Handle invalid LTE RSSI?

[handymenny]

Some devices (especially Samsung devices) may report an LTE RSSI equal or very similar to RSRP, which cannot be a valid value.
Some apps in these cases don't report the RSSI value at all or allow the user to replace it with a calculated value.

The first question is how to figure out that RSSI is invalid.
I would consider RSSI invalid if RSSP >= RSSI (strict check) or if RSRP - RSSI > RSRQ_MAX (relaxed check)

Then for how to calculate it, if that is the path you want to follow for this library, this formula can be used:
RSSI = 10 * log(N) + RSRP - RSRQ
Where N is the number of resource blocks. N can be derived directly from the bandwidth, common values are 6, 50 (10MHz), 75 (15MHz), 100 (20MHz). 6 could be used for neighbour cells in some cases, but shouldn't be used for serving cells.

And now comes another question, what if BW isn't available?
An average value could be used, e.g. 75. Or an average value according to frequency, e.g. 50 for low bands, 75 for mid bands, 100 for high bands.

Should this kind of post-processing be in netmonster core?

[qquiderr]

on tmobile czech show 20MHz on band 800 or 700, in O2 czech sometimes show BW 15 on 700 or 800.

[qquiderr]

Wrong BW on tmobile:
https://ibb.co/zZHjtR1
https://ibb.co/KW4BdHd

and some BW is missing
https://ibb.co/Y773gG8
its 3CC, but shows 20+15 (2100+1800) and missing + 10 for 700.

[mroczis]

1. RSSI, RSRP issue
   Rules you mentioned do work in theory. Unfortunately values provided by each device may vary. Meaning that some devices do report false-positive RSSI, RSRP, RSRQ values. If you need to be sure about data validity then I'd advise looking for some professional device that guarantees validity of measurements (= not an Android device). I was already playing with formula you mention but it did fit only in 10 percent of all measurement (assuming I know RSSI, RSRP, RSRQ and bandwidth).

2. Bandwidth issue
   NetMonster (Core) consumes public data from the device and such data are updated asynchronously (by the system). Meaning that at one point device can update cell information and after some period of time bandwidth info. NetMonster "glues" them together and shows. All data are real-time. There's no guarantee that provided data are 100 % correct.

Generally - if you need reliability, you need to find another device that does not mess up with data. Generally devices with Exynos (and Google Tensor) processors do perform worse compared to Qualcomm.

[handymenny]

I see your point. it's just that in some cases end users prefer "guessed" data to completely invalid data.
if I wanted accurate data I wouldn't have opened this issue :)