What is Viterbi's claim to fame - only the Viterbi algorithm ?

Has  he invented any  other theorem or circuit or algorithm ?

He is a life fellow of ieee, right ?

What criteria is there to  promote from fellow to life fellow ?

              shankar

On 8 Aug 2003, kbc wrote:

> What is Viterbi's claim to fame - only the Viterbi algorithm ?
>

if "claim to fame" means "the one thing someone is most famous
for", i think this is correct.  but if you insinuate that it
is the only good thing he has contributed, then i disagree.

> Has  he invented any  other theorem or circuit or algorithm ?
>

plenty of things.  get a glimpse or two here:

  http://www.cparity.com/it/demo/welcome.htm
  http://ieeexplore.ieee.org

and do an author search on viterbi.

he made a lot of contribution to the idea of using CDMA and the
techniques required to make it to work for cellular communication.

plus, classical analysis for error performance of communication
systems, both in source coding and in channel coding.

> He is a life fellow of ieee, right ?
>

i think so.  and was fellow of ieee previously.

> What criteria is there to  promote from fellow to life fellow ?
>

i'm sure this is on the IEEE website somewhere!

julius

-- 
The most rigorous proofs will be shown by vigorous handwaving.
http://www.mit.edu/~kusuma

opinion of author is not necessarily of the institute

kbc wrote:
> 
> What is Viterbi's claim to fame - only the Viterbi algorithm ?
> 
> Has  he invented any  other theorem or circuit or algorithm ?
> 
> He is a life fellow of ieee, right ?
> 
> What criteria is there to  promote from fellow to life fellow ?
> 
>               shankar

Would you like me to teach you how to use Google? Viterbi's first name
is Andrew. Look it up.

Jerry
-- 
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������

What??????  dynamic programming" = "exhaustive search" ?????

The whole idea of dynamic programming is not to perform exhaustive search!!!
and to cut down the computational load!!!
By employing dynamic programming one prunes out most of the irrelevant search
possibilities, and by doing s one reduces the exhaustive search to a relatively very
small number of paths that the trellis or other specific grid structure allows.  In
simple Trellis having N stages of K points each, instead of N^K (power) possibilities
of exhaustive search, the dynamic programming may search only N*K paths.

Not sure whether Prof. Viterbi was the first one to invent dynamic programming, but he
definitely made it very useful and applicable for communications, and developed many
systems and concept based on it.

Dr.DSP


Peter Brackett wrote:
> 
> KBC:
> 
> [snip]
> "kbc" <kbc32@yahoo.com> wrote in message
> news:a382521e.0308072354.234834dc@posting.google.com...
> > What is Viterbi's claim to fame - only the Viterbi algorithm ?
> >
> > Has  he invented any  other theorem or circuit or algorithm ?
> >
> > He is a life fellow of ieee, right ?
> >
> > What criteria is there to  promote from fellow to life fellow ?
> >
> >               shankar
> [snip]
> 
> Andrew Viterbi has made many original contributions to communications
> technology.
> 
> Unfortunately the "one" which is named after him, the so-called "Viterbi
> Algorithm" is not
> a unique contribution of his, indeed it is not that unique.
> 
> Dave Forney wrote an IEEE Proceeding's article which named this algorithm
> the "Viterbi
> Algorithm".  Andrew Viterbi never called it that!
> 
> The so-called "Viterbi Algorithm" which is a maximum likelihood sequence
> estimation
> algorthim is nothing more nor less than an "exhaustive search" of all
> possible lattice
> paths seeking the one with the maximum likelihood!  Not very subtle!
> Exhaustive
> search is the "dumbest" of all possible optimization methods.  This
> technique of
> "exhaustive search" of all possible solutions until the optimum is found is
> often called
> "dynamic programming".  The so-called Viterbi Algorithm is nothing more nor
> less
> than the "dynamic programming" or "exhaustive search" algorithm.
> 
> Nothing unique, novel or subtle about it!  Just search over all possible
> solutions
> and then choose the one with the least cost!
> 
> Just as with Einstein, who never won an award for "Relativity" but did win
> awards
> for lesser  works, Andrew Viterbi is unfortunately remembered by having his
> name
> attached to an algorithm which he did not invent and which was not even
> novel
> or unique, and this unfortunate circumstance was perpetrated by another
> person
> [Dave Forney] writing an article about the exhaustive search algorithm and
> calling
> it the Viterbi Algorthim simply because Andrew Viterbi had suggested doing
> an
> exhautive search!
> 
> So much for celebrity.
> 
> OTOH... any literature search will uncover the many unique contributions of
> Andrew Viterbi to communications sciences!  It's just that the only one
> named
> for him is not that important and was not even discovered or invented by
> him!
> 
> --
> Peter
> Consultant
> Indialantic By-the-Sea, FL.

"Peter Brackett" <ab4bc@ix.netcom.com> wrote in message
news:bh1c9g$e7e$1@slb9.atl.mindspring.net...
> Just as with Einstein, who never won an award for "Relativity" but did win
> awards
> for lesser  works, > --
> Peter
> Consultant
> Indialantic By-the-Sea, FL.
>

Peter,

The example with Einstein is a bad one since the Nobel prize has an
advancement of technology requirement which is much more appropriate to his
explanation of the photoelectric effect, which is by the way what he won the
Nobel prize for. While Lorentz and Poincare did a lot for the math behind
relativity, Einstein took it much furthur than anyone else at the time and
thusly did a lot of original work. But there was no application to
technology (then) so there was no prize. So I wouldn't say he got the prize
for a lessor work, but rather for a more applicable to the rules of the
prize committee work.

Clay

>
>

i dont have half hour to spend on this.

what do u think is the purpose of a newsgroup ?


Jerry Avins <jya@ieee.org> wrote in message news:<3F33D038.2241D50F@ieee.org>...
> kbc wrote:
> > 
> > What is Viterbi's claim to fame - only the Viterbi algorithm ?
> > 
> > Has  he invented any  other theorem or circuit or algorithm ?
> > 
> > He is a life fellow of ieee, right ?
> > 
> > What criteria is there to  promote from fellow to life fellow ?
> > 
> >               shankar
> 
> Would you like me to teach you how to use Google? Viterbi's first name
> is Andrew. Look it up.
> 
> Jerry

Santosh:

The so-called VA or Viterbi Algorith for maximum likelihood sequence
estimation
is nothing more than the technique of traversing *all* paths through the
[decoding]
lattice while calculating and recording the probability of each path
matching the
correct one.

