What is 0-QPSK? CW?
From: Adam Moffett
Sent: Sunday, September 25, 2016 5:09 AM
To: [email protected] ; [email protected]
Subject: Re: [AFMUG] 900 MHz PMP450i :: Any real numbers?
Undoubtedly true guys, but same thing. Assuming this table comes through, it's
showing you the bottom mod levels on LTE at 10mhz channel size. So yeah, in
theory we could hook up somebody at -100 and it would "work", but you'd be
spending a lot of money to not get much capacity. SCADA might "work" for
George's internet customers in the same sense that scraping the bottom on LTE
would "work".
Modulation and Coding Scheme Max troughtput [Mbps] SINR (dB) Receiver
Sensitivity (dBm)
Minimum by DL/UL split Required SINR at Cell Edge (dB)
DL MCS UL MCS DL UL DL UL DL UL DL UL
0-QPSK 0-QPSK 0.91 Mbps 0.25 Mbps -1.2 dB -1.0 dB -6.7 dB -3.3 dB -106.1
dBm -102.3 dBm
1-QPSK 1-QPSK 1.18 Mbps 0.32 Mbps 0.0 dB 0.1 dB -5.6 dB -2.4 dB -105.1
dBm -101.4 dBm
2-QPSK 2-QPSK 1.45 Mbps 0.40 Mbps 0.7 dB 0.7 dB -4.8 dB -1.6 dB -104.3
dBm -100.6 dBm
3-QPSK 3-QPSK 1.87 Mbps 0.51 Mbps 1.7 dB 1.7 dB -3.8 dB -0.5 dB -103.3
dBm -99.5 dBm
4-QPSK 4-QPSK 2.38 Mbps 0.65 Mbps 2.7 dB 2.8 dB -2.8 dB 0.4 dB -102.2 dBm
-98.5 dBm
5-QPSK 5-QPSK 2.88 Mbps 0.79 Mbps 3.6 dB 3.5 dB -1.7 dB 1.3 dB -101.1 dBm
-97.7 dBm
6-QPSK 6-QPSK 3.38 Mbps 0.93 Mbps 4.6 dB 4.2 dB -0.7 dB 2.2 dB -100.2 dBm
-96.7 dBm
7-QPSK 7-QPSK 4.07 Mbps 1.12 Mbps 5.6 dB 5.3 dB 0.6 dB 3.4 dB -98.9 dBm
-95.6 dBm
8-QPSK 8-QPSK 4.57 Mbps 1.25 Mbps 6.5 dB 6.0 dB 1.5 dB 4.2 dB -97.9 dBm
-94.7 dBm
9-QPSK 9-QPSK 5.24 Mbps 1.44 Mbps 7.6 dB 6.9 dB 2.5 dB 5.6 dB -97.0 dBm
-93.3 dBm
10-16QAM 10-QPSK 5.24 Mbps 1.58 Mbps 7.7 dB 7.6 dB 2.5 dB 6.2 dB -97.0
dBm -92.7 dBm
------ Original Message ------
From: "Colin Stanners" <[email protected]>
To: "[email protected]" <[email protected]>
Sent: 9/25/2016 12:11:30 AM
Subject: Re: [AFMUG] 900 MHz PMP450i :: Any real numbers?
Some SCADA systems run at like 115kbaud with -103db receive sensitivity in a
1mhz channel... that will survive a lot.
On Sat, Sep 24, 2016 at 10:17 PM, Jaime Solorza <[email protected]>
wrote:
Depends on the system.. SCADA type radios have no problem with trees...
On Sep 24, 2016 7:22 PM, "Adam Moffett" <[email protected]> wrote:
Might be worth a shot I guess. Depends how strong your 900 is coming in.
Attenuation is attenuation though...whether it's LTE or something else.
If the path literally passes through a mile of trees then I'm surprised even
900 works.
------ Original Message ------
From: "George Skorup" <[email protected]>
To: [email protected]
Sent: 9/24/2016 3:45:44 PM
Subject: Re: [AFMUG] 900 MHz PMP450i :: Any real numbers?
And what happens when the noise floor increases and the eNB can't hear
those shitty CPEs anymore? Nevermind, that question answered itself.
The boss keeps wanting to try an LTE sector at sites where we have a
mile or more deep trees (where we know 900 FSK barely works now, not only due
to power levels but noise floor too). My fear is that it actually does "work"
(meaning horrible mod levels) and he'll want to run with it. So we'll get what,
a couple Mbps out of a sector. Sounds a lot like 900 FSK. Sounds a lot like 900
450i with a horrible noise floor. So we gain nothing and spent a ton of money.
Great idea. And we won't end up getting all of the customers off of the 900
anyway, that I'm sure.
On 9/24/2016 11:47 AM, Adam Moffett wrote:
In Wimax it's 4x4....I'm pretty sure we'll have 4x4 in LTE as well,
but I think feature was released only a month or so ago. We have a few places
with split sectors, so we'll be able to compare to 2x2.
From what I understand, LTE's frame structure is such that it can
hang on to a crummy signal longer than Wimax. It was explained to me that
Wimax puts the synchronization data in the pre-amble which has to be received
on every subcarrier, whereas LTE has that data interspersed among the
subcarriers, so where your weak wimax CPE sometimes cuts in an out, an LTE CPE
in the same conditions can stay connected. It also has lower mod levels that
let it operate right down to the noise floor. And at least in theory you'll
get more throughput than you get in the same conditions on Wimax.
