LTE 20M vs LTE CA 2x10M?


#1

Hello dear experts,

What do you think the best strategy to deploy one 20M LTE carrier or two 10M LTE carrier and benefit from CA?

In which case I got higher real throughput ?

Thanks in advance.


#2

Obviously, it will be the 20 MHz LTE carrier.
Saves you on the overheads and you get better utilization, UE and cell throughput.
But, it is not easy to find contiguous 20 MHz spectrum.
So, operators explore intra-band and inter-band CA to muster an aggregate bandwidth of 20 MHz.


#3

Another good reason for 20MHz: not all UE’s allow CA.
Even tought that I do not know a case were Intra-band CA would not be allowed.
But I know cases like Xiaomi UE’s that support some bands (e.g. B1, B3, B7, B20) but don’t allow CA between them…
Best performance with less wasted resources is with one block.


#4

Not everyone have the luxury to have 20 MHz, in that case you will need to use 10MHz +10MHz.
There are some advantages to have less bandwidth, two of the biggest ones are coverage and more PUCCH resources. Your peak throughput is slightly lower than single 20 MHz especially when UE is not in CA active.


#5

Now I’m curious, how you improve coverage by splitting bandwidth, keep in mind that in that case you also split the power? (Same PA, same limits. E.g 1x2OMHz/40W or 1x10MHz/20W + 1x10MHz/20W). I just don’t get it…


#6

When you reduce BW the coverage improves, because the RX sensitivity improves.


#7

Indeed, i’ve overlooked the fact that sensitivity changes (difference to 2G, 3G). Thanks for pointing that out.