dslreports logo
 
    All Forums Hot Topics Gallery
spc
Search similar:


uniqs
4300

quetwo
That VoIP Guy
Premium Member
join:2004-09-04
East Lansing, MI

quetwo

Premium Member

New AT&T / Cingular Tower

Click for full size
Picture of the AT&T Doghouse (aka the Cow)
Click for full size
The 100ft tower. 12 antennas in 6 features off 3 posts. 3 GSM and 3 3G
Click for full size
temporary cement work to keep the tower up
Click for full size
CO grade batteries
Click for full size
DC rect and GSM antenna cabinet
Click for full size
UTMS antenna systems
Click for full size
T1 terminating equipment (Acatel/Lucent)
Click for full size
antenna connecting equipment for GSM
AT&T is in the process of setting up a DAS system on our campus (Distributed Antenna System), but since the paperwork was taking a long time, they decided to deploy a temporary 100ft tower on our campus to get through this semester.

When they are finished, they will have 24 micro-cells on our campus (3 miles wide, 9 miles deep, but only 3x3 are going to be covered).

The attached are of the temporary tower and doghouse that they are deploying right outside my window. They have a temporary 100pair cable running from our basement going to the doghouse, holding about 50 T1's. This tower will service GSM and UMTS service, and should give moderate penetration on our campus.

They just started digging the foundation of their real doghoue that will feed the DAS antennas. Our campus is providing the fiber to interconnect the antennas, but they are installing in locations both of us agreed to. Like the other 6 vendors on our campus, you won't be able to see them from the ground, or really know where they are unless you work for my department. All the vendors install antennas on our roofs to painted to match, and often are confused for ventlation.
drslash (banned)
Goya Asma
join:2002-02-18
Marion, IA

drslash (banned)

Member

Michigan State University?

Cjaiceman
MVM
join:2004-10-12
Castle Rock, WA

Cjaiceman to quetwo

MVM

to quetwo
I hope they put that 3G (UMTS) on the 850MHz band...

quetwo
That VoIP Guy
Premium Member
join:2004-09-04
East Lansing, MI

quetwo to drslash

Premium Member

to drslash
Yup.
cooldude9919
join:2000-05-29

cooldude9919

Member

So is that how they do 3g in some towers where they cant get anything more than t1's? They just do ~50xt1?
Hahausuck
Premium Member
join:2003-12-14

Hahausuck to quetwo

Premium Member

to quetwo
So nice to see a cable lace job instead of zip ties.

quetwo
That VoIP Guy
Premium Member
join:2004-09-04
East Lansing, MI

quetwo to cooldude9919

Premium Member

to cooldude9919
Most locations are not enabled for DS3 or higher. They just run lots and lots of T1's to a MUX to get the bandwidth there.

Each site is different as to how much bandwidth they need.

kewlkeed
Grouch
Premium Member
join:2005-02-05
Knowlton, QC

kewlkeed to quetwo

Premium Member

to quetwo
Hehehe I was gonna comment on some messyness but it's a temp install... In that case anything goes
zencyl
join:2009-07-24
Huntsville, TX

zencyl to quetwo

Member

to quetwo
ok im a complete newb. When you said "When they are finished, they will have 24 micro-cells on our campus (3 miles wide, 9 miles deep, but only 3x3 are going to be covered)." does that mean they are going to bury some type of loop antenna 9 miles deep or am i totally missing what was being said? Thanks.

kewlkeed
Grouch
Premium Member
join:2005-02-05
Knowlton, QC

kewlkeed to quetwo

Premium Member

to quetwo
No he means the campus is 3 miles by 9 miles... But they are only gonna cover a 3x3 mile square area of it.

(With 24 micro-cells, that seems to me to be a MASSIVE overkill I would think though? Someone correct me on this please. Unless you're counting every antenna as a "cell" but most of the time here it's the tower itself that basically is referred to as a "cell"... Yes perhaps bad terminology but it's what the techs here say. I would assume you don't have 24 tower/base sites such as this one above on a single campus.)

quetwo
That VoIP Guy
Premium Member
join:2004-09-04
East Lansing, MI

quetwo

Premium Member

No, we will have 24 micro-cells. These are essentially "towers" that are affixed directly to the building roof, or having 1ft antenna masts. These "towers" will have 2 antenna elements (one for UMTS and one for GSM). The large tower that was built (and photoed) is a temporary install only, and does not represent the rest of the install.

