UEs being bumped from B20 to B3 on Three. Paging editorsean

ED E

Anyone else doing testing noticed Three eNodes bumping a UE on Band20 over to Band3 after a few seconds? I've been trying to force my handset over to 20 to test 10 + 10 config. It works for a second until the cell gives me the boot

As this is very much a master slave relationship I'm not sure theres anything I can do but suggestions welcome.
Ta,
ED-E.

editorsean

I don't have my phone rooted, so have not tried forcing my phone to use a specific LTE band.

It's possible the Three masts running dual carrier LTE use the round trip delay to determine which band the device may use (Distance Based Inter-frequency Handover), a feature supported by some Huawei eNodeBs (source):



I remember the odd thread where people using an upper band (1.7-2.7GHz) Yagi or patch antenna could no longer pick up Three after the mast got upgraded. This is likely the result of the cell tower eNodeB trying to force the user's device to use band 20, where 800MHz is well below what the antenna can pick up. This would also explain why some people complained about losing 4G coverage altogether after a mast upgrade as their handset probably does not support band 20 that the mast is trying to hand the device over to.

In this situation the reverse may be happening where the eNodeB determines that your device is very near and in turn trying to hand it over to band 3. This would make sense, by restricting nearby devices to band 3, this effectively frees up bandwidth on band 20 for the further away devices.

ED E

From the macro perspective that makes sense but a bit annoying for testing. In South Dublin its hard to significantly out of range of Band3 cells. Gonna have to run to da hills to try and trigger it.