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AMR coding mode determinating

Started by Unknown September 13, 2002
hi all,

I am wondering to know the procedure and which module that determinat
the AMR coding mode (different bit rate). Besides, please introduce
some reference articles for me about this to read.

Regards,
lee



Hi,

All I know comes from a bit of reading on AMR signalling in a mobile
phone. I hope this helps:

in-band control bits are sent

- DownLink ( Base Station to Mobile )

Mobile reveives the bitrate to use for decoding (-> CMI = Codec Mode
Indication ) alongside the speech bitstream. The CMI is chosen by the
Base Station depending on Uplink connection quality criteria. - UpLink ( Mobile to Base Station )

To encode user's speech, the mobile is also being given a bitrate mode
along the downstream ( -> CMC = Codec Mode Command ).

The mobile also polls downlink quality and sends the base station a
request for increasing or decreasing the bitrate for downstream ( -> CMR
= Codec Mode Request ). Then the BS decides whether to take it into
account or not.

If you want to read more go to http://www.etsi.org and have a search for
spec GSM 05.09 : Link adaptation.

have fun

Julien Villeret

Ѥ~ wrote:
>
> hi all,
>
> I am wondering to know the procedure and which module that determinat
> the AMR coding mode (different bit rate). Besides, please introduce
> some reference articles for me about this to read.
>
> Regards,
> lee > _____________________________________
> Note: If you do a simple "reply" with your email client, only the author of
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your answer to be distributed to the entire group.
>
> _____________________________________
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>
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>
> To Post:
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>
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VCard
Julien VILLERET <>


Work: +33 (0)2 99 86 97 13

Hi,

My Question is regarding the AMR Mode adaptation on the IPNetwork. That is
when AMR is wroking with RTP. Is there any kind of Recommendation on this(
like GSM 05.90 for Cellular transmission). Any kind help is most welcomed.

Regards

Shehzad Hanif ----- Original Message -----
From: "Julien VILLERET" <>
To: <>
Sent: Friday, September 13, 2002 6:37 PM
Subject: Re: [speechcoding] AMR coding mode determinating > Hi,
>
> All I know comes from a bit of reading on AMR signalling in a mobile
> phone. I hope this helps:
>
> in-band control bits are sent
>
> - DownLink ( Base Station to Mobile )
>
> Mobile reveives the bitrate to use for decoding (-> CMI = Codec Mode
> Indication ) alongside the speech bitstream. The CMI is chosen by the
> Base Station depending on Uplink connection quality criteria. > - UpLink ( Mobile to Base Station )
>
> To encode user's speech, the mobile is also being given a bitrate mode
> along the downstream ( -> CMC = Codec Mode Command ).
>
> The mobile also polls downlink quality and sends the base station a
> request for increasing or decreasing the bitrate for downstream ( -> CMR
> = Codec Mode Request ). Then the BS decides whether to take it into
> account or not.
>
> If you want to read more go to http://www.etsi.org and have a search for
> spec GSM 05.09 : Link adaptation.
>
> have fun
>
> Julien Villeret
>
> Ѥ~ wrote:
> >
> > hi all,
> >
> > I am wondering to know the procedure and which module that determinat
> > the AMR coding mode (different bit rate). Besides, please introduce
> > some reference articles for me about this to read.
> >
> > Regards,
> > lee
> >
> >
> > _____________________________________
> > Note: If you do a simple "reply" with your email client, only the author
of this message will receive your answer. You need to do a "reply all" if
you want your answer to be distributed to the entire group.
> >
> > _____________________________________
> > About this discussion group:
> >
> > To Join:
> >
> > To Post:
> >
> > To Leave:
> >
> > Archives: http://www.yahoogroups.com/group/speechcoding
> >
> > Other DSP-Related Groups: http://www.dsprelated.com
> >
> >
> > ">http://docs.yahoo.com/info/terms/
>
> _____________________________________
> Note: If you do a simple "reply" with your email client, only the author
of this message will receive your answer. You need to do a "reply all" if
you want your answer to be distributed to the entire group.
>
> _____________________________________
> About this discussion group:
>
> To Join:
>
> To Post:
>
> To Leave:
>
> Archives: http://www.yahoogroups.com/group/speechcoding
>
> Other DSP-Related Groups: http://www.dsprelated.com > ">http://docs.yahoo.com/info/terms/