what's Es/No mean?

What's Es/No mean? - Davy - 06:46 04-03-06

Hi all,

I am new to communication region.

We know that Eb/No means "the ratio of the transmitted signal energy
per bit to the noise spectrum density".

What's Es/No mean? And what's their difference?

Any suggestions will be appreciated!
Best regards,
Davy

Re: What's Es/No mean? - Bevan Weiss - 07:19 04-03-06

Instead of just giving you the answer, I'll step you through it
logically. Very simple of course.

If you were to transmit multiple bits, what would you call this multiple
bit transmission. ie those multiple bits would be encoded into a signal
transmitted s..... (the word will fit if the dots are replaced with the
correct letters)

Via phonic spelling it's also a percussion instrument.


Davy wrote:
> Hi all,
>
> I am new to communication region.
>
> We know that Eb/No means "the ratio of the transmitted signal energy
> per bit to the noise spectrum density".
>
> What's Es/No mean? And what's their difference?
>
> Any suggestions will be appreciated!
> Best regards,
> Davy
>

Re: What's Es/No mean? - john - 11:19 04-03-06

Bevan Weiss wrote:
> Instead of just giving you the answer, I'll step you through it
> logically. Very simple of course.
>
> If you were to transmit multiple bits, what would you call this multiple
> bit transmission. ie those multiple bits would be encoded into a signal
> transmitted s..... (the word will fit if the dots are replaced with the
> correct letters)
>
> Via phonic spelling it's also a percussion instrument.
>
>
> Davy wrote:
> > Hi all,
> >
> > I am new to communication region.
> >
> > We know that Eb/No means "the ratio of the transmitted signal energy
> > per bit to the noise spectrum density".
> >
> > What's Es/No mean? And what's their difference?
> >
> > Any suggestions will be appreciated!
> > Best regards,
> > Davy
> >

Another distinction -- in a system with FEC, Eb/No normally refers to
the *information* bits, before any FEC is applied. Es/No refers to the
*channel* symbols, after FEC is applied. The channel symbols may in
fact still be "bits" though.

For example, if a r=1/2, K=7 code is used with BPSK, a textbook might
show a BER vs Eb/No curve with two traces on it, coded and uncoded. The
uncoded one will have a 1e-5 BER at the familiar 9.6 dB Eb/No. The
coded one will hit 1e-5 BER at approx 4.5 dB Eb/No (just over 5 dB
gain). The Es/No for the coded case is actually 4.5 + 10*log10(r) = 1.5
dB.


John

Re: What's Es/No mean? - Almas_Uddin_Ahmed - 14:44 04-03-06

What's Es/No mean? And what's their difference?

it's mean symbol energy to noise ratio.

2.

symbol means a cllection of bit Es=nEb.

in digital communication
u can send your signal by bit (0/1) or symbol (0/1 s0 s1 for bpsk 00
010 10 11s0 s1 s2 s3 for qpsk so here eatch symbol represnt two bit)
it's totally up to u.

Re: What's Es/No mean? - mpoullet - 16:35 04-03-06

Hi,

You can have a look at :

http://www.sss-mag.com/ebn0.html

and replace "Energy per Bit (Eb)" with "Energy per Symbol (Es)" as
explained in the other answers.

Regards,

Matthieu

Re: What's Es/No mean? - Davy - 02:35 05-03-06

Hi john,

Thank you for your help!

A simple question:
Does 10*log10(rate) mean the code gain of BPSK modulation?
And is there code gain of QAM modulation?

Any suggestions will be appreciated!
Best regards,
Davy

Re: What's Es/No mean? - john - 05:50 05-03-06

Davy wrote:
> Hi john,
>
> Thank you for your help!
>
> A simple question:
> Does 10*log10(rate) mean the code gain of BPSK modulation?
> And is there code gain of QAM modulation?
>
> Any suggestions will be appreciated!
> Best regards,
> Davy

10*log10(rate) is the rate of the error correction code, expressed in
decibels. The rate of the code is the ratio of number of input bits to
number of output bits. For a convolutional code this is the inverse of
an integer, for example 1/2, 1/3, etc. It is important to take this
factor into account when comparing coded and uncoded systems, because
to be fair the coded system should be compared to the uncoded system
running at a lower bit rate.

Coding gain is achievable for QAM modulation.

John