On our campus, we need a higher density than a typical area. On any given day, we have a population of about 80,000 people on our campus, and on football / basketball game days we host > 120,000 people. While most of these people won't have an AT&T phone, we are still planning for saturation numbers.

Cjaiceman
MVM
join:2004-10-12
Castle Rock, WA
(Software) pfSense
Ubiquiti UniFi UAP-AC-PRO

Cjaiceman

MVM

Considering how popular the iphone is, and how many college students have one, this is a good plan. I know when I go to a baseball game or football game here in Denver, the 3G is useless, I can't make or receive any calls, and the data is so unstable the IM clients won't even stay connected, not to mention that mms won't work either. I just switch my TyTN II back to edge and everything works, so I could easily see how a lot of phones could eat up a couple towers.

kewlkeed
Grouch
Premium Member
join:2005-02-05
Knowlton, QC

kewlkeed to quetwo

Premium Member

to quetwo
Holy christ... Yeah that's a load for sure. Wow.

k9snifferxx3
Don't sweat the small stuff.
Premium Member
join:2006-03-04
Calgary, AB

k9snifferxx3 to quetwo

Premium Member

to quetwo
said by quetwo:

No, we will have 24 micro-cells. These are essentially "towers" that are affixed directly to the building roof, or having 1ft antenna masts. These "towers" will have 2 antenna elements (one for UMTS and one for GSM). The large tower that was built (and photoed) is a temporary install only, and does not represent the rest of the install.

On our campus, we need a higher density than a typical area. On any given day, we have a population of about 80,000 people on our campus, and on football / basketball game days we host > 120,000 people. While most of these people won't have an AT&T phone, we are still planning for saturation numbers.
You have me curious, How many phones can a single cell site handle?
Hahausuck
Premium Member
join:2003-12-14

Hahausuck

Premium Member

I believe that is dependent on the number of T-1's per site, if you will.

A T-1 can handle 24 calls, provided the rest of the channels are not being used for other purposes like data. Then it is a matter of oversubscription. Traffic engineering is used to determine actual loads and predicted loads, so that the carrier can plan sufficiently for upgrades.

Someone correct me if I am wrong, but that is my understanding of it.

k9snifferxx3
Don't sweat the small stuff.
Premium Member
join:2006-03-04
Calgary, AB

k9snifferxx3

Premium Member

Hi AMD Phreak,

I was aware of the T-1 bandwidth issues... The part I am more curious about is the antenna side of things. How many phones can 1 Antenna deal with.

Regards

Joshb

Killa200
Premium Member
join:2005-12-02
TN

Killa200

Premium Member

Depends on the assigned channel space for the site and the tech they are using
Hahausuck
Premium Member
join:2003-12-14

Hahausuck to quetwo

Premium Member

to quetwo
The antenna is just an antenna, it just radiates the RF energy produced by the Base Station.

The number of calls is defined by the stuff in the shelter.

Splitpair
Premium Member
join:2000-07-29
Cow Towne

Splitpair to Hahausuck

Premium Member

to Hahausuck
said by Hahausuck:

I believe that is dependent on the number of T-1's per site, if you will.

A T-1 can handle 24 calls, provided the rest of the channels are not being used for other purposes like data. Then it is a matter of oversubscription. Traffic engineering is used to determine actual loads and predicted loads, so that the carrier can plan sufficiently for upgrades.

Someone correct me if I am wrong, but that is my understanding of it.
Consider yourself corrected.

A T1 actually a DS1 (once it is handed off to the customer) if channelized out at 64K will only transport 24 calls and if it is a primary rate ISDN that number drops to 23 calls as the D channel requires a single 64K channel to handle call setup and teardown.

However in the non-analog PCS and cellular world the DS1’s can carry considerably more calls than a channelized DS1 due to the encoding of the analog voice at the handset before hitting the RF and in turn the subsequent decoding at the MTSO.

This is one of the reasons calls over wireless many times have the quality of two cans connected by a string.

Wayne
Hahausuck
Premium Member
join:2003-12-14

Hahausuck to quetwo

Premium Member

to quetwo
Thanks Wayne. I figured they used some kind of extra compression and what not to pack more than the standard 24 (or 23 if PRI is transport). The horrible audio quality makes sense too.

Of course there is no excuse for the such horrible performance of the ATT wireless network, with the dropped calls and all, especially embaressing...