At the appropriate time the path with the highest probablility is chosen.
i.e. the VA
is simply an exhaustive search of all possible lattice paths to find the one
path most likely.

Of all the different techniques for mathematical optimization, exhaustive
search is the
least subtle and least efficient.  Examine *all* of the possible outcomes
and pick the
best one.   No shortcuts!

The so-called VA is not a very subtle method of optimization, but it's all
that is
available for this particular communications problem!

Taking nothing away from either of Andrew Viterbi or Dave Forney, but...
IMHO using
the "fancy" name ["VA"] for what is simply an "exhautive search" is
misleading to students
who first encounter it's use.  i.e. It would be better to tell simply tell
beginning students of
decoding methods, we "do an exhaustive search" rather than we "do the
Viterbi Algorithm".

Later one could tell the student that "do an exhaustive search of the
lattice" was
"named" the "Viterbi Algorithm" in honor of Andrew Viterbi by Dave Forney
since Viterbi
was the one who first proposed doing an exhaustive search of the lattice to
find the "best"
estimate for the transmitted sequence!

BTW... is that not what any simple minded lay person would have proposed
doing?
It surely doesn't take a Ph.D Professor to propose searching everything to
find the best!

The VA... a "tempest in a teapot", "much ado about nothing", or... "what's
in a name?"

I am sure that Andrew Viterbi would much rather have had Dave Forney name
any of his
other more important contributions to communications science after him.

BTW... I have the same complaint about the "name" Hertz [Hz], was not the
older
term "cycles per second" more appropriate and more easily understood by
beginning
students.

Yes I agree that we must "honor" the "Masters" but do we have to rename the
obvious?

Thoughts, comments?

:-)

--
Peter
Consultant
Indialantic By-the-Sea, FL.


"santosh nath" <santosh.nath@ntlworld.com> wrote in message
news:6afd943a.0308082323.3c6792a5@posting.google.com...
> "Peter Brackett" <ab4bc@ix.netcom.com> wrote in message
news:<bh1c9g$e7e$1@slb9.atl.mindspring.net>...
> > KBC:
> >
> > [snip]
> > "kbc" <kbc32@yahoo.com> wrote in message
> > news:a382521e.0308072354.234834dc@posting.google.com...
> > > What is Viterbi's claim to fame - only the Viterbi algorithm ?
> > >
> > > Has  he invented any  other theorem or circuit or algorithm ?
> > >
> > > He is a life fellow of ieee, right ?
> > >
> > > What criteria is there to  promote from fellow to life fellow ?
> > >
> > >               shankar
> > [snip]
> >
> > Andrew Viterbi has made many original contributions to communications
> > technology.
> >
> > Unfortunately the "one" which is named after him, the so-called "Viterbi
> > Algorithm" is not
> > a unique contribution of his, indeed it is not that unique.
> >
> > Dave Forney wrote an IEEE Proceeding's article which named this
algorithm
> > the "Viterbi
> > Algorithm".  Andrew Viterbi never called it that!
>
> Hi Peter,
>
> G. David Forney,Jr, a MIT Phd, is one of the pioneers of modern
> communication theory. Viterbi has to be grateful to him since he
> introduced the representation of convolutional codes by trellis
> diagrams, and proved the optimality of the Viterbi algorithm. I think
> he also introduced the idea of concatenated convolution codes and
> contributed towards serially concatenated codes(?). Turbo codes  , on
> the other handhand,  has paralell concatenation with intermidiate
> interleaver and gained the attention of the industry very rapidly. He
> is also one of the pioneers to introduce  veterbi equalizer (not same
> as decoder!!) to mitigate ISI from the fading channels.
>
> Secondly, why you guys are not mentioning Marcov(for Hidden Marcov
> Model) since
> Viterbi algorithm is  a special case of HMM with simple assumptions
> -is n't?
>
> Regards,
> Santosh
>
>
>
>
> >
> > The so-called "Viterbi Algorithm" which is a maximum likelihood sequence
> > estimation
> > algorthim is nothing more nor less than an "exhaustive search" of all
> > possible lattice
> > paths seeking the one with the maximum likelihood!  Not very subtle!
> > Exhaustive
> > search is the "dumbest" of all possible optimization methods.  This
> > technique of
> > "exhaustive search" of all possible solutions until the optimum is found
is
> > often called
> > "dynamic programming".  The so-called Viterbi Algorithm is nothing more
nor
> > less
> > than the "dynamic programming" or "exhaustive search" algorithm.
> >
> > Nothing unique, novel or subtle about it!  Just search over all possible
> > solutions
> > and then choose the one with the least cost!
> >
> > Just as with Einstein, who never won an award for "Relativity" but did
win
> > awards
> > for lesser  works, Andrew Viterbi is unfortunately remembered by having
his
> > name
> > attached to an algorithm which he did not invent and which was not even
> > novel
> > or unique, and this unfortunate circumstance was perpetrated by another
> > person
> > [Dave Forney] writing an article about the exhaustive search algorithm
and
> > calling
> > it the Viterbi Algorthim simply because Andrew Viterbi had suggested
doing
> > an
> > exhautive search!
> >
> > So much for celebrity.
> >
> > OTOH... any literature search will uncover the many unique contributions
of
> > Andrew Viterbi to communications sciences!  It's just that the only one
> > named
> > for him is not that important and was not even discovered or invented by
> > him!

On 9 Aug 2003 00:23:36 -0700, santosh.nath@ntlworld.com (santosh nath)
wrote:

>Hi Peter,
>
>G. David Forney,Jr, a MIT Phd, is one of the pioneers of modern
>communication theory. Viterbi has to be grateful to him since he
>introduced the representation of convolutional codes by trellis
>diagrams, and proved the optimality of the Viterbi algorithm. I think
>he also introduced the idea of concatenated convolution codes and
>contributed towards serially concatenated codes(?). Turbo codes  , on
>the other handhand,  has paralell concatenation with intermidiate
>interleaver and gained the attention of the industry very rapidly. He
>is also one of the pioneers to introduce  veterbi equalizer (not same
>as decoder!!) to mitigate ISI from the fading channels.

Santosh,

Code concatenation has been around for a long, long time, both
parallel and serial.   Turbo Codes come in both parallel and serial
flavors, and although they've gained a lot of attention they're still
not very widely used because of the complexity and latency issues
associated with them.  I think other codes may surpass Turbo Codes in
many applications in the future.

I think the contributions you were alluding to were mostly analysis
and performance related, not really seminally defining concatenation.


