- This topic has 9 replies, 1 voice, and was last updated 7 years, 6 months ago by pix.
14th November 2007 at 05:08 #49677mehrdadGuest
Hi everey body,
You know MS for implementation inter-cell handover will send handover access to new cell.I want to know HO access format. for example rach is 1 octet. could you please tell me?14th November 2007 at 07:23 #49678pixGuest
you can have a look to 3gpp.org.
i can have a look later, but i’m afraid i’m going to forget 🙂14th November 2007 at 09:20 #49679mehrdadGuest
i am searching 3gpp site but i couldn’t find HO burst format until now. if you find it please tell me.
thanks alot18th November 2007 at 09:59 #49680mehrdadGuest
I found the “Handover Access” format finally. it contains 1 octet usefull data like “Rach” message. both of them will be sent on “Access Burst” so sometimes BTS detects “Handover Access” Burst as “Rach” wrongly and BSC assigns SDCCH to this request (SDCCH GHOST) that waste the SDCCH resource.18th November 2007 at 11:28 #49681pixGuest
good job 🙂1st August 2012 at 07:06 #49682splashingbeeGuest
I shall share what I found on HANDOVER ACCESS. HO Access Burst is basically a burst of bits – the 41 sync bits. There is a long guard period followed by 8 tail bits. This is followed by 26 encrypted data bits followed by 4 tail bits. Bits 88 – 156 are long guard bit period – to avoid any collision with other such access bursts.
The access burst is sent in 4 consecutive time slots if the systems are TDMA synchronized. Else the MS keeps on sending this burst unless the BSS replies with a PHYSICAL INFORMATION message containing the TIMING ADV information or Timer T3124 expires (HANDOVER FAILED).
Reference – Gsm – Architecture, Protocols and Services – Jörg Eberspächer, Hans-Joerg Vögel, Christian Bettstetter, Christian Hartmann | Page 152
Sorry to dig out this thread after so long. However the info may be useful to somebody else.1st August 2012 at 13:27 #49683pixGuest
thanks dude 🙂1st August 2012 at 23:52 #49684DellGuest
what’s the cause of Handover failure-unspecified? Radio? MSC?
Dell11th November 2013 at 04:32 #49685kalpeshGuest
How many Handover Access burst MS may send over SACCH?12th November 2013 at 11:31 #49686pixGuest
HO ACCESS is rarely sent on SACCH. If cell is synchronized (intra-BTS HO), then HO ACCESS is sent on FACCH exclusively, 4 times.
In case on non-sycn cells :
184.108.40.206.2 Non synchronized cell case
After having switched to the assigned channels, the mobile station starts repeating the HANDOVER ACCESS message in successive layer 1 frames on the main DCCH ( = FACCH) and optionally on the SACCH. This message is sent in an access burst. Its content is reduced to the handover reference information element. The mobile station starts timer T3124 at the start point of the timeslot in which the HANDOVER ACCESS message is sent the first time on the main DCCH.