RS POWER

[ulhwbest]

Dear Experts,
In Huawei LTE, how can we distinguish the limitation on setting the RS Power? Is it based on eNodeB Type?
For example, small cell maximum is only at 13.4 dBm while for macro there were settings such as 16.4dBm, 17.7 dBm..
How can we check if 13.4 dBm (or 17.7 dBm) is the maximum in the parameter dump?

[sak2e]

As I Know it's limited by Radio module, depend on your vendor and type of RF module.

[marcengo]

Hi, ulhwbest.

There is a series of factors which affect the RS power (a.k.a Power Spectral Density), but let`s start with the simplest case, which is even power distribution over all resource elements.

Assume you have 20W in your amplifier. You will distribute the 20W equally among all LTE subcarriers. Assume you have 10MHz spectrum, then you will be dividing the 20W with the 600 REs available for that BW. This math will give you the famous 15dBm RS.

Things get a little bit more complex when you start playing with pA and pB, this way you can allocate more or less traffic to RS and other channels of the grid. For that, you can check a couple links:
http://www.wirelessdesignmag.com/blog/2011/02/understanding-downlink-power-allocation-lte
http://lteuniversity.com/get_trained/expert_opinion1/b/nishithtripathi/archive/2015/05/29/reference-signal-power-boosting-in-lte.aspx
http://www.sharetechnote.com/html/Handbook_LTE_DownlinkPowerAllocation.html

[omarGSMUMTS]

in huawei it depends on RRU type.
for exapmle RRU3953 can support 40w in evry port. so it possible to set 18.2 . if you are using it in multi mode (2G) you have to calculate the remaining power(80 - trxnumber*powerin each trx) you get the acceptable power