Eric Jacobsen
Minister of Algorithms, Intel Corp.
My opinions may not be Intel's opinions.
http://www.ericjacobsen.org

kbc wrote:
> 
> i dont have half hour to spend on this.
> 
> what do u think is the purpose of a newsgroup ?

Whatever a newsgroup's purpose, it is not to save you ten minutes by
having five people spend ten minutes each. Keep in mind that comp.dsp is
not a subscription service. Every answer you get is from someone being
generous. I won't presume to speak for God, but I tend to help those who
at least try to help themselves.

Your question sounded very much like a veiled way to ask "Who the hell
is this Viterbi guy anyway, that he should be a Life Fellow of the
IEEE?" At any rate, disdain came across to me whether you intended it or
not. One is elected to the honor of Fellow for one's achievements. The
"Life" part comes automatically, from living long enough. I am a Life
Member of the IEEE. All that really means is that I don't have to pay
dues any more. (I'm also a charter member, but that's another matter.)

Jerry
-- 
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������
> Jerry Avins <jya@ieee.org> wrote in message news:<3F33D038.2241D50F@ieee.org>...
> > kbc wrote:
> > >
> > > What is Viterbi's claim to fame - only the Viterbi algorithm ?
> > >
> > > Has  he invented any  other theorem or circuit or algorithm ?
> > >
> > > He is a life fellow of ieee, right ?
> > >
> > > What criteria is there to  promote from fellow to life fellow ?
> > >
> > >               shankar
> >
> > Would you like me to teach you how to use Google? Viterbi's first name
> > is Andrew. Look it up.
> >
> > Jerry

Peter Brackett wrote:
> 
  ...
> 
> BTW... I have the same complaint about the "name" Hertz [Hz], was not the
> older
> term "cycles per second" more appropriate and more easily understood by
> beginning
> students.
> 
> Yes I agree that we must "honor" the "Masters" but do we have to rename the
> obvious?
> 
> Thoughts, comments?
> 
For the unit of frequency, it would have been better to honor Steinmetz,
the proponent of AC power distribution (Edison championed DC). Then we
could have used his initials and achieved continuity. His full name, of
course, was Charles Proteus Steinmetz.

Jerry
-- 
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������

On Fri, 08 Aug 2003 20:38:21 -0400, Peter Brackett wrote:
> The so-called Viterbi Algorithm is nothing more nor less
> than the "dynamic programming" or "exhaustive search" algorithm.

Dynamic programming and exhaustive search are two different animals.

Exhaustive search does what the name says, and chooses the "best" out of
all possibilities.

Dynamic programming is an algorithm design technique for problems that
have overlapping subproblems.  The "programming" in this cases means that
there is some bookkeeping done that tracks progress, and guides the
algorithm for what to do next.

Basically, if a problem has non-overlapping subproblems, then
divide-and-conquer will be best.  If the subproblems overlap, then dynamic
programming will be best.  If there are no subproblems, then exhaustive
search is the only option.

-- 
Matthew Donadio (m.p.donadio@ieee.org)

"santosh nath" <santosh.nath@ntlworld.com> wrote in message
news:6afd943a.0308082323.3c6792a5@posting.google.com...

To give one more example that shows the case where the developer's name is
being used as its name, I add a story to Santosh's.

> I think
> he also introduced the idea of concatenated convolution codes and
> contributed towards serially concatenated codes(?). Turbo codes  , on
> the other handhand,  has paralell concatenation with intermidiate
> interleaver and gained the attention of the industry very rapidly.

About Turbo codes, which is first introduced by Berrou, Claude ;
Glavieux, Alain ; Thitimajshima, Punya on ICC confernce, 1993.
As its rapid attention was noted by Santosh, it was aceepted as the FEC
method on
W-CDMA standard. Furthermore, one of its popular decoder is called as BCJR
decoder
after developers Bahl, Cocke, Jelinek, and Rajiv. This case seems very
simular
to that of Viterbi decoder, which has been a topic of this dicussion.

> Regards,
> Santosh

Briefly, I introduced more details on Turbo codes, especially developers and
its great attention, and one note similar to the situation of Vierbi
decoder,
which story is related to a decoder for Turbo codes.

-- 
Regards,
---
James (txdiversity@hotmail.com)
- Private opinions: These are not the opinions from my affiliation.

eric.jacobsen@ieee.org (Eric Jacobsen) wrote in message news:<3f3555da.257141773@news.earthlink.net>...
> On 9 Aug 2003 00:23:36 -0700, santosh.nath@ntlworld.com (santosh nath)
> wrote:
> 
> >Hi Peter,
> >
> >G. David Forney,Jr, a MIT Phd, is one of the pioneers of modern
> >communication theory. Viterbi has to be grateful to him since he
> >introduced the representation of convolutional codes by trellis
> >diagrams, and proved the optimality of the Viterbi algorithm. I think
> >he also introduced the idea of concatenated convolution codes and
> >contributed towards serially concatenated codes(?). Turbo codes  , on
> >the other handhand,  has paralell concatenation with intermidiate
> >interleaver and gained the attention of the industry very rapidly. He
> >is also one of the pioneers to introduce  veterbi equalizer (not same
> >as decoder!!) to mitigate ISI from the fading channels.
> 
> Santosh,
> 
> Code concatenation has been around for a long, long time, both
> parallel and serial.   Turbo Codes come in both parallel and serial
> flavors, and although they've gained a lot of attention they're still
> not very widely used because of the complexity and latency issues
> associated with them.  I think other codes may surpass Turbo Codes in
> many applications in the future.



Hi Eric,

I have some points which could differ with you article.
We started with Viterbi algorithm- and I mentioned convolution
encoding as
serial or paralell concantention - the reason could be viterbi decoder
is the
most popular optimum decoding scheme for convolution encoders. Could
you name the person who claim to introduce serial concantention
convolution codes before G.D. Forney?

Paralell concantention convolution codes  is termed as "full turbo
coder" as introduced by Berrou et al. I think the term "full" refers
here  iterative
decoder having two APP detectors required for the turbo encoder only
and no other encoders and decoders are supposed to be introduced in
the system.

Now coming to serial concantention issue is rather interesting
investiagted by
Ryan et al for Partial response channel class4(PR4). Here, the outer
encoder is turbo encoder (so as if it is a single encoder) and inner
encoder is PR4 encoder and it is veiwed as a serial concantention. In
the decoding side turbo decoder is outer decoding unit and separate
APP is used for PR channel:

Requirement in PR4: 1. Two paralell convolution encoders and one PR4
encoder
                    2. Three APP detectors in decoding side.

