900 mhz SM, freaking out

SO I have an SM, Im pretty sure the issue is metal siding.

Its mounted about 2 feet away from the siding, about 30 degrees off parallel from the house.
The AP is only 735 feet away, its an 11.5dbi MTI omni. So its way overpowered.

I had turned the the SM power down to 3 (pre v9) and it just wouldnt stay up, I ended up having to point the radio up about 45 degrees to get the recieve at the AP in the 70s, in line with rf balancing.

Session Status : REGISTERED VC 27 Rate 2X/1X
Session Uptime : 00:00:14
Registered AP : 0a-00-3e-94-45-30
Power Level : Actual: -57 dBm Min: -61 dBm Max: -56 dBm
Jitter (Interference Level) : Actual: 5 Min: 3 Max: 7
Air Delay : 5 approximately 0.14 miles (735 feet)

LUID: 011 - [0a-00-3e-94-50-11] State: IN SESSION (Encrypt Disabled)
Site Name :
Software Version : CANOPY 9.4.2
Software Boot Version : CANOPYBOOT 1.0
FPGA Version : 061808 (DES, Sched, US/ETSI) P10
Session Timeout: 0, AirDelay 6 (approximately 0.17 miles (882 feet))
Session Count: 169, Reg Count 109, Re-Reg Count 60, Session Uptime 00:00:25
Jitter (Avg/Last): 4/5 Power Level (Avg/Last): -71/-71
Sustained Uplink Data Rate (SM): 20000 (kbit)
Uplink Burst Allocation (SM): 500000 (kbit)
Sustained Downlink Data Rate (SM): 20000 (kbit)
Downlink Burst Allocation (SM): 500000 (kbit)
Low Priority Uplink CIR (SM): 0 (kbps) Low Priority Downlink CIR (SM): 0 (kbps)
Rate : VC 27 Rate 2X/1X

Radio StatisticsTransmit Unicast Data Count : 1733
Transmit Broadcast Data Count : 104
Receive Unicast Data Count : 1583
Receive Broadcast Data Count : 71752
Transmit Control Count : 124
Receive Control Count : 45
In Sync Count : 408
Out of Sync Count : 390
Overrun Count : 0
Underrun Count : 0
Receive Corrupt Data Count : 0
Receive Bad Broadcast Control Count : 0
PLL Out of Lock Count : 0
Old Version Beacon Received : 0
Wrong Frequency Beacon Received : 1861
Non Lite Beacon Received : 0
Unsupported Feature Beacon Received : 0
Unknown Feature Beacon Received : 0
TX Calibration Failures : 0
Bad In Sync ID Received : 0
Temperature Out of Range : 0
RSSI Out of Range : 0
Range Cap Enforced : 0
Rcv LT Start : 0
Rcv LT Start HS : 0
Rcv LT Result : 0
Xmt LT Result : 0

RF Control Block Statisticsinoctets Count : 6683004
inucastpkts Count : 2323
Innucastpkts Count : 83685
indiscards Count : 0
inerrors Count : 0
inunknownprotos Count : 0
outoctets Count : 713856
outucastpktsCount : 1839
outnucastpkts Count : 146
outdiscards Count : 3
outerrors Count : 0

Total Packets Overload Count : 3
Ethernet In Discards : 0
Ethernet Out Discards
(Statistics=>Ethernet=>outdiscards count) : 0
RF In Discards : 0
RF Out Discards
(Statistics=>Radio=>outdiscards count) : 3

Im assuming this is metal related multipath, but If anyone sees something Im missing let me know.

We have an indoor subscriber unit in for this guy now, but with it being a metal sided house, I think its going to fail

In Sync Count : 408
Out of Sync Count : 390

is this an indicator of multipath?

now im noticing, which I havent before the didstance is showing anywhere between 700 and 1500 feet

Wrong Frequency Beacon Received : 1861

Looks like interference at the SM side.
Have you done a spectrum analysis on SM side with AP off?
Does the customer have any kind of baby monitor, 900mhz phone system, and any other sort of 900mhz equipment.

I assumed that was an issue related to multipath as well.

Its so close to the AP that a spectrum is not worth it, Its a block away.

But I will check with the customer on that.

Now, what about baby monitors, etc, how far will that signal travel? ie, if its a neighbors.

Since this is a metal sided house, If I was able to get a good shot off the AP say through a window, the house itself would act as an RF shield to the outside interference, is this correct?

There was an ISP serving 900mhz waverider gear on a different channel, to one sub on the edge of town here when we deployed the AP, but its gone now as far as I know.

Hows the spectrum?

replaced it with an indoor unit and its all giggles now

nucoles wrote:
Wrong Frequency Beacon Received : 1861

Looks like interference at the SM side.
Have you done a spectrum analysis on SM side with AP off?
Does the customer have any kind of baby monitor, 900mhz phone system, and any other sort of 900mhz equipment.

A little insight on the wrong frequency beacon received counter. This was provided by a Motorola employee on WISPA's motorola mailing list. Essentially, all it is is a counter saying it received an AP beacon while it was scanning on another frequency.

On your SMs you have a checklist of the different frequencies to scan on. If your AP is on 906 and the SM is scanning on 907-924, if it hears a beacon from the AP at 906, it will increment the counter.

Of course, this counter is really going to only increment when the SM is scanning, so if it's extremely high and your reg counts are a little out there, it's just another indication of a problem. As was pointed out, it was a multipath issue in Steve's case.

so it only increments while scanning? Or does it increment other times as well?

My understanding is it should only increment when scanning. I could be mistaken on this.

However the long and the short as it’s really just an informational counter.

i’m sure you have multipath from the metal, we’ve got LOTS of customers in metal buildings and the 900 was a pain to get to work correctly, all of our 900 gear is H pol now and that help a TON to clean out the multipath from metal plus devices like baby monitors are usualy V pol so it helps with that some also.

we mount all of our 900 gear on 30inch J pipes with intergrated radios and so far no real problems, some cases we used a tripod and got a yagi and a 900SMC radio up 5 or 6 feet but never needed to go more, also we stoped using omni’s completely and that seemed to make a diffrence on our jitter, and a MAJOR improvement on power levels, we have customers 2 miles out in a high 50’s with some tree’s on our old 11 db V pole omnis these same customers were in the low 70s range (and it really sucked to change all the customers to H pole from V pole lol )