vkurani31

Lets see... lets see..

 

- 20+20+20 or 3 carrier aggregation is not yet finalized in software testing or field implementation. All three vendors must be completely done with all field testing before they start doing a nationwide staggered rollout. 

 

- Not all spectrum is free. WiMax is still holding a substantial amount of spectrum up as they did tend to love using different frequencies on each sector. 

 

- Backhaul is a substantial issue with things as it stands. A good portion of 2.5 sites still lack upgraded backhaul to enable a second carrier and forget about a third.

 

- Sprint sites are not all designed to max out every single available piece of spectrum. Backhaul is pricey especially when you need upwards of 2+ gigabit per site. 

 

Most standard 2.5 sites will have 3 carriers deployed at any time. At the highest usage sites they will add more B41 carriers and that is known as a high capacity site. It'll be 40+40 or 60+60  and they have the option to virtually split the sectors and the antenna into 4T4R so 6 sector B41 sites. Each "chain" maxes at 60 MHz or 20+20+20 (3x20) x 2 chains (total 120 MHz maximum). 

 

TLDR: NOT READY YET. 

Thank you TIm !

I believe 3xCA/4xCA requires testing, just like every other thing that is rolled out. And also the backhaul requirements are there, too. Having 3xCA or 4xCA, one or two 5 MHz Band 25 carriers (maybe one 10 MHz and one 5 MHz carrier), a 5 MHz Band 26 carrier, and several carries of 1x and EVDO, on 3 different sectors really adds up in the amount of backhaul required. A lot of sites probably just don't have enough backhaul yet to support it.

 

There are other people on the site, such as Tim or Robert, that are much more knowledgeable on the subject than I am, so don't just take my word for it. I'm sure they will chime in soon.

 

-Anthony

Thanks for your response. From what i understand they are doing it in waves, first go for 2x20 then move on the three CA. I agree they would need the required backhaul to support this, but i think doing it in waves just adds the additional costs. But yes if the backhaul is not available, no point of adding it

I understand sprint is in the middle of adding 2xCA on 2.5GHz. If I am not wrong, sprint has on average 120 Mhz of spectrum in the 2.5 GHz band in 90 of the top 100 U.S. markets.

2.5 Ghz may not propagate far but the spectrum is excellent for capacity. 

Instead of deploying 2x20, why not roll out 3x20 and if i am being way too optimistic 4x20. Kill the competition basically and make you use of this large swath of spectrum now, instead of doing it in pieces while the competition zooms past them.

What is stopping them to do so ?

What are are the technological challenges to deploy 2x20, 3x20 simultaneously ?