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gogotchiya83
2009-11-22, 06:37 PM
I am working on a model tuning (propagation model) of a network already on Air.
Given the constraints of lack of equipment I use a scanner PCTEL with external antenna in the measurement chain.
So we proceeded to lock the scanner on a specific frequency (BCCH of the cell taken as a witness to calibrate a type of clutter), the scanner has taken action in a periodic manner with a good interval between two successive measurements (100 ms). Yet the same BCCH is used by other cells, then the scanner decodes BSIC of other cells once we went a little far from the cell object of study, so we cannot take measurements of Rxlev below -80 dbm (Cell object of study is inside the coverage and it’s surrounded by other cells using the same BCCH (constraint of the frequency plan)).

My question is as follows:
• Can we have good calibration results by using only values below - 80 dBm?
• Have you ever used a scanner during calibration in a network on air (do you have any documents describing the procedure)?
• After filtering from the prior test (BSIC / BCCH of the cell object of study), I have concluded approximately 4000 measurements (02 hours of Drive test with 40 km/h speed of the vehicle)) is it enough for a good calibration?

Thank you for your support.

justdream
2009-11-24, 05:36 AM
My question is as follows:
• Can we have good calibration results by using only values below - 80 dBm?
no, and why you have a lot of Co. BCCH near to each other (it's so strange !!!!)

• Have you ever used a scanner during calibration in a network on air (do you have any documents describing the procedure)? I will check

• After filtering from the prior test (BSIC / BCCH of the cell object of study), I have concluded approximately 4000 measurements (02 hours of Drive test with 40 km/h speed of the vehicle)) is it enough for a good calibration?

no, but you can overcoem it by making a other drive tests in other areas belonging to the same clutter properties

gogotchiya83
2009-11-24, 03:12 PM
Dear expert,

The same BCCH is used withe different BSIC at the same cluster due to the insufficient number of frequencies of the operator (5 Mhz = 26 frequency =18 BCCH + 8 MAlist for 150 sites at the same city with 800 m as a distance between sites!!!).

Can you suggest us a method to do the calibration in this complicate situation ?