UL interference in LTE

[jbada]

Hi Forum

Could you please recommend me some value for UL interference in LTE (Noise and Interference Power on PUSCH)?

As far I know cells with uplink interference are those whose RSSI values are high (higher than -90dBm)

Thank you for your comments

[DANORM]

Antenna port RSSI= -120+10*log(RB number)


Band(MHz) RSSI(dBm)
1.4 -111
3 -107
5 -105
10 -102
15 -100
20 -99

[jbada]

Many thanks DANCESTORM for your clarification.

Any recommendation for lowers values like -120dBm.

Thanks

[wolverine]

Antenna port RSSI= -120+10*log(RB number)


Band(MHz) RSSI(dBm)
1.4 -111
3 -107
5 -105
10 -102
15 -100
20 -99

Hi Dancestorm, interesting. What is the source of this?

[Muhammad]

Hi Dancestorm, interesting. What is the source of this?

Actually the RSSI should be calculated as

Noise floor (RSSI) = -174 + Noise Figure (Equipment specific) + 10 log (Bandwidth)

In LTE a RB consists of 180kHz so 10 log (180,000) = 52.5 dB

The background noise for one RB = -174 + 52.5 = -121 dBm

Assuming a generic Noise Figure of 3dB, and a bandwidth of 1.4 MHz (6 RB) the RSSI would come

-121 + 3 + 10 log (6) = -118 + 7.7 = -110 ~ -111 dBm


Similarly You can calculate the RSSI value for any given Bandwidth.


Please add reputation if you find this answer as helpful in your query.

[rosan]

Is there any modification required for this formula when applied to TDD?

rosan

[Muhammad]

Is there any modification required for this formula when applied to TDD?

rosan

This formula works on the background Noise and bandwidth of signal only.

BR
Jamil