Hello folks. I have 3 900MHz APs with sector antenna on them. All three running 8.2.7. Works very well. I have a potential customer at 13.8 miles. Signal is very weak:
Signal level from SM (on 24’ pole). (oh yah - running 8.2.4 new - out of the box) RSSI average 1250, jitter 3-4, power level - best I could get was -84. This was using M2 14dbi. HOUSE WITH METAL ROOF. I was testing on the ground beside the house. The metal roof was behind the wireless link, if that makes sense. I tried moving around - there are some trees. These specs are as good as I could get it with the equipment I had to test with.
Here is my question: I have my MAX RANGE set to 14 miles on all APs. Should I increase this some or try again with newer firmware on the SM, or again with a Hyperlink mesh, or M2 17dbi?
One more thing - what effect will having to much downtilt on the AP antennas have? I think I may them tilted down a little more than needed. I figure my signal will eventually lose height over distance. That may be my whole problem with the above test.
Cheers. Back out into the cold.
If you were able to get the SM to register than the Max Range setting should have no effect on your link. My experience with it has been that it will not register if it is beyond the max range of the AP.
As for suggestions - try a higher gain antenna (17db M2, for instance). You should see 3db improvement on the link.
What is the power level of the SM at the AP? That is usually the value I worry about the most.
If I’m well below my noise floor at the AP, then the signal level at the SM usually doesn’t matter too much.
I’ve got rock solid links with SM levels of -82-85 and a reading at the AP of -70.
More gain and elevate the SM
wifiguy wrote:
I've got rock solid links with SM levels of -82-85 and a reading at the AP of -70.
Sorry to interrupt, but -82-85 is not a good rock solid signal. You should think on -70 to -60 to have rock solid signal.
On 900MHz and at those distance tilting it 5Deg. is not a big issue.
If you have NLOS, try a lower gain antenna, not a higher gain. What you will look for is reflected signals not re-bounce signal back ( RADAR ).
This is a week Signal
Software Version : CANOPY 8.2.2
Software Boot Version : CANOPYBOOT 1.0
FPGA Version : 092707 (DES, Sched, US/ETSIv1.3.1) P10
Session Timeout: 0, AirDelay 1916 (approximately 53.34 miles (281652 feet))
Session Count: 1, Reg Count 1, Re-Reg Count 0
RSSI (Avg/Last): 1231/1215 Jitter (Avg/Last): 4/4 Power Level (Avg/Last): -80/-81
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 18 Rate 2X/1X
ridnet wrote: [quote="wifiguy":1ysxrr2g]
I've got rock solid links with SM levels of -82-85 and a reading at the AP of -70.
Sorry to interrupt, but -82-85 is not a good rock solid signal. You should think on -70 to -60 to have rock solid signal.
On 900MHz and at those distance tilting it 5Deg. is not a big issue.
If you have NLOS, try a lower gain antenna, not a higher gain. What you will look for is reflected signals not re-bounce signal back ( RADAR ).
This is a week Signal
Software Version : CANOPY 8.2.2
Software Boot Version : CANOPYBOOT 1.0
FPGA Version : 092707 (DES, Sched, US/ETSIv1.3.1) P10
Session Timeout: 0, AirDelay 1916 (approximately 53.34 miles (281652 feet))
Session Count: 1, Reg Count 1, Re-Reg Count 0
RSSI (Avg/Last): 1231/1215 Jitter (Avg/Last): 4/4 Power Level (Avg/Last): -80/-81
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 18 Rate 2X/1X[/quote:1ysxrr2g]
That is a weak link, but it's also the signal level at the AP (the session status page). The -80 readings I am referring to come from the SM's configuration page. They are two completely separate values. The SM config page shows how well it can hear the AP. The session status page on the AP shows you how well it can hear the SM.
wifiguy wrote:
That is a weak link, but it's also the signal level at the AP (the session status page). The -80 readings I am referring to come from the SM's configuration page. They are two completely separate values. The SM config page shows how well it can hear the AP. The session status page on the AP shows you how well it can hear the SM.
I don't want to make a big deal of this, but -80 on one side and -70 on the other is a week link. A signal of -80 on one side and -60 on the other is still consider a weak link, the problem is the -80. Try to get a symmetrical link -70/-70.
