Indoor LTE 1800 DAS Antenna Seperation

[redrooster]

Hi All,

Can anyone please help. We have been deploying E******* indoor 1800 GSM and 21000 WCDMA DAS systems which we are now going to converting to LTE1800 :) Is there any information on changes for MIMO? For example:

1/ if we now use two antennas, can I assume we now need two feeds?
2/ Do I need to use a extra combiner (read this somewhere)?
3/ What is the recomended minimum distance between indoor antennas?
4/ Does LTE need less power at the antenna than GSM/UMTS?

Any specifics would be great!

Thanks

[redrooster]

Just moved this thread...anyone here can help me :)

[petitchoe]

Need more information KPI, SU/MU-MIMO, Throughput, Vpol/Xpol antennas...

[kurniadii]

Hi All,

Can anyone please help. We have been deploying E******* indoor 1800 GSM and 21000 WCDMA DAS systems which we are now going to converting to LTE1800 :) Is there any information on changes for MIMO? For example:

1/ if we now use two antennas, can I assume we now need two feeds?
2/ Do I need to use a extra combiner (read this somewhere)?
3/ What is the recomended minimum distance between indoor antennas?
4/ Does LTE need less power at the antenna than GSM/UMTS?

Any specifics would be great!

Thanks

1. Yes, u should be double antenna & feeder, splitter & other, basically is parallel DAS because your config DAS is MIMO 2 X 2
and also you should be keep balance the Loss between MIMO 1 with MIMO 2, i don't know the real acceptable value maximum, i already read in some document is keep the loss don' less 2 dB

2. i don't know the Freq for LTE 1800, but u can read the Existing combiner Spec for 1800 freq range, if your LTE freq range already on range of existing combiner u just can add the power combiner before on port 1800 existing combiner or u can repalce with wide band combiner
as my know the freq range of 1800 GSM is : 1805 - 1880 (downlink), 1710- 1785 (uplink), if same freq i think will be interference if u use the same DAS, so if your LTE freq range still same range with 1800 GSM, so your GSM1800 & LTE should be different DAS

3. antenna separation minimum is 2 to 3 wavelength but TE recommendation is 6 wavelength, for alternative if u difficult u can use dual pol omni antenna :
http://www.te.com/content/dam/te/global/english/industries/wireless-adc/knowledge-center/documents/distributed-antenna-systems-and-mimo-technology-109936AE.pdf

u can read also on : http://books.google.co.id/books?id=ljSs8-bGylIC&lpg=PP1&hl=id&pg=PA155#v=onepage&q&f=true

4. what you mean of power at the antenna ? the EIRP ? i think if EIRP is depend on your target RSRP

Note : actually i am not yet experiance for LTE, but just read of some LTE document

thanks