How to reduce Uplink Interference in LTE apart from UL eICIC?

Hi All.

How to reduce Uplink Interference in LTE?

It is very tricky as UL footprint is very much different compared to DL footprint.

Apart from UL eICIC, any other feature that would help to reduce UL Interference?

First you need to check your HW in sector after external interference.

I am saying interference, mostly is not external interference it is traffic interference between cells.

Uplink Comp may be useful.

What is UL eICIC?

Uplink InterCell Interference Coordination.

It is Huawei feature.

Is it for uplink interference cancellation?

Yes, very nice one.

I think in Downlink we have one too.

Yes, there is for DL as well.

Reduce p0nominalpusch to lower value.

P0 is a design/optimization parameter that balances a trade-off between maximum UE uplink throughput and overall cell capacity. With a high P0, a close-in UE with very low RF path loss can achieve very high throughputs per RB because it achieves very high SINR (signal to interference plus noise) levels per RB. Similary UE’s who can achieve P0 target will transmit at higher power spectral density (PSD, or power per RB). However the trade-off is this higher PSD creates more co-channel interference for adjacent cells, with the overall result of lower overall system maximum UL (UpLink) capacity. Vice-versa, with low P0 setting, the maximum UE throughput in very low RF path loss conditions is not nearly as high because it is more noise limited (does not achieve as high SINR per RB); however the advantage here is much less co-channel interference to adjacent cells. P0 has no impact on UE’s at cell edge because they are at minimum # of RB’s and maximum power anyway (i.e. they are just ‘hanging on for dear life’) , at least for Macro cells.

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Yes, tunning of power control parameter P0 nominal pusch and P0 nominal pucch helps in interference reduction.

Not sure it really helps:
If I make it high I will reduce cell range.
If I make it low packets will not go through in uplink.

I think it has more to do with footprint of cells, dominance and best server.
Also it has a lot to do with UE distrbution.
How they are spread among cells.
Over the cell footprint how UEs are spread.

Issue also comes from overshooting cells: cells that have over 80-90 neighbors and operator do not want to tilt due to dominnace for 50-60m in some remote area

No change in cell range if we increase pzeronominalpusch.
It will just transmit with an increased power close to cell.

How about UEs at cell edge that cannot make it to such a high power?

It’s accessing issue, nothing to do with cell range.

It is tried and tested parameter over all nw topologies.
Try once.
If you make it low, not much impact on kpis.
Just ensure that don’t reduce more than 5 dBs of current value.

No impact on Cell Range.
CellRange is affected by the PRACH/RSI configuration.

Isn’t just for Access?

Once you get access I think is very much affected by pzeronominalpusch because eNodeB expects that level of power in Uplink.

Yes, but how do you correlate it with CellRange?

Because p0NomPusch is used for calculation in UL P1.