If you have a bad link in the chain the link will eventually break.
But, if it works, and it always works then you have a rock solid link, hope this is in a rural zone.
ridnet wrote: [quote="wifiguy":3ic9irb0]
That is a weak link, but it's also the signal level at the AP (the session status page). The -80 readings I am referring to come from the SM's configuration page. They are two completely separate values. The SM config page shows how well it can hear the AP. The session status page on the AP shows you how well it can hear the SM.
I don't want to make a big deal of this, but -80 on one side and -70 on the other is a week link. A signal of -80 on one side and -60 on the other is still consider a weak link, the problem is the -80. Try to get a symmetrical link -70/-70.
If you have a bad link in the chain the link will eventually break.
But, if it works, and it always works then you have a rock solid link, hope this is in a rural zone.[/quote:3ic9irb0]
You ALWAYS take your noise floor into consideration. I have links like this in a handful of places - the noise floor at the SM side is somewhere between -90 and -100. 20db of fade margin on both ends is a solid link.
“Try to get a symmetrical link” ??
If both sides have antennas with similar VSWR and same TX power level then how will you do that?
The fact of the matter is that the calibration across Canopy radios can vary by 10dB. Motorola confirms this.
twinkletoes wrote: "Try to get a symmetrical link" ??
If both sides have antennas with similar VSWR and same TX power level then how will you do that?
The fact of the matter is that the calibration across Canopy radios can vary by 10dB. Motorola confirms this.
You can control the output power on the radios, You can also attenuate, connectorized version.
Don't know what Moto is up to, but WiMax will adjust the power levels automatically, I think that's what Moto wants to do with the Canopy series.
We are talking about the 900MHz!
This is a “rural” setup. There are 4 towns all within a 20 mile radius, but all have less than 1000 people, except the town where my tower is. I have several 900 customers with stable links at -80 or -82. Noise level is like -95 or less.
About my original post - I’m shooting over my town on 180’ tower. The town is about 3 miles across) then it goes rural with farmland - only trees are in fence rows and next to houses. I have customers on all three APs as far out as 13.5 miles. (That is why I asked about the 14 mile MAX RANGE setting.
I have some 15db grid antenna ordered - will try them soon. I have read that sometimes they perform better than M2 yagis.
Good night.
ridnet wrote: [quote="twinkletoes":1znrlonz]"Try to get a symmetrical link" ??
If both sides have antennas with similar VSWR and same TX power level then how will you do that?
The fact of the matter is that the calibration across Canopy radios can vary by 10dB. Motorola confirms this.
You can control the output power on the radios, You can also attenuate, connectorized version.
Don't know what Moto is up to, but WiMax will adjust the power levels automatically, I think that's what Moto wants to do with the Canopy series.
We are talking about the 900MHz![/quote:1znrlonz]
I think you have unrealistic goals if you expect "symmetrical links", especially when your noise floor in both locations are different.
Regardless, it definitely would be nice if Moto could make the Canopy units automatically adjust their transmit power like the OFDM PTP line does. It would certainly save on a lot of fuss when it comes to having to adjust power levels on hundreds of SMs twice a year.
jakkwb- how long exactly is this link you are attempting to make? The 15db works great when going through more foliage than usual, but you probably won't see much better results, possibly worse than an M2 17db on a long link. We saw the most success in situations where the customer was between 2 and 6 miles from the AP through thick trees. They were borderline with the M2 but the parabolic improved the link by about 7-10db on the AP side. It was literally a night and day difference in those situations.
If it happens to be a long link you are having trouble with - the other solution you could look at is the M2 stacking kit. You'll need to adjust your TX power accordingly to stay within FCC regulations, but the extra gain might help stabilize the link. Being rural this isn't always as critical because there is less chance you are going to interfere with another player, but it's always smart to do things legally and to be a good wireless citizen.
It is almost 14 miles - 13.8.
I’d recommend you stick with the M2 and look at the possibility of using a stacking kit. The 15 probably will gain you nothing at that distance.
You should only need to adjust that max range value if you cannot get the SM to register at all (ie it will keep syncing but never say registered or establish a link).
I also agree with Jerry that you need more height at the SM.