Convolutional coding and Viterbi decoding may increase the occupied bandwidth
but they also decrease the amount of power required to communicate. In some
cases, like trellis-coded modulation, the bandwidth stays the same even though
the power required decreases by a factor of 2-4. Spread spectrum increases the
occupied bandwidth without the decrease in power.
73,
John
KD6OZH
----- Original Message -----
From: W2XJ
To: digitalradio@yahoogroups.com
Sent: Wednesday, February 24, 2010 01:24 UTC
Subject: Re: [digitalradio] Consensus? Is ROS Legal in US?`
I have a different take on this. There are a number of modes that uses
vertebrae coding which could be mis-described as spread spectrum by some. The
problem with part 97 is that it tries to be as broad as possible where
technical parameters are concerned. In this case it causes things to be vague.
There are many things that can be described as spread spectrum that are not by
definition in part 97. FM would be one of them. Anytime information is
transmitted in a wider bandwidth than necessary it could be described as spread
spectrum. This would include some low noise modes. The problem is that we
petitioned the FCC to loosen SS rules and the more vague those rules are made
the more open to debate they are.
The worst that can happen under the rules if one would be operating ROS in
the phone segment would be an order to cease such operation if the comish so
ordered.
------------------------------------------------------------------------------
From: KH6TY <kh...@comcast.net>
Reply-To: <digitalradio@yahoogroups.com>
Date: Tue, 23 Feb 2010 19:53:53 -0500
To: <digitalradio@yahoogroups.com>
Subject: Re: [digitalradio] Consensus? Is ROS Legal in US?`
I am for whatever will succeed, but do not underestimate how difficult it is
to convincingly reverse oneself after first originally being so convincing.
For myself, even from the beginning, I could not understand how the spreading
was accomplished by a code that everyone else automatically had, but that was
the claim, so I accepted it. Perhaps there is no spreading code independent of
the data, but if so, it must now be proven thus, and not just claimed in what
might be seen as an attempt to have something approved that has already been
disapproved.
Just because I might possess the necessary technical skills does not mean I
can individually overrule the FCC with my actions. Even opposing technical
experts are called by both parties in a legal argument, and the "judge" to
decide who is correct in this case is the FCC, which has already issued an
opinion, even if it may be wrong if given new information, but just "saying it
is so does not make it so". I believe some concrete proof is required now, and
maybe your spectrum analyzer display can be part of such proof.
Other's opinions may vary...
73 - Skip KH6TY
W2XJ wrote:
Skip
You are over thinking this. The FCC said as they always do that you as a
licensee must possess the technical skill to evaluate whether or not a
particular mode meets the rules. On Jose's part a better technical description
and some clarification would be very helpful to this end. I think just looking
at the output on a spectrum analyzer would also be quite revealing.
----------------------------------------------------------------------------
From: KH6TY <kh...@comcast.net>
Reply-To: <digitalradio@yahoogroups.com>
Date: Tue, 23 Feb 2010 19:03:06 -0500
To: <digitalradio@yahoogroups.com>
Subject: Re: [digitalradio] Consensus? Is ROS Legal in US?`
Jose,
I am only trying to suggest whatever ideas I can to get ROS declared to be
legal. You have made such a strong case for FHSS already, that only "saying"
you were mistaken probably will not convince the FCC. They will assume you are
only changing the description so ROS appears to be legal and will demand proof
that it is not FHSS to change their minds. This is only my personal, unbiased,
opinion, as I would like very much for you to succeed.
Essentially, you must PROVE that, spreading is NOT accomplished by means of
a spreading signal, often called a code signal, which is independent of the
data. How do you do that without disclosing the code? At this point, I doubt
that the FCC will believe mere words, because there is so much pressure to
allow ROS in HF in this country.
Keep in mind the mess that Toyota finds itself by previously denying there
is any substantial problem with unattended acceleration or braking of their
cars. That may still prove to be true (i.e. not "substantial"), but the
government here is now demanding that Toyota SHOW proof that there is no
problem, and not merely saying there is not. This is currently a very hot topic
with the government and Congress and on the minds of everyone. So I assume
likewise that PROOF will have to be SHOWN that there is no spreading signal
used in ROS. Mere words will probably not be enough, and there is probably only
ONE chance to succeed, so you need to be successful the first time. If you
decide to only change the description and nothing further, I sincerely hope I
am wrong, and I could well be. But, that is your decision, not mine.
If you need to protect your invention, then just fully document and witness
it, or do whatever is necessary in your country and others, and be free to do
whatever is required to win this battle.
Good luck!
73 - Skip KH6TY
jose alberto nieto ros wrote:
Hi, KH6.
I only i am going to describe in a technicals article how run the mode.
If FCC want the code they will have to buy it me, that is obvious.
--------------------------------------------------------------------------
De: KH6TY <kh...@comcast.net>
Para: digitalradio@yahoogroups.com
Enviado: mié,24 febrero, 2010 00:31
Asunto: Re: [digitalradio] Consensus? Is ROS Legal in US?`
Jose,
"
You will have to disclose the algorithm that determines the spreading on
ROS (independent of the data), or bandwidth expansion, if that is actually
used. You will have to convince technical people that will show your new
description to our FCC that your original description was wrong and prove it by
revealing your code. I think this is the only way to get the FCC opinion
reversed. You now have a difficult task before you, but I wish you success, as
ROS is a really fun mode.
73 - Skip KH6TY
jose alberto nieto ros wrote:
Is legal because ROS is a FSK modulation.
------------------------------------------------------------------------
De: ocypret <n5...@arrl.net> <mailto:n5...@arrl.net>
Para: digitalradio@ yahoogroups. com
Enviado: mar,23 febrero, 2010 21:26
Asunto: [digitalradio] Consensus? Is ROS Legal in US?`
So what's the consensus, is ROS legal in the US or not?
