Huawei LTE TA

[Realman]

Hello Huawei expert,
Kindly share formula to calculate distance using LTE TA KPIs.
BR

[eng.samehglal]

Time slots are shorter in LTE than in GSM. Correspondingly, the units of time used for specifying the Timing Advance are also smaller, namely 0.52 µseconds (16 * 1/(15000*2048) seconds) .
So a change of 1 in TA supposedly corresponds to a 156.14 meters in round-trip distance, or 78.07 meter one way (d = c * Ta / 2, where c = 299,792.458 m/sec, Ta = 16 * Ts, and Ts = 1/(15000*2048)).

Again, there is an upper limit on possible values. In LTE, the initial TA sent from the BS to the UE is an 11 bit quantity, restricted to a maximum value of 1282 (incremental updates sent from the BS to the UE are signed quantities packed into six bits). This provides for a maximum (one-way) distance of just over 100 km.

TA index.jpg

[kevin_h811]

Hi,

Is this applicable for LTE FDD and LTE TDD?

What if L2600,TDD is this same also ,I mean is this applicable also for the TA Index you shared?

Pls share your materials if you have.

br//

[sak2e]

Hi,

Is this applicable for LTE FDD and LTE TDD?

What if L2600,TDD is this same also ,I mean is this applicable also for the TA Index you shared?

Pls share your materials if you have.

br//

it seems both of TDD and FDD uses the same approachment,
i am just wondering why Huawei did not have cell size index parameter similar in Nokia in order to set TA range between index

[Realman]

Thank you my friend. This distance in your snapshot are use to calculate Max TA,for TA Midpoint,we use different distance value.I understand how to calculate distance using TA counters,my question is:
1. To determine overshooting neighbor cells,should I use TA Max distance or TA midpoint distance?
2.sometimes we use TA greater than 2km to determine overshooting cells,but this calculation might not give the actual overshooting cells because some cells have radius greater than 2km. I suggest using TA greater than cell radius to determine overshooting cell.
Please any expert should recommend how to calculate overshooting cells using distance from TA.

Thanks

[Realman]

Issue solved.
If TA of a site greater than intersite distance,overshooting problem occur.

[emmanuel obiora]

Check if the azimuth is facing the site you are considering to be inter site distanced with, else it could be open area.

Issue solved.
If TA of a site greater than intersite distance,overshooting problem occur.