Any further findings?
If the whole area is affected, go for the feature activation or changing frame type.
If only 1 or few sectors (covering same area) is affected, make site health check (jumpers, feeders, connectors, alarms, vswr, external source of interference.
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Thanks!
Impacted whole costal area.
How is the weather there?
Is the problem occuring tje se period every year?
Or every season?
What is the affected band?
Band is 2300.
It’s mainly due to storm in now a days storm is very frequent.
Any other suggestions which will reduce this ducting effect (it is “atmospheric ducting” phenomenon).
Will try to implement @krunal_shah suggested parameters asap and share the outcomes to all.
Hi, Sir.
I’m not a huge TDD expert, but besides what was already said, make sure Downlink interference shaping is enabled, maybe playing with Configurable Uplink Interference Regions may also help.
In addition to that, try DL deboosting, starting UL PWR control at a lower p0 for both PUSCH and PUCCH, maybe also playing with other parameters related to it.
Maybe slowing down RACH as well.
Thanks @marcengo.
Will check this part as well and do the trial with small cluster.
If anyone knows exact parameter name, please share. (Nokia system)
It seem shat 3GPP seriously considers issue with this phenomena in 5G networks (especially TDD) and in rel16 we will have: Remote Interference Management (RIM) and Cross-Link Interference (CLI) Management: Introduces techniques for managing interference from distant cells in Time Division Duplex (TDD) networks in the presence of tropospheric scattering, as well as managing inter-operator interference.
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Mostly there is no sure shot way to mitigate TDD interference but what you can do is try to findout which ENBs are acting as aggressors. We have developed a few tools inhouse to find out agressor with the maximum number of victims causing TDD interference. Once you identify your consistent aggressors than you can apply various mitigation techniques. But mostly as the TDD interference is subjected to weather/tropospheric duct and many other things. More often than not we find only a little relief
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Anyone having new idea or mitigation plan?
All Vendor developed the ducting mitigation feature to convert SSF7 to SSF5 during the ducting. Best solution is " Based on trace server report we need to do the Physical optimization of TDD site aggressor sector " .
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not sure on Nokia There has feature available or not, in ZTE we can shift SRS to last symbol with enabling Feature “TDD Atmosphere Ducting”, it will be help full for reducing ducting impact
Its available in Ericson , Nokia , ZTE and Huawei…
Hi.
For those who have tried Ducting TDD feature:
How much was the gain achieved regarding UL RSSI issue?
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It’s about ducting intensity.
Usually about 15% after ssf7 to ssf5 change.
Sometimes > 24 hours ducting continuous.
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Yes it is useful in ducting scenario but difficult to prove benefit in terms of RSSI
Hi LTE experts: Do duct Interference create issue for TDD only in 4G?
Yes, its impact is in TDD only - major dent on RSSI due to this its impact on traffic dip.
Gain is at the cost of DL T’put degradation.
I am saying that you can control accessibility part very well by changing SS5 instead of SS7 due to increase of Guard period in frame. But it will impact DL T’put with reduced number of DL Time slots in frame.
It depends on customer which things to tolerate in ducting scenario.
In my view, accessibility is more important than T’put in such cases.
At least end user can get small message with lower T’put.
Golden advise on ducting: Ducting scenario generally observed in morning & evening hours only (Typical time 5 to 8 AM & 7 to 9 PM) at time of temperature transition in atmosphere. You can very well isolate it with morning busy hour (typically 10 to 12 noon in mobile network).
If i understood, the interference exist also on LTE FDD in case of passive intermodulation e.g PIM?