Cell breathing in LTE?

[s.sunilpal123]

Hello friends,

When we increase loading in an LTE system, the cell radius for a given cell edge rate reduces.

Considering in an LTE system, a UE already uses the lowest possible MCS, & the loading increases at this moment; the cell radius for the rate reduces.

SO does this mean LTE too suffers from cell breathing effect?

[firstmaxim]

Hello friends,

When we increase loading in an LTE system, the cell radius for a given cell edge rate reduces.

Considering in an LTE system, a UE already uses the lowest possible MCS, & the loading increases at this moment; the cell radius for the rate reduces.

SO does this mean LTE too suffers from cell breathing effect?

No cell breathing in LTE because there is no or minimum intracell interference in LTE, unlike in WCDMA cells where all users are assigned the same frequency resource.

[s.sunilpal123]

But won't a user at cell edge be refused service (assuming he is already getting the lowest possible edge rate) when another user (near the enodeB) loads the network?

[firstmaxim]

But won't a user at cell edge be refused service (assuming he is already getting the lowest possible edge rate) when another user (near the enodeB) loads the network?

Unlike in WCDMA, the resource blocks given to the UE close to and farther away from eNB are different. Admission control, will ensure that the closer UE does not hog the entire bandwidth.

[s52d]

Unlike in WCDMA, the resource blocks given to the UE close to and farther away from eNB are different. Admission control, will ensure that the closer UE does not hog the entire bandwidth.

Hi!

As several cells hare same bandwith, cell breathing is here to stay with us.
On fully loaded systems (Of course I belive over 100 Mbit/sec/cell in 20 MHz bandwith)
it is unavoidable. Good plain C/I ...
I even saw cell breathing in GSM. Uplink interference.

Today, it is not an issue in empty networks - and I am not confident in X2 coordination
given todays state of LTE software.
Even in plain old R99 UTRAN this was non issue untill we put HSPA on top of voice.

Disclaimer: no LTE network around, no hands on experience here.
Can someone with real network comment?

BR
s52d

[MINTO]

Go through sceduling also when relating data resource allocation

[edinburgh]

(in wcdma) Taking into account interference due to cell load...more users..more cell loading..more interference..changing that cause cell breathing...

In LTE, no. of PRB per user, MCS, channel usage per TTI, SNR govern the cell range...

Anyway, according to 3GPP, LTE cell range can go up to 15 Km.

With modified parameter, we even tested 73Km LOS and working perfect.:p

[Mctest]

Am I right that cell breathing it is result of AC algorithm,because more users more DL power usage then more UL interference and it will lead to the lots of blockings.

[firstmaxim]

Hi!

As several cells hare same bandwith, cell breathing is here to stay with us.
On fully loaded systems (Of course I belive over 100 Mbit/sec/cell in 20 MHz bandwith)
it is unavoidable. Good plain C/I ...
I even saw cell breathing in GSM. Uplink interference.

Today, it is not an issue in empty networks - and I am not confident in X2 coordination
given todays state of LTE software.
Even in plain old R99 UTRAN this was non issue untill we put HSPA on top of voice.

Disclaimer: no LTE network around, no hands on experience here.
Can someone with real network comment?

BR
s52d

Agree that other cell interference could result in LTE cell breathing. Hence, Geometry factor (other to same cell interference) should be accounted in the link budget. THis in turn turn will impact the MAPL.

[mati]

Hi, Guys.
I will renew this topic. I'm just planning LTE network for my diploma.
So, I saw that when we grow resource block for uplink, the acceptable suppression is also grow. Therefore, calculating the maximum range for uplink is down.
I would like to note, that the cell radius depends on the number of resource blocks.

I know that cell breathing refers the C/I in cell. But if we also could talk about cell breathing in LTE or some other translation in this occurrence?