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Number of symbols in a burst =3D 156.25 symbols, and burst time 156.25 x 3.69... =3D 576,92=ECs Number of symbols in TDMA frame is 8 x 156.25 =3D 1250 symbols, Number of symbols in Multiframe is 26 x 1250 symbols. On Fri, Jan 7, 2011 at 8:51 AM, Nataraju A B <natarajuab.tech at gmail.com> wr= ote: > > Hi Andreas, > Thanks for the speedy reply. > The link which sent you is=A0definitely=A0useful. But the very basic ques= tion I wanted to get a clarification was that, what is the drive behind sel= ection of burst time to be 577us. > For example the audio frequency can range upto 4Khz. The sampling frequen= cy should be 8Khz. If each sample is of 8 bit accuracy. This lead to 64K bi= ts of data. ...... =A0If we explore further on these lines we should be abl= e to correlate to the time 577us for each burst. > I wanted some more info these lines. What was/were the drives behind sele= ction of this burst time. Otherwise what are the other end requirements led= to selection of this burst time and in turn TDMA frame hierarchy. > Thanks, > Nataraju A B > On Fri, Jan 7, 2011 at 7:01 PM, Andreas.Eversberg <Andreas.Eversberg at vers= atel.de> wrote: >> >> in addition: >> >> Traffic Multiframe Structures - The 26 traffic multiframe structure is >> used to send information on the traffic channel. The 26 traffic >> multiframe structure is used to combine user data (traffic), slow >> control signaling (SACCH), and idle time period. The idle time period >> allows a mobile device to perform other necessary operations such as >> monitoring the radio signal strength level of a beacon channel from >> other cells. The time interval of a 26 frame traffic multiframe is 6 >> blocks of speech coder data (120 msec). >> (http://www.althos.com/tutorial/GSM-tutorial-frame-structure.html) >> >> one encoded speech block lasts 20ms. >> >> >> =A0 =A0 =A0 =A0576,92307692307692307692307692308us per slot >> =A0 =A0 =A0 =A04615,3846153846153846153846153846 per 8 slots (1 frame) >> =A0 =A0 =A0 =A0120ms per 26 frames (6 speech blocks) >> >> >> > > > > -- > Thanks, > Nataraju A B