- This topic has 10 replies, 1 voice, and was last updated 9 years ago by
prof.
-
AuthorPosts
-
prof
Guest1. When we say that power control is disabled on BCCH TRX. Does it mean all 8 time slots of BCCH TRX or only 0th time slot?
2. Suppose time slot 6 of BCCH TRX is defined to be TCH. What if this time slot is idle? Will the BTS transmit some dummy data or will it remain silent?
3. Do we have power control enabled in the uplink on BCCH TRX time slots?
pix
Guesthi prof,
1/ it means that the DOWNLINK PC is disabled on ALL the 8 timeslots of the BCCH TRX. The principle is that the BCCH frequency in DL should always be emitted at max power.
2/ it will transmit dummy data at max power (btw, DL DTX is disabled on BCCH TRX as well, for the same reason)
3/ yes, UL PC works the same on all TRX.
Cheers,
pixBT
Guest@pix
2/ The BTS will remain silent in idle mode because there is no communication with the mobile device.
prof
GuestThanks pix and BT.
I see a little debate on my 2nd question. Can there be an agreement?pix
Guestprof,
indeed there is a disagreement… but i hope you know who to trust 😉 i would always tell if i’m not sure about something…… but here, i know *for sure* the BTS transmits dummy blocks on the BCCH carrier in downlink when there are no actual calls. that’s one of the reason why the bcch frequency needs a “cleaner” frequency planning. And that’s also a reason why BCCH frequency is the one which is NOT hopping in SFH hopping mode.
regards
pixBT
Guest@pix
And how is possible that tracing my phone in idle mode I do not see any dummy data?
What are you using to trace this dummy data?
pix
GuestBT,
well, you are actually seeing it : it’s thanks to this “dummy signal” that your ms is able to measure the dl_rxlev(serving) in idle mode, and to measure the dl_rxlev(n) in dedicated mode.
it might not be “dummy blocks” at layer 3, but perhaps just a pure sinus signal. I don’t know those details.
regards
paraHO
GuestI agree with you Pix
GSM 0502
pix
Guestgive me five !
BT
GuestYes 🙂
prof
Guestthanks you pix/all.
-
AuthorPosts