles and we noticed that he would experience a spike in jitter. (12-15) We tried moving the SM (900) up on the top ridge but did not help. We ended up spliting the difference, therefore it was 5 feet above the lower metal roofline, and 3-4 below the top ridge. This seemed to solve the high jitter.

Z