If I am not wrong wideband DS-CDMA for UMTS uses "full turbo codes"
i.e paralell concantention as standard process(James also mentioned
the same thing).

Coming to complexity issue- I guess the Berrou group has come up with
decicated
turbo coder on ASIC so if the computation complexity is consumed by HW
then is it still a problem for commercialization? - I guess somebody
can update us more on the recent implemenations of the turbo coder.

santosh

> 
> I think the contributions you were alluding to were mostly analysis
> and performance related, not really seminally defining concatenation.
> 
> 
> Eric Jacobsen
> Minister of Algorithms, Intel Corp.
> My opinions may not be Intel's opinions.
> http://www.ericjacobsen.org

Jerry Avins <jya@ieee.org> wrote in message news:<3F356F53.4E1F3459@ieee.org>...
> Peter Brackett wrote:
> > 
>  ...
> > 
> > BTW... I have the same complaint about the "name" Hertz [Hz], was not the
> > older
> > term "cycles per second" more appropriate and more easily understood by
> > beginning
> > students.
> > 
> > Yes I agree that we must "honor" the "Masters" but do we have to rename the
> > obvious?
> > 
> > Thoughts, comments?
> > 
> For the unit of frequency, it would have been better to honor Steinmetz,
> the proponent of AC power distribution (Edison championed DC). Then we
> could have used his initials and achieved continuity. His full name, of
> course, was Charles Proteus Steinmetz.
> 
> Jerry

While I am sure there may be many opinions regarding what individuals 
should be honored in this fashion, using people's names for designating 
units isn't a very bad idea.

Names are international as opposed to "sentences" like "cycles per second".
I'm not sure "cycles per second" is as obvious to everyone who don't have
English as their native language (or at least people who's native languages 
don't belong to the indo-european family).

Rune

On Fri, 8 Aug 2003 21:42:26 -0400, "Clay S. Turner"
<physicsNOOOOSPPPPAMMMM@bellsouth.net> wrote:

>
>"Peter Brackett" <ab4bc@ix.netcom.com> wrote in message
>news:bh1c9g$e7e$1@slb9.atl.mindspring.net...
>> Just as with Einstein, who never won an award for "Relativity" but did win
>> awards
>> for lesser  works, > --
>> Peter
>> Consultant
>> Indialantic By-the-Sea, FL.
>>
>
>Peter,
>
>The example with Einstein is a bad one since the Nobel prize has an
>advancement of technology requirement which is much more appropriate to his
>explanation of the photoelectric effect, which is by the way what he won the
>Nobel prize for. While Lorentz and Poincare did a lot for the math behind
>relativity, Einstein took it much furthur than anyone else at the time and
>thusly did a lot of original work. But there was no application to
>technology (then) so there was no prize. So I wouldn't say he got the prize
>for a lessor work, but rather for a more applicable to the rules of the
>prize committee work.
>
>Clay

Hi Clay,
  I once read that Eistein was so confident that 
he'd win the next Nobel prize, that he included the 
not-yet-awarded prize money (to be given to his ex-wife) 
in his Divorce Decree.  

[-Rick-]

Part of Eric's message:
> > Santosh,
> > 
> > Code concatenation has been around for a long, long time, both
> > parallel and serial.   Turbo Codes come in both parallel and serial
> > flavors, and although they've gained a lot of attention they're still
> > not very widely used because of the complexity and latency issues
> > associated with them.  I think other codes may surpass Turbo Codes in
> > many applications in the future.

Part of Santosh's reply:> 
> Coming to complexity issue- I guess the Berrou group has come up with
> decicated
> turbo coder on ASIC so if the computation complexity is consumed by HW
> then is it still a problem for commercialization? - I guess somebody
> can update us more on the recent implemenations of the turbo coder.
> 
I guess I will be digressing  further from the original post. As Eric
said Turbo codes will be replaced. One potential candidate is Low
Density Parity Check Codes. You can do a quick search on LDPC in
IEEExplore. In summary LDPC codes are more easy to implement in
hardware due to the fact that they have massive parallelism.

Yes there are ASIC implementation of Turbo but they don't perform well
in terms of power. Turbo codes and low-density parity check (LDPC)
codes are two general classes of practical codes which can achieve
near Shannon limit ECC. Turbo codes received lot of attention but they
are computationally expensive to decode and don't support parallelism,
which is amenable to hardware implementation. There is a lot more room
for parallelism in the LDPC decoding than in the turbo-decoding
algorithm.

The research on finding better LDPC codes and adapting for them for
different wireless ,storage and network applications is getting
popular in academia(e.g. Texas A&M (wcl.tamu.edu), Berkeley
(http://bwrc.eecs.berkeley.edu) as well as in industry (eg.
Flarion,Agere)

-Choudhary

Rune Allnor wrote:

> Jerry Avins <jya@ieee.org> wrote in message news:<3F356F53.4E1F3459@ieee.org>...
> 
>>Peter Brackett wrote:
>>
>> ...
>>
>>>BTW... I have the same complaint about the "name" Hertz [Hz], was not the
>>>older
>>>term "cycles per second" more appropriate and more easily understood by
>>>beginning
>>>students.
>>>
>>>Yes I agree that we must "honor" the "Masters" but do we have to rename the
>>>obvious?
>>>
>>>Thoughts, comments?
>>>
>>
>>For the unit of frequency, it would have been better to honor Steinmetz,
>>the proponent of AC power distribution (Edison championed DC). Then we
>>could have used his initials and achieved continuity. His full name, of
>>course, was Charles Proteus Steinmetz.
>>
>>Jerry
> 
> 
> While I am sure there may be many opinions regarding what individuals 
> should be honored in this fashion, using people's names for designating 
> units isn't a very bad idea.
> 
> Names are international as opposed to "sentences" like "cycles per second".
> I'm not sure "cycles per second" is as obvious to everyone who don't have
> English as their native language (or at least people who's native languages 
> don't belong to the indo-european family).
> 

I think you missed the punch line there Rune - read the last sentence 
again. ;-)

(Of course young 'uns may never have heard of cps ;-)).

