On Nov 5, 1:04 am, "BCLIM" <boonchun_... at (no spam) yahoo.com> wrote:
Hi,
I have a doubt on jitter generation. Wonder is the method to generate
jitter signal is that same as dithering generation method? Understand that
both are usign random signal generation with different distribution. For
example, triangular, rectangular etc.

I always thought that for a signal defined over a finite length of
time,
jittering added a randomness to the amplitude whereas dithering
added a randomness to the starting time.

Hope this helps.

On Nov 5, 1:04 am, "BCLIM"<boonchun_... at (no spam) yahoo.com> wrote:
Hi,
I have a doubt on jitter generation. Wonder is the method to generate
jitter signal is that same as dithering generation method? Understand that
both are usign random signal generation with different distribution. For
example, triangular, rectangular etc.

I always thought that for a signal defined over a finite length of
time,
jittering added a randomness to the amplitude whereas dithering
added a randomness to the starting time.

Hope this helps.

Greg

On 11/7/2009 12:56 PM, Greg Heath wrote:

On Nov 5, 1:04 am, "BCLIM"<boonchun_... at (no spam) yahoo.com>  wrote:
Hi,
    I have a doubt on jitter generation. Wonder is the method to generate
jitter signal is that same as dithering generation method? Understand that
both are usign random signal generation with different distribution. For
example, triangular, rectangular etc.

I always thought that for a signal defined over a finite length of
time,
jittering added a randomness to the amplitude whereas dithering
added a randomness to the starting time.

Hope this helps.

Greg

I think it'd help for the OP to clarify what he means by his
terminology.   In my experience jitter usually means random fluctuation
in period, (usually sampling period), while dithering usually means
adding small random values to an input to reduce quantization noise.

It's also not clear whether the OP is asking about unintentional or
intentional jitter.   Some clocking systems add jitter in order to
reduce spurious emissions related to the clock frequency.   Is that the
topic of the question?

--
Eric Jacobsen
Minister of Algorithms
Abineau Communicationshttp://www.abineau.com

On Nov 7, 6:02 pm, Eric Jacobsen<eric.jacob... at (no spam) ieee.org> wrote:
On 11/7/2009 12:56 PM, Greg Heath wrote:

On Nov 5, 1:04 am, "BCLIM"<boonchun_... at (no spam) yahoo.com> wrote:
Hi,
I have a doubt on jitter generation. Wonder is the method to generate
jitter signal is that same as dithering generation method? Understand that
both are usign random signal generation with different distribution. For
example, triangular, rectangular etc.
I always thought that for a signal defined over a finite length of
time,
jittering added a randomness to the amplitude whereas dithering
added a randomness to the starting time.
Hope this helps.
Greg
I think it'd help for the OP to clarify what he means by his
terminology. In my experience jitter usually means random fluctuation
in period, (usually sampling period), while dithering usually means
adding small random values to an input to reduce quantization noise.

It's also not clear whether the OP is asking about unintentional or
intentional jitter. Some clocking systems add jitter in order to
reduce spurious emissions related to the clock frequency. Is that the
topic of the question?

--
Eric Jacobsen
Minister of Algorithms
Abineau Communicationshttp://www.abineau.com

My understanding is that dithering doesn't reduce quantization noise
(power) in general, but de-correlates it.

[...]
Yes, and the decorrelation allows an increase of SNR with appropriate
filtering,

Eric Jacobsen<eric.jacobsen at (no spam) ieee.org> writes:
[...]
Yes, and the decorrelation allows an increase of SNR with appropriate
filtering,

What filtering is that? If oversampling is involved, there can be
filtering.

And perhaps there may be a "preference" in frequencies (e.g.,
the emphasis of the human ear in frequencies near 4 kHz), which would
permit some type of filter. But in general, there is no filtering that
can be done and dither actually increases the total quantization-related
noise power. That's not to say dithering isn't worth doing, however,
bacause the decorrelating is a distinct advantage.

[...]
This place is going to get really tiresome if every response to a
question has to include every possible nuance in the answer.

