More on SA cell towers

It looks like some sort of array antenna, dipole or patch. What it is for I don't know. From the size I'm guessing it is somewhere around 4-5GHz. Unfortunately without getting a closer look we won't be 100% sure.
 
Rickster said:
This is semi related, when I tun my phone upside down I instantly get better signal, ive done this with a couple of phones and each time it works, any reason why?
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It is normal. Antenna is located on the opposite side to the earpiece. When you answer the call and put handset to your ear, the main signal beam goes to the air, not your head. It is typical design to reduce radiation, exception is Apple iPhone which has antenna on the metal bracket around the phone, terrible reception figures and high SAR.

I see you have already received different answers to your question (and contrary to this answer). :)
 
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SauRoNZA said:
What's that square one pointing towards the right?

Almost looks like a satellite based M2M antenna but the angle is a bit off for that.
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Apparently the small square antenna is also microwave.
 
Here's a quick one from an outing today. The weather was very wintery and light was poor so I didn't unpack my DSLR (f/4-5.6 so best for full sun).

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Located at yet another Total service station in Rangeview off Robert Broom Drive.

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Compact site.

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Obligatory warning signs for the people scared of cell tower radiation. :p

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I couldn't see any sign of other cell operators sharing the site.

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Super neat BTS shelter.

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The same refrigeration company as per my first photo shoot.
 
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I hate these 'camo' sites. You cannot see any equipment! Unfortunately all the newer, smaller sites are like this.

So this particular base station hasn't been upgraded to LTE. I surveyed last week and there's only 3G (rather fast 3G mind you).

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I found yet another camo base station after this with no BTS shelter in sight. (?!) Dusk had set in so I'll have to go back for a better look another time.
 
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jcheek said:
Here's another pic which is kinda interesting ... it relates to the same base-station as in this post.

Cell C were one of the subsequent "shares" on this original Vodacom site and their gear is interesting because it's relatively compact - all the other players have containers or enclosures - and it's also mounted on a pole out in the open :

View attachment 139042

More Kathrein equipment. This time it's one of their triple-band combiners/triplexers. Here's a right-way-up close-up :

View attachment 139044

If you look closely you can see what seem to be the "input" ports for GSM900 (Port1), GSM1800 (Port2) and UMTS/3G (Port3), all being combined and going out on one output port (Port4). Perhaps this feeds up into some sort of Tower-Mounted Amplifier and thence to some sector antennas ?

Maybe someone else in the industry can chip in with more detail ?
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I don't have experience with these types of setups, so this is just my 2c.

Tower mounted amplifiers would be nice, since it minimises the you then don't amplify the signal before sending it along a long coax cable to the sector antenna.

There are a couple of issues that I do see with such a setup. I don't know if they will combine the different bands before amplifying them. The reason why I say this is twofold: First, linear broadband amplifiers are expensive. Really expensive. Especially at the output power for cell base stations. It might be more cost effective to have separate amplifiers for each of the bands, as these lower bandwidth amplifiers are a bit cheaper.

The second issue might be with the legislation covering these frequency bands. The specified transmitted power might be different for the different frequency bands. I am no expert on this, it is only an assumption.

If there is someone with better insight, please enlighten us.
 
Azimuth said:
View attachment 133967

VjYi5uX.jpg

All the sector antennas seem old yet this site was upgraded within the past year to 100Mbps LTE.
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MTN is reusing the the GSM 1800 Antennas for LTE 1800 rollout. So 1 antenna emitting LTE and GSM. This is why the unit looks "old".

Also, please note that 2G and 3G do not use the same antenna unless the same band is used for 2G and 3G. That said, there are a lot of tri-band antennas, so 900, 1800 and 2100mhz in one unit.
 
I've since been told but thanks for confirming SteveO! Any other information you can share with us? :cool:
 
To get LTE on an existing GSM/3G tower do they only have to change the antenna or must they upgrade the fiber links underground as well?
 
jcheek said:

Along with some from a much older name - Kathrein:
View attachment 138968
From what I can gather, that Kathrein "Remote Control Unit" inline box plugged into the right-hand port might have something to do with allowing the antennas to be tilted remotely ... ?
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Yes, thats a RETU - Remote Electrical Tilt Unit

Allows the antenna to be tilted remotely from the NMS (Network Management System)
 
Azimuth said:
What is the use case for this?
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Basically saves a lot of time in terms of optimising the network. Without a RET a rigger would need to visit the site, adjust the tilt manually (involves climbing the tower and in some cases shutting off the site) so safe to assume a day to have this done. With RET its literally 5 minute activity with no downtime.
 
Sorry, I meant from the consumer side (your above post is still plenty useful!) :)
 
Azimuth said:
I assume the RRU's need to be upgraded at least?
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Yes, it depends on the vendor and the frequency band.

Mostly its just the addition of LTE RRUs here in SA as most of the LTE rollouts are being done using 1800 or 2100 mhz.

Secondly, microwave is also used to a large extent. Most are capable of around 1Gbps + depending on the configurations used.
 
So the antennas without RRU's are GSM only?

Are you saying microwave is added for a separate LTE backhaul?
 
AntennaMan said:
I don't have experience with these types of setups, so this is just my 2c.

Tower mounted amplifiers would be nice, since it minimises the you then don't amplify the signal before sending it along a long coax cable to the sector antenna.

There are a couple of issues that I do see with such a setup. I don't know if they will combine the different bands before amplifying them. The reason why I say this is twofold: First, linear broadband amplifiers are expensive. Really expensive. Especially at the output power for cell base stations. It might be more cost effective to have separate amplifiers for each of the bands, as these lower bandwidth amplifiers are a bit cheaper.

The second issue might be with the legislation covering these frequency bands. The specified transmitted power might be different for the different frequency bands. I am no expert on this, it is only an assumption.

If there is someone with better insight, please enlighten us.
Click to expand...

Everything is amplified either in the cabinet or at the RRU.

You are right in that the TMA almost negates attenuation losses from the "long" coaz (feeder) However it only amplifies the UL signal. What is being achieved with a TMA is to allow the (weaker) signal your phone is sending to site to be amplified before it is attenuated via the feeder. TMA is essentially a LNA and not a PA, which is used in the RRU/RU
 
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