Paul

On 10 Aug 2003 02:08:10 -0700, santosh.nath@ntlworld.com (santosh
nath) wrote:

>eric.jacobsen@ieee.org (Eric Jacobsen) wrote in message news:<3f3555da.257141773@news.earthlink.net>...
>> On 9 Aug 2003 00:23:36 -0700, santosh.nath@ntlworld.com (santosh nath)
>> wrote:

>> Santosh,
>> 
>> Code concatenation has been around for a long, long time, both
>> parallel and serial.   Turbo Codes come in both parallel and serial
>> flavors, and although they've gained a lot of attention they're still
>> not very widely used because of the complexity and latency issues
>> associated with them.  I think other codes may surpass Turbo Codes in
>> many applications in the future.
>
>
>
>Hi Eric,
>
>I have some points which could differ with you article.
>We started with Viterbi algorithm- and I mentioned convolution
>encoding as
>serial or paralell concantention - the reason could be viterbi decoder
>is the
>most popular optimum decoding scheme for convolution encoders. Could
>you name the person who claim to introduce serial concantention
>convolution codes before G.D. Forney?

For the specific case of convolutional codes I don't know, but serial
concatenation of codes, which is all I was addressing, has been around
much longer than that.

>Paralell concantention convolution codes  is termed as "full turbo
>coder" as introduced by Berrou et al. I think the term "full" refers
>here  iterative
>decoder having two APP detectors required for the turbo encoder only
>and no other encoders and decoders are supposed to be introduced in
>the system.

I'm not quite sure what you're trying to say here.  I've never heard
the term "full turbo coder" before, and I don't know what an APP
detector is, either, especially not in the encoder.

APP decoders (also called MAP decoders, or implementations of the BCJR
algorithm) are typically used to decode convolutional turbo codes, but
that's true for both parallel and serial concatenated turbo codes with
convolutional constituent codes.

>Now coming to serial concantention issue is rather interesting
>investiagted by
>Ryan et al for Partial response channel class4(PR4). Here, the outer
>encoder is turbo encoder (so as if it is a single encoder) and inner
>encoder is PR4 encoder and it is veiwed as a serial concantention. In
>the decoding side turbo decoder is outer decoding unit and separate
>APP is used for PR channel:
>
>Requirement in PR4: 1. Two paralell convolution encoders and one PR4
>encoder
>                    2. Three APP detectors in decoding side.
>
>If I am not wrong wideband DS-CDMA for UMTS uses "full turbo codes"
>i.e paralell concantention as standard process(James also mentioned
>the same thing).

Yes, there is a 3GPP standardization of a parallel convolutional turbo
code, there is also a DVB-RCS standardization of a duo-binary
convolutional turbo code.  There may be others.

>Coming to complexity issue- I guess the Berrou group has come up with
>decicated
>turbo coder on ASIC so if the computation complexity is consumed by HW
>then is it still a problem for commercialization? - I guess somebody
>can update us more on the recent implemenations of the turbo coder.

France Telecom started working with Berrou's students very early on
and there were ASIC solutions for turbo decoding quite a few years
ago.  Several used SOVA decoders instead of APPs in order to save
complexity, and these also reduced the performance a little bit.
There have been other silicon solutions since, and my group at a
previous employer built a hardware prototype for a flexible Turbo Code
for satellite applications about four years ago.  Hardware solutions
have been around, they've just not been efficient.  Turbo codes also
have the so-called "error floor" (which is really a slope change) and
this seems to prevent their acceptance in some applications.


Eric Jacobsen
Minister of Algorithms, Intel Corp.
My opinions may not be Intel's opinions.
http://www.ericjacobsen.org

On Sat, 09 Aug 2003 18:01:55 -0400, Jerry Avins <jya@ieee.org> wrote:

>Peter Brackett wrote:
>> 
>  ...
>> 
>> BTW... I have the same complaint about the "name" Hertz [Hz], was not the
>> older
>> term "cycles per second" more appropriate and more easily understood by
>> beginning
>> students.
>> 
>> Yes I agree that we must "honor" the "Masters" but do we have to rename the
>> obvious?
>> 
>> Thoughts, comments?
>> 
>For the unit of frequency, it would have been better to honor Steinmetz,
>the proponent of AC power distribution (Edison championed DC). Then we
>could have used his initials and achieved continuity. His full name, of
>course, was Charles Proteus Steinmetz.
>
>Jerry

An old boss of mine, who was quite a character, told me of CPS to
Hertz conversion charts that were popular during the transition in the
terminology.  Wags would hand them out to people as a joke and
statement regarding the intellect of the receiver;  one axis was on a
log scale and one on a linear so that the conversion was on a curve.

I always thought that was pretty funny, actually...


Eric Jacobsen
Minister of Algorithms, Intel Corp.
My opinions may not be Intel's opinions.
http://www.ericjacobsen.org

Jerry Avins <jya@ieee.org> wrote in message news:<3F356D97.2C9C7F4F@ieee.org>...

> 
> Whatever a newsgroup's purpose, it is not to save you ten minutes by
> having five people spend ten minutes each. Keep in mind that comp.dsp is
> not a subscription service. Every answer you get is from someone being
> generous. I won't presume to speak for God, but I tend to help those who
> at least try to help themselves.
> 
> Your question sounded very much like a veiled way to ask "Who the hell
> is this Viterbi guy anyway, that he should be a Life Fellow of the
> IEEE?" At any rate, disdain came across to me whether you intended it or
> not. One is elected to the honor of Fellow for one's achievements. The
> "Life" part comes automatically, from living long enough. I am a Life
> Member of the IEEE. All that really means is that I don't have to pay
> dues any more. (I'm also a charter member, but that's another matter.)
> 
> Jerry
> -- 
> Engineering is the art of making what you want from things you can get.


Troll  and hence ignoring.

Looks like you have some problem.

"kbc" <kbc32@yahoo.com> ha scritto nel messaggio
> Troll  and hence ignoring.
> Looks like you have some problem.
For sure, you are unable to quote decently, my dear, impolite
kbc32@yahoo.com

E.

Paul Russell <prussell@sonic.net> wrote in message news:<HzAZa.10394$dk4.415388@typhoon.sonic.net>...
> Rune Allnor wrote:
> 
> > Jerry Avins <jya@ieee.org> wrote in message news:<3F356F53.4E1F3459@ieee.org>...
> > 
> >>Peter Brackett wrote:
> >>
> >> ...
> >>
> >>>BTW... I have the same complaint about the "name" Hertz [Hz], was not the
> >>>older
> >>>term "cycles per second" more appropriate and more easily understood by
> >>>beginning
> >>>students.
> >>>
> >>>Yes I agree that we must "honor" the "Masters" but do we have to rename the
> >>>obvious?
> >>>
> >>>Thoughts, comments?
> >>>
> >>
> >>For the unit of frequency, it would have been better to honor Steinmetz,
> >>the proponent of AC power distribution (Edison championed DC). Then we
> >>could have used his initials and achieved continuity. His full name, of
> >>course, was Charles Proteus Steinmetz.
> >>
> >>Jerry
> > 
> > 
> > While I am sure there may be many opinions regarding what individuals 
> > should be honored in this fashion, using people's names for designating 
> > units isn't a very bad idea.
> > 
> > Names are international as opposed to "sentences" like "cycles per second".
> > I'm not sure "cycles per second" is as obvious to everyone who don't have
> > English as their native language (or at least people who's native languages 
> > don't belong to the indo-european family).
> > 
> 
> I think you missed the punch line there Rune - read the last sentence 
> again. ;-)
> 
> (Of course young 'uns may never have heard of cps ;-)).