On 11/7/2009 12:56 PM, Greg Heath wrote:
On Nov 5, 1:04 am, "BCLIM"<boonchun_... at (no spam) yahoo.com> wrote:
Hi,
I have a doubt on jitter generation. Wonder is the method to
generate
jitter signal is that same as dithering generation method? Understand
that
both are usign random signal generation with different distribution.
For
example, triangular, rectangular etc.

I always thought that for a signal defined over a finite length of
time,
jittering added a randomness to the amplitude whereas dithering
added a randomness to the starting time.

Hope this helps.

Greg

I think it'd help for the OP to clarify what he means by his
terminology. In my experience jitter usually means random fluctuation
in period, (usually sampling period), while dithering usually means
adding small random values to an input to reduce quantization noise.

It's also not clear whether the OP is asking about unintentional or
intentional jitter. Some clocking systems add jitter in order to
reduce spurious emissions related to the clock frequency. Is that the
topic of the question?

--
Eric Jacobsen
Minister of Algorithms
Abineau Communications
http://www.abineau.com

Eric Jacobsen <eric.jacobsen at (no spam) ieee.org> writes:
[...]
Yes, and the decorrelation allows an increase of SNR with appropriate
filtering,

What filtering is that? If oversampling is involved, there can be
filtering. And perhaps there may be a "preference" in frequencies (e.g.,
the emphasis of the human ear in frequencies near 4 kHz), which would
permit some type of filter. But in general, there is no filtering that
can be done and dither actually increases the total quantization-related
noise power. That's not to say dithering isn't worth doing, however,
because the decorrelating is a distinct advantage.

On 11/8/2009 9:07 AM, wazerface at (no spam) gmail.com wrote:
On Nov 7, 6:02 pm, Eric Jacobsen<eric.jacob... at (no spam) ieee.org> wrote:
On 11/7/2009 12:56 PM, Greg Heath wrote:

On Nov 5, 1:04 am, "BCLIM"<boonchun_... at (no spam) yahoo.com> wrote:
Hi,
I have a doubt on jitter generation. Wonder is the method to
generate
jitter signal is that same as dithering generation method?
Understand that
both are usign random signal generation with different
distribution. For
example, triangular, rectangular etc.
I always thought that for a signal defined over a finite length of
time,
jittering added a randomness to the amplitude whereas dithering
added a randomness to the starting time.
Hope this helps.
Greg
I think it'd help for the OP to clarify what he means by his
terminology. In my experience jitter usually means random fluctuation
in period, (usually sampling period), while dithering usually means
adding small random values to an input to reduce quantization noise.

It's also not clear whether the OP is asking about unintentional or
intentional jitter. Some clocking systems add jitter in order to
reduce spurious emissions related to the clock frequency. Is that the
topic of the question?

--
Eric Jacobsen
Minister of Algorithms
Abineau Communicationshttp://www.abineau.com

My understanding is that dithering doesn't reduce quantization noise
(power) in general, but de-correlates it.

Yes, and the decorrelation allows an increase of SNR with appropriate
filtering, so it can be used to effectively reduce quantization noise.
But you're right, dithering by itself doesn't reduce quantization noise.

On 11/8/2009 5:53 PM, Randy Yates wrote:
Eric Jacobsen<eric.jacobsen at (no spam) ieee.org> writes:
[...]
This place is going to get really tiresome if every response to a
question has to include every possible nuance in the answer.

To make a statement that is not true in general but only in certain
special cases and not point out that it's only true in those special
cases is not a "nuance," in my opinion.

I don't think I did that. Perhaps you did, but it likely doesn't matter.

Eric Jacobsen<eric.jacobsen at (no spam) ieee.org> writes:

On 11/8/2009 5:53 PM, Randy Yates wrote:
Eric Jacobsen<eric.jacobsen at (no spam) ieee.org> writes:
[...]
This place is going to get really tiresome if every response to a
question has to include every possible nuance in the answer.
To make a statement that is not true in general but only in certain
special cases and not point out that it's only true in those special
cases is not a "nuance," in my opinion.
I don't think I did that. Perhaps you did, but it likely doesn't matter.

If it doesn't matter, then let's say you did.