- This topic has 13 replies, 1 voice, and was last updated 14 years, 2 months ago by goast.
17th September 2005 at 05:54 #42180joodGuest
What is the benefit of using COMMON BCCH in (900+1800) GSM…. Is it just for increasing capacity by 3Ts unequipped on 1800 system, or there is another benefit of this feature (reduce signaling load????).
Please articulate it, if possible.
th in advance.17th September 2005 at 08:02 #42181RajanGuest
The benefit is for the customer that he has buy lesser number of frequencies. Also the capacity of the area wrt TRX increases.
Signalling load is also one of the reasons.
Rajan17th September 2005 at 12:41 #42182BokoGuest
Also It is good for the reduced number of neighbours, all in one band (900)
Boko19th September 2005 at 04:49 #42183M.ThyagarajanGuest
but the offset for handover between layers(900/1800) has to be set carefully of this may leed to congestion on one layer while the other layer is under utilized19th September 2005 at 10:02 #42184BokoGuest
…Which is very useful if the congested layer is the inner one.
I think the most difficult thing is the handover margins from inner area to a neighbouring cell. You can easy go into a Ping Pong Handover. Cell_1 1800->neighbour cell_2->Cell_1 900->Cell_1 1800…..19th September 2005 at 16:45 #42185moreGuest
Because BCCH is one on sector, & as i know there is no HO without measurement on neighbourBCCH…..so from inner to outer how MS measure neighbour(for RXQU & RXLEV) .
thus maight there is no need for HO to move on whole cell( reduce signaling on SDCCH, also BCCH,SACCH & PCH)
is it right….
regards21st September 2005 at 04:41 #42186M.ThyagarajanGuest
there is always the intra handover.21st September 2005 at 06:58 #42187BokoGuest
You can go directly from the inner zone (1800) to whatever neighbouring cell (900/1800) – at least for Siemens. The reverse is not true – you always do HO from neighbour to outer zone (900) and immediately to inner (1800). Also for siemens there is no offset for inner complete (only the difference in Pmax – 3dB) and HO margin is one and the same for both zones (HOmargin effective is with 3dB difference). O-ooo I almost forgot no prevention of back HO due to reason “Better cell”.12th October 2005 at 20:26 #42188monemGuest
Regarding all this clarification:
1) is there any difference at intra HO performance between non syncronised 900/1800 & syncronised 900/1800.
2) In case of syncronised 900/1800, what the effect of implementing COMMON BCCH on intra HO.
3) the effect of syncronised 900/1800 on the radio network feature (FH, DTX, Allocating, assignment, cell reselection(idle mode),… etc
4) is there any SDCCH signaling on 1800 band in case of COMMON BCCH.
# sorry for my too much interrogation, but realy I need some one to clarify it, or provide me by some related DOCUMENT.
thanks13th October 2005 at 15:04 #42189BokoGuest
For siemens for sure there is a difference for intercell. Intracell what do you mean?
1) For colocated cells (synchronized) you can go for one inner zone of cell_1 directly to the inner zone of cell_2
4) No signaling or data chennels in the inner zone.
and neighbourcell list is reduced
rgds16th October 2005 at 12:03 #42190paryGuest
we use congestion relief HO on outer zone with distribution algorithm according to adjusted Idle TCH rate on outer, to move the call to inner.
to do HO inner>> outer the PBGT HO (LOL) must be controled with its offset.17th November 2005 at 12:57 #42191joodGuest
HI all again
Kindly I need out light on (power budget hand over algorithm).and how it implicates the rxlev & qulev. And how differ in performance from (minimum performance algorithm) which is used to give precedence to power control over handover.
Which is better….????
Thanks in advance.19th November 2005 at 15:21 #42192sankoosiGuest
# minimum performance algorithm: simple & (precedence for P Control over HO) BUT creates smeared cell boundaries when MS with high TX power goes distance byond its orignal border into another cell, so it produce high interference.
# Power budget algorithm: complicated algorithm (precedence for HO over power control),so it uses HO to maintain a certain level of Quality. so avoid the smeared cell and reduces co-channel interference.12th September 2006 at 07:39 #42193goastGuest
is it true, the main need for COMMON-BCCH is the increasing of trunking-gain.