What's the worst RTWP value from interference source?

RAN
, ,
4

Cause may be VSWR or Load on network.
Or may be TX RX port swap will cause.
Mostly in case of VSWR RTWP will be below -75.

5

Thanks. So at -94 to -96 am not gonna pick up anything on spectrum analyzer. Got it. :wink:

6

Below -75 or higher -75?
-70 is higher than -75
Kind of tricky. :slight_smile:

1 Like
7

Yes, that I know.
I was asking the affected RTWP values in terms of hunting, at what values does it have impact on the network at what is the most affected value I can pick it up when hunting?

8

Above -95 is always good also check RSSI value.

9

Hi,

I wrote a tutorial about RTWP one decade ago. :wink:

Maybe you’re gonna like it.

2 Likes
10

I just found on the field interference values higher than -80 dBm.

11

The worst has been found almost -60 dbm in our NW

12

FFT Scan can be done from the back office and FMA can be used for analysis showing PIM Interference, Wideband External Interference, and Narrowband External Interference. But U can get a low as -60dbm which would probably be due to poor installation on site.

1 Like
13

Last night we switched all the sites in town at night and run OSS and we were still picking up some RTWP.
Could it mean it’s indeed external cause after all sites were off and runned OSS we were still picking up something?

14

What value?
Are there any repeater /small cell near site?

15

Not repeaters, but some some small cells seems to be there.
But with spectrum analyzer when hunting we are not picking up anything.

16

It can be external!
Have you verified any GPS clock alarms on neighbor or nearby sites?

1 Like
17

Have you find increase in UL BLER as well without increase in user?
Is it TDD site?
Also look if ducting is there or not.

Some links may be useful:

1 Like
18

All the sites are FDD.

I have hunted almost all the areas affecting cells for external interference without any luck of picking up a thing. :frowning:

What should be the next step? And what can you all dears recommend in terms of further investigations?

1 Like
19

Have you checked PIM?

20

PIM was never done yet. :frowning:
Also, on the other site they changed all the cables, antennas but still they RTWP is high.

21

For external interference, if possible, visit on highly impacted site location and use Spectrum Analyzer and connect with your Antenna.
Did you identify the suspected Direction?

1 Like
22

Better with espectrogram.
If you have high RTWP your issue is external interference.

I have this problem with chinese repeater, check this picture.

image
image1236×315 87 KB

1 Like
23

Is it good practice to go up to site location (assuming rooftop), leaving the sector behind you and moving spectrum antenna around?