what are the main causes of bad speech quality inde(sqi) in gsm network

By tmassamba ·
i want to know how to improve speech quality in a gsm network

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What would you think the answer would be?

by robo_dev In reply to what are the main causes ...

What sort of issues might exist on a network covering a wide geographical area?

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Connection speed, voice codecs and policy

by TobiF In reply to what are the main causes ...

If a network suffers from low signal levels and interference (which result of a poorly planned network, lack of frequency spectrum, radio path attenuation or the operator trying to stretch the distance between base stations) then more of the data channel will be used for error correction codes, and less data speed can be used to carry speech data.

From time to time, new, improved codecs become available, but can, of course, only be used if both the network and the handset support this particular encoding.

Many operators try to get more capacity from the network by employing half-rate codecs (this will, of course, give less speech quality, as well.)

Full rate uses 2 out of 16 timeslots in a 200 Khz channel. Half rate uses 1 timeslot.

A week ago, I saw that some operators in UK are experimenting with HD codecs, with even higher data rates.

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by robo_dev In reply to Connection speed, voice c ...

How will these students learn if you do your homework for them?

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by TobiF In reply to Shhh.....

1. I wanted to show how much I know :) (And I'm not sure that you'd easily find all these directions easily via Google.)
2. I had spare time, it's weekend here
3. I'm sure that even his teacher won't put the whole picture on the desk. If this is from a physics or math class, then they'd totally miss the commercial aspect of it. Still, I tried to most point out directions. If the guy just repeats this, without understanding, then he's an easy target for follow-up questions, which certainly will follow. :)

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