I have the same reservations as you about the low mod levels thing.
Just because they work doesn't mean you want them. We're not intentionally
installing anything weaker than a -80 RSSI right now, so we really ought to be
ok on that front.
-Adam
------ Original Message ------
From: "George Skorup" <[email protected]>
To: [email protected]
Sent: 9/23/2016 11:23:57 PM
Subject: Re: [AFMUG] 900 MHz PMP450i :: Any real numbers?
Well, let me ask this. Are you doing 2x2 or 4x4 on the Telrad?
Obviously 4x4 would give a slight advantage.
My whole thing is, OK, it might work through a shit ton of trees.
Linked up and able to move some traffic is one thing. But a whole bunch of low
modulation customers on a sector is not worth the investment. LTE, Wimax, 450i
900.. whatever it may be.
I know of a Telrad installation where they couldn't make it work.
Turned out to be interference. They had some guys from Israel come "fix" it. I
won't say any names, but I now see what they did to get it working. It's in the
3.5 band.. because I can see them on my 450's spectrum analyzer. From multiple
sectors on multiple towers, so I know what direction it's coming from. And I
have no doubt they're running it over powered.
Welp, we have a BaiCells demo kit, so we'll see what happens.
On 9/23/2016 9:52 PM, Adam Moffett wrote:
We've had Telrad Compact 1000's for around 2.5 years, but they're
running Wimax firmware because we were replacing older 16e installations. We
have a number of sites now that have entirely dual mode CPE so we're about to
pull the trigger on LTE. We're installing four LTE base stations next week on
brand new sites, and assuming those go well we'll upgrade some existing Wimax
sites.
So yeah, within the next few weeks I'll know more. I'll
definitely report back.
It's interesting that you phrase it as "if it works at all." The
issue with Wimax has never been it "working", it's just that it comes with a
lot of quirks and it sucks at administration and troubleshooting. I'm speaking
of Wimax in general here, not Telrad specifically....and I've used Wimax from
three different vendors now. I have no fear about LTE working. I am afraid it
will turn out to be cut from the same cloth as Wimax.
------ Original Message ------
From: "George Skorup" <[email protected]>
To: [email protected]
Sent: 9/23/2016 8:04:34 PM
Subject: Re: [AFMUG] 900 MHz PMP450i :: Any real numbers?
Aren't you doing Telrad? Please let us know if it works at all.
On 9/23/2016 4:05 PM, Adam Moffett wrote:
I'll let you know in a few weeks.
------ Original Message ------
From: [email protected]
To: [email protected]
Sent: 9/23/2016 5:01:02 PM
Subject: Re: [AFMUG] 900 MHz PMP450i :: Any real numbers?
I wonder what LTE would do with the same RSSI.
From: Adam Moffett
Sent: Friday, September 23, 2016 2:46 PM
To: [email protected]
Subject: Re: [AFMUG] 900 MHz PMP450i :: Any real numbers?
Oh I also have somebody with a -88 who gets about half that.
900 was the last ditch effort for both of these.
With wimax from the same tower we got a big fat nothing at
both locations.
------ Original Message ------
From: "Adam Moffett" <[email protected]>
To: [email protected]
Sent: 9/23/2016 4:44:21 PM
Subject: Re: [AFMUG] 900 MHz PMP450i :: Any real numbers?
On the other end of the quality spectrum:
Link Test with Bridging
VC Downlink Uplink Aggregate Packet Transmit Packet
Receive
Actual Actual
19 6.07 Mbps 1.32 Mbps 7.39 Mbps, 474 pps 821 (410
pps) 128(64 pps)
That's a -85 on a 5mhz channel. On any wider channel I
lose this guy.
------ Original Message ------
From: "Dave" <[email protected]>
To: [email protected]
Sent: 9/23/2016 4:17:36 PM
Subject: Re: [AFMUG] 900 MHz PMP450i :: Any real numbers?
This is from one of ours
Current Results StatusStats for LUID: 3 Test
Duration: 5 Pkt Length: 1714 Test Direction Bi-Directional
RF Link Test
VC Downlink Uplink Aggregate Packet Transmit
Packet Receive
Actual Actual
19 26.13 Mbps 6.78 Mbps 32.92 Mbps, 2367 pps
2389 (477 pps) 9450(1890 pps)
Efficiency
Downlink Uplink
Efficiency Fragments
count Efficiency Fragments
count
Actual Expected Actual Expected
100% 255254 255254 78% 84124 66231
Link Test ran on 03:59:48 01/09/2011 UTC
Currently transmitting at: VC 19 Rate 8X/8X MIMO-B
On 09/23/2016 03:12 PM, Bill Prince wrote:
We're looking at doing a forklift on a couple of 900
MHz FSK APs. What are real world throughput numbers that any of you pioneers
are getting? We would probably want to do 10 MHz channels at first, and I would
hope that we could get > 15 Mbps in download, but maybe I'm being too
conservative?
The places we are looking at do not have Smart Meter
issues.
--
bp
part15sbs{at}gmail{dot}com
--
