This graph is great but what would be some real world signal levels required? also what would the cut off be -75 -100?
We are looking at testing this against a current LTE Deployment,
Thanks,
A.
Pretty much everything you need is right there... the minimum signal to noise ratio needed is 10dB above the noise floor. I've seen connections down to 7dB SnR however... but I wouldn't install someone at that level.
LTE's lowest usable SnR is typically like around 7 or 8dB... although I have seen some people get a connection down as low as 2dB, it wasn't really usable however.
In LOS situations PMP450 will give you better overall throughput due to 64 and 256QAM being available on the downlink and uplink (LTE is limited to a max of 64QAM on the downlink, and 16QAM and one chain on the uplink, assuming you're using a release 9 eNb, and a CAT4 UE). If you're doing some non/near-LOS shots, LTE might be better due to it having 4 times as many subcarriers (2048 vs. PMP450's 512).
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But whats the signal cut off? with the LTE we can still install a unit at -110 or -100 in the winter
The other number you'd need is the Rx Sensitivity... this is measured differently than LTE equipment, so the numbers won't compare exactly.
For 450 systems, the tables can be found in the User Guide, and the 450i 3 GHz will be the same as that of the 450 3 GHz.
For a 5 MHz channel bandwidth (as an example), the table looks like this:
| SM Rx Sensitivity (Conservative assumption for MIMO-A: large difference between RSSI of two branches) |
-71 | [dBm] | 8X MIMO-B | 256QAM | AP Rx Sensitivity (Conservative assumption for MIMO-A: large difference between RSSI of two branches) |
-68 | [dBm] | 8X MIMO-B | 256QAM |
| -71 | [dBm] | 4X MIMO-A | 256QAM | -68 | [dBm] | 4X MIMO-A | 256QAM | ||
| -77 | [dBm] | 6X MIMO-B | 64QAM | -76 | [dBm] | 6X MIMO-B | 64QAM | ||
| -77 | [dBm] | 3X MIMO-A | 64QAM | -76 | [dBm] | 3X MIMO-A | 64QAM | ||
| -85 | [dBm] | 4X MIMO-B | 16QAM | -83 | [dBm] | 4X MIMO-B | 16QAM | ||
| -85 | [dBm] | 2X MIMO-A | 16QAM | -83 | [dBm] | 2X MIMO-A | 16QAM | ||
| -91 | [dBm] | 2X MIMO-B | QPSK | -90 | [dBm] | 2X MIMO-B | QPSK | ||
| -91 | [dBm] | 1X MIMO-A | QPSK | -90 | [dBm] | 1X MIMO-A | QPSK |
Sorry for the odd formatting.
I can't read any of that, it's too compressed/small. Are the green shaded areas tree cover/obstructions that you've added? If yes, can you describe the trees/obstructions you're trying to get through? I can barely read it, but it looks like the link is less then a kilometer?
you will need to right click the image and open it in a new tab.
Included is the sat view and depending on the software is 1-1.5km away
Hmmm... 1.5km, with a few trees in the way, no buildings or hills in the way? I'd wager that it would be possible. You'll def have to use SM's w/reflector dishes, and maybe even a connectorized SM w/2' dish. How's the noise floor for 900MHz looking like?