I saw it, all right. 

Actually, I've seen old Norwegian documents that uses "cykler per sekund"
or "cps". Although "good" Norwegian ortography has changed quite a bit over 
the last century or so, I think "cps" appears somewhat artificial. I would 
have said "perioder per sekund", since "cykler" (plural of "cyclus") probably 
should be spelled "sykler", (Lat. cyclus -> Norw. syklus), which happens to 
be how the plural form of "sykkel" ("bicycle") is spelled.

Anyway, having a unit designated composed by initials of the honouree 
that by incident matches a nice acronym for an explanation of what's going 
on, would be nice. Provided one is familiar with the language the explanation 
is formulated in. I'm not sure I would very happy with such a convention if 
the language to be used would be Russian, Arabic or Chinese, which I don't 
know. 

Nah, I prefer the names.

Rune

> Paul

eric.jacobsen@ieee.org (Eric Jacobsen) wrote in message news:<3f36e7d7.359999617@news.earthlink.net>...
> On 10 Aug 2003 02:08:10 -0700, santosh.nath@ntlworld.com (santosh
> nath) wrote:
> 
> >eric.jacobsen@ieee.org (Eric Jacobsen) wrote in message news:<3f3555da.257141773@news.earthlink.net>...
> >> On 9 Aug 2003 00:23:36 -0700, santosh.nath@ntlworld.com (santosh nath)
> >> wrote:
>  
> >> Santosh,
> >> 
> >> Code concatenation has been around for a long, long time, both
> >> parallel and serial.   Turbo Codes come in both parallel and serial
> >> flavors, and although they've gained a lot of attention they're still
> >> not very widely used because of the complexity and latency issues
> >> associated with them.  I think other codes may surpass Turbo Codes in
> >> many applications in the future.
> >
> >
> >
> >Hi Eric,
> >
> >I have some points which could differ with you article.
> >We started with Viterbi algorithm- and I mentioned convolution
> >encoding as
> >serial or paralell concantention - the reason could be viterbi decoder
> >is the
> >most popular optimum decoding scheme for convolution encoders. Could
> >you name the person who claim to introduce serial concantention
> >convolution codes before G.D. Forney?
> 
> For the specific case of convolutional codes I don't know, but serial
> concatenation of codes, which is all I was addressing, has been around
> much longer than that.
> 
> >Paralell concantention convolution codes  is termed as "full turbo
> >coder" as introduced by Berrou et al. I think the term "full" refers
> >here  iterative
> >decoder having two APP detectors required for the turbo encoder only
> >and no other encoders and decoders are supposed to be introduced in
> >the system.
> 
> I'm not quite sure what you're trying to say here.  I've never heard
> the term "full turbo coder" before, and I don't know what an APP
> detector is, either, especially not in the encoder.
> 
> APP decoders (also called MAP decoders, or implementations of the BCJR
> algorithm) are typically used to decode convolutional turbo codes, but
> that's true for both parallel and serial concatenated turbo codes with
> convolutional constituent codes.


I agree -it is not very popular to use detectors instead of decoders
for this particular system - the former one is more genric. But, some
papers  use  detector instead of decoder because of the following
probable reason:

Since turbo decoder is a decoding system itself containing two APP
decoders
it is not a bad idea two call them as detectors to distinguish from
system decoder. I guess I have not mentioned APP at encoder side -if
that means to
you it is my mistake of forming poor sentence.

Conclusion: detector and decoder carries the same meaning in my post.

"Full" means the encoding and  decoding system is entirely turbo
based. As I specified Ryan et al used separarte inner encoder serially
concatenated with
turbo encoder the system is an example of serial concatenation - but
it is mixed.

I am not sure whether Berrou originally proposed both paralell and
Serial concatenation turbo codes - I guess it was paralell only(!)

It would be interesting if you could tell something about performance
comparision of both serial and paralell turbo codes and also bit in
their
complexity sides.

Regards,
Santosh




> 
> >Now coming to serial concantention issue is rather interesting
> >investiagted by
> >Ryan et al for Partial response channel class4(PR4). Here, the outer
> >encoder is turbo encoder (so as if it is a single encoder) and inner
> >encoder is PR4 encoder and it is veiwed as a serial concantention. In
> >the decoding side turbo decoder is outer decoding unit and separate
> >APP is used for PR channel:
> >
> >Requirement in PR4: 1. Two paralell convolution encoders and one PR4
> >encoder
> >                    2. Three APP detectors in decoding side.
> >
> >If I am not wrong wideband DS-CDMA for UMTS uses "full turbo codes"
> >i.e paralell concantention as standard process(James also mentioned
> >the same thing).
> 
> Yes, there is a 3GPP standardization of a parallel convolutional turbo
> code, there is also a DVB-RCS standardization of a duo-binary
> convolutional turbo code.  There may be others.
> 
> >Coming to complexity issue- I guess the Berrou group has come up with
> >decicated
> >turbo coder on ASIC so if the computation complexity is consumed by HW
> >then is it still a problem for commercialization? - I guess somebody
> >can update us more on the recent implemenations of the turbo coder.
> 
> France Telecom started working with Berrou's students very early on
> and there were ASIC solutions for turbo decoding quite a few years
> ago.  Several used SOVA decoders instead of APPs in order to save
> complexity, and these also reduced the performance a little bit.
> There have been other silicon solutions since, and my group at a
> previous employer built a hardware prototype for a flexible Turbo Code
> for satellite applications about four years ago.  Hardware solutions
> have been around, they've just not been efficient.  Turbo codes also
> have the so-called "error floor" (which is really a slope change) and
> this seems to prevent their acceptance in some applications.
> 
> 
> Eric Jacobsen
> Minister of Algorithms, Intel Corp.
> My opinions may not be Intel's opinions.
> http://www.ericjacobsen.org

The less neat something really is, is the more it needs a good name.

