Quantization confusion in pulse code modulation.

[shivajikobardan]

I have a question-:

This is a quantized version of an information signal. Here number of bits used to encode is 4 so there are 16 levels.

Here is the encoding.

I tried to do this with similar type of questions.

But as you see here is the problem. There are 5 Voltage levels but only 4 possible encodings. There is a solution to this afaik it is to let like-:


4V-2V=00

2V-0V=01

0V-–2V=10

-2V- -4V=11.

But that is making less sense to me at the moment.

Can you shed some light in this issue?

 

[Harald Kapp]

But that is making less sense to me at the moment.

Why? Where's the problem?
Look at this statement from your first picture:

 

[shivajikobardan]

thanks.