No subject


Sat Apr 16 12:26:00 UTC 2016


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




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