When someone says "how does your error handling work" do you really want 
to say "the receiver gropes around in the dark, trying endless 
possibilities, until it stumbles on its best guess at the actual 
transmitted data". Isn't "we use Viterbi techniques to evaluate the 
maximum likelihood sequence" better? Better still "we use Viterbi 
techniques to evaulate the MLS" avoids a phrase that still sounds like 
vague guessing.

Regards
Steve


Peter Brackett wrote:
> 
> OTOH... any literature search will uncover the many unique contributions of
> Andrew Viterbi to communications sciences!  It's just that the only one
> named
> for him is not that important and was not even discovered or invented by
> him!

Paul Russell wrote:
> 
> I think you missed the punch line there Rune - read the last sentence
> again. ;-)
> 
> (Of course young 'uns may never have heard of cps ;-)).

And speaking of punch-lines, for those who haven't heard of cps, I have
assembled a handy-dandy conversion chart:

http://leesburg.bittware.com/hz2cps.html

;-)

-- 
Jim Thomas            Principal Applications Engineer  Bittware, Inc
jthomas@bittware.com  http://www.bittware.com          (703) 779-7770
I'm a man.  But I can change.  If I have to.  I guess.  - Red Green

Jim Thomas wrote:

> And speaking of punch-lines, for those who haven't heard of cps, I have
> assembled a handy-dandy conversion chart:
> 
> http://leesburg.bittware.com/hz2cps.html

I guess, to convert noninteger Hz, like 100.5,
a linear interpolation would be enough... ;-)

bye,

-- 
   Piergiorgio Sartor

Rune Allnor wrote:
>>
>>I think you missed the punch line there Rune - read the last sentence 
>>again. ;-)
>>
>>(Of course young 'uns may never have heard of cps ;-)).
> 
> 
> I saw it, all right. 
> 

My bad - If I had read more carefully before posting I would have 
realised this.

Regards,

Paul

Jim Thomas wrote:

> Paul Russell wrote:
> 
>>I think you missed the punch line there Rune - read the last sentence
>>again. ;-)
>>
>>(Of course young 'uns may never have heard of cps ;-)).
> 
> 
> And speaking of punch-lines, for those who haven't heard of cps, I have
> assembled a handy-dandy conversion chart:
> 
> http://leesburg.bittware.com/hz2cps.html
> 

This is also quite a straightforward operation on a slide rule, if you 
don't happen to have the conversion chart handy. ;-)

Paul

Steve Underwood wrote:
> 
> The less neat something really is, is the more it needs a good name.
> 
> When someone says "how does your error handling work" do you really want
> to say "the receiver gropes around in the dark, trying endless
> possibilities, until it stumbles on its best guess at the actual
> transmitted data". Isn't "we use Viterbi techniques to evaluate the
> maximum likelihood sequence" better? Better still "we use Viterbi
> techniques to evaulate the MLS" avoids a phrase that still sounds like
> vague guessing.
> 
> Regards
> Steve
> 
> Peter Brackett wrote:
> >
> > OTOH... any literature search will uncover the many unique contributions of
> > Andrew Viterbi to communications sciences!  It's just that the only one
> > named
> > for him is not that important and was not even discovered or invented by
> > him!

I don't know about the last improvement. Whenever I see "MLS", I think
"PMS". I don't know why.

Jerry
-- 
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������

On Mon, 11 Aug 2003 02:03:16 -0700, kbc wrote:
> Troll  and hence ignoring.
> 
> Looks like you have some problem.

You don't know Jerry too well...

-- 
Matthew Donadio (m.p.donadio@ieee.org)

                      STANDARDIZED BONEHEAD REPLY FORM
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Peter Brackett <ab4bc@ix.netcom.com> wrote:

>> What is Viterbi's claim to fame - only the Viterbi algorithm ?
>>
>> Has  he invented any  other theorem or circuit or algorithm ?
> 
> Andrew Viterbi has made many original contributions to communications
> technology.
[...]
> 
> The so-called "Viterbi Algorithm" which is a maximum likelihood sequence
> estimation
> algorthim is nothing more nor less than an "exhaustive search" of all
> possible lattice
> paths seeking the one with the maximum likelihood!  Not very subtle!
> Exhaustive
> search is the "dumbest" of all possible optimization methods.  This
> technique of
> "exhaustive search" of all possible solutions until the optimum is found is
> often called
> "dynamic programming".  The so-called Viterbi Algorithm is nothing more nor
> less
> than the "dynamic programming" or "exhaustive search" algorithm.
[...]

Hi,

I'm currently suffering under it's complexity of O(T*N^2) (T=length of
observation/state sequece, N=number of states in HMM).

Does anybody know of good heuristics when working with a left-right-HMM (so
called "Bakis-HMM")?
-- 
Michael
  Weitzel

> The example with Einstein is a bad one since the Nobel prize has an
> advancement of technology requirement which is much more appropriate to
his
> explanation of the photoelectric effect, which is by the way what he won
the
> Nobel prize for. While Lorentz and Poincare did a lot for the math behind
> relativity, Einstein took it much furthur than anyone else at the time and
> thusly did a lot of original work. But there was no application to
> technology (then) so there was no prize. So I wouldn't say he got the
prize
> for a lessor work, but rather for a more applicable to the rules of the
> prize committee work.

In fact, the photoelectric effect work was a direct precursor to quantum
mechanics. So although it isn't what Einstein is most famous for,
I don't think it is less important in any way.

Y(J)S

> > For the unit of frequency, it would have been better to honor Steinmetz,
> > the proponent of AC power distribution (Edison championed DC). Then we
> > could have used his initials and achieved continuity. His full name, of
> > course, was Charles Proteus Steinmetz.

That's a great one!

However, the real champion of AC when Edison was out pushing DC
was Nikola Tesla. And all he ever got was an infrequently used
unit of magnetic field, and his initials were blasphemed with a non-Unix
server operating system.

Y(J)S

"Jonathan Y Stein" <author@dspcsp.com> wrote in message
news:bhb4su$590$1@news2.netvision.net.il...
>
> However, the real champion of AC when Edison was out pushing DC
> was Nikola Tesla. And all he ever got was an infrequently used
> unit of magnetic field, and his initials were blasphemed with a non-Unix
> server operating system.

Jonathan,
I don't know about the OS, but the unit, tesla, is hardly infrequently used!
When one first encounters magnetic flux density in first year physics, he
learns this unit. I know that I assign many problems that use teslas. A
common equivalent is webers per square meter. Some old schoolers may use
gauss for field strength, but the standard unit for field strength is tesla.
(1 tesla = 10000 gauss). A gauss is convenient when describing the Earth's
field near the surface. The density there is about 1/2 gauss.

E-Mag used to be taught using gaussian units, but the paradigm is to now use
rationalized MKSA units, so the tesla has become the natural one.

Clay

p.s.   Trivia question??? What is the only (known to someone with one or two
year's worth of physics/ e-mag)  unit named for an American (non-immigrant)
scientist?


>
> Y(J)S
>
>
>
>
>

"Clay S. Turner" wrote:
> 
> "Jonathan Y Stein" <author@dspcsp.com> wrote in message
> news:bhb4su$590$1@news2.netvision.net.il...
> >
> > However, the real champion of AC when Edison was out pushing DC
> > was Nikola Tesla. And all he ever got was an infrequently used
> > unit of magnetic field, and his initials were blasphemed with a non-Unix
> > server operating system.
> 
> Jonathan,
> I don't know about the OS, but the unit, tesla, is hardly infrequently used!
> When one first encounters magnetic flux density in first year physics, he
> learns this unit. I know that I assign many problems that use teslas. A
> common equivalent is webers per square meter. Some old schoolers may use
> gauss for field strength, but the standard unit for field strength is tesla.
> (1 tesla = 10000 gauss). A gauss is convenient when describing the Earth's
> field near the surface. The density there is about 1/2 gauss.
> 
> E-Mag used to be taught using gaussian units, but the paradigm is to now use
> rationalized MKSA units, so the tesla has become the natural one.
> 
> Clay
> 
> p.s.   Trivia question??? What is the only (known to someone with one or two
> year's worth of physics/ e-mag)  unit named for an American (non-immigrant)
> scientist?

Watt do you mean?

-- 
Jim Thomas            Principal Applications Engineer  Bittware, Inc
jthomas@bittware.com  http://www.bittware.com          (703) 779-7770
There's a fine line between clever and stupid

Jim Thomas wrote:
> "Clay S. Turner" wrote:
> 
>>"Jonathan Y Stein" <author@dspcsp.com> wrote in message
>>news:bhb4su$590$1@news2.netvision.net.il...
>>
>>>However, the real champion of AC when Edison was out pushing DC
>>>was Nikola Tesla. And all he ever got was an infrequently used
>>>unit of magnetic field, and his initials were blasphemed with a non-Unix
>>>server operating system.
>>
>>Jonathan,
>>I don't know about the OS, but the unit, tesla, is hardly infrequently used!
>>When one first encounters magnetic flux density in first year physics, he
>>learns this unit. I know that I assign many problems that use teslas. A
>>common equivalent is webers per square meter. Some old schoolers may use
>>gauss for field strength, but the standard unit for field strength is tesla.
>>(1 tesla = 10000 gauss). A gauss is convenient when describing the Earth's
>>field near the surface. The density there is about 1/2 gauss.
>>
>>E-Mag used to be taught using gaussian units, but the paradigm is to now use
>>rationalized MKSA units, so the tesla has become the natural one.
>>
>>Clay
>>
>>p.s.   Trivia question??? What is the only (known to someone with one or two
>>year's worth of physics/ e-mag)  unit named for an American (non-immigrant)
>>scientist?
> 
> 
> Watt do you mean?
> 
Henry?

"Jim Thomas" <jthomas@bittware.com> wrote in message
news:3F391E41.87031FE6@bittware.com...

> > p.s.   Trivia question??? What is the only (known to someone with one or
two
> > year's worth of physics/ e-mag)  unit named for an American
(non-immigrant)
> > scientist?
>
> Watt do you mean?

James Watt was Scottish

see for details:

http://www.ideafinder.com/history/inventors/watt.htm

>
> -- 
> Jim Thomas            Principal Applications Engineer  Bittware, Inc
> jthomas@bittware.com  http://www.bittware.com          (703) 779-7770
> There's a fine line between clever and stupid

"Stan Pawlukiewicz" <stanp@nospam_mitre.org> wrote in message
news:bhb8am$olt$1@newslocal.mitre.org...
> >
> Henry?
>


Stan,

Yes - you get the prize. I don't know what it is, but you get it.

I remember seeing some of his magnets at the Smithsonian. Pretty impressive.

See

http://www.si.edu/archives/ihd/jhp/

for more details on this man

Clay

Clay S. Turner <physicsNOOOOSPPPPAMMMM@bellsouth.net> wrote:


> p.s.   Trivia question??? What is the only (known to someone with one or two
> year's worth of physics/ e-mag)  unit named for an American (non-immigrant)
> scientist?

Henry.

						Didier

-- 
Didier A Depireux         ddepi001@umaryland.edu  didier@isr.umd.edu
685 W.Baltimore Str      http://neurobiology.umaryland.edu/depireux.htm
Anatomy and Neurobiology                      Phone: 410-706-1272 (off)
University of Maryland                                      -1273 (lab)
Baltimore MD 21201 USA                             Fax: 1-410-706-2512

kbc32@yahoo.com (kbc) writes:

> Do i look like an idiot to think that ieee conducts an yearly auction
> to give away these designations ??

Yes.

Ciao,

Peter K.

-- 
Peter J. Kootsookos

"Na, na na na na na na, na na na na"
- 'Hey Jude', Lennon/McCartney

Jerry Avins <jya@ieee.org> wrote in message news:<3F381962.74B4704D@ieee.org>...
> Steve Underwood wrote:
> > 
> > The less neat something really is, is the more it needs a good name.
> > 
> > When someone says "how does your error handling work" do you really want
> > to say "the receiver gropes around in the dark, trying endless
> > possibilities, until it stumbles on its best guess at the actual
> > transmitted data". Isn't "we use Viterbi techniques to evaluate the
> > maximum likelihood sequence" better? Better still "we use Viterbi
> > techniques to evaulate the MLS" avoids a phrase that still sounds like
> > vague guessing.
> > 
> > Regards
> > Steve
> > 
> > Peter Brackett wrote:
> > >
> > > OTOH... any literature search will uncover the many unique contributions of
> > > Andrew Viterbi to communications sciences!  It's just that the only one
> > > named
> > > for him is not that important and was not even discovered or invented by
> > > him!
> 
> I don't know about the last improvement. Whenever I see "MLS", I think
> "PMS". I don't know why.
> 
> Jerry

Perhaps because "MLS" puts an end to any discussion almost as efficiently 
as "PMS" does...

Rune

On Mon, 11 Aug 2003 23:24:44 -0700, kbc wrote:
> Do i look like an idiot to think that ieee conducts an yearly auction
> to give away these designations ??

Your question about the purpose of the newsgroup gave exactly that
impression.

-- 
Andrew

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