> jose alberto nieto ros wrote:
> I propose to moderator you will be banned if you continue
saying stupid things in this group.
Moderated for stupidity? Now that will be a first!
Good luck with trying to fool the FCC. Spectral analysis suggests ROS
really is FHSS, no matter what you now try to claim.
This picture does not lie: http://home.comcast.net/~hteller/SPECTRUM.JPG
Too bad - ROS is a fun mode and I cannot use it in USA except on UHF.
I have only tried to help find a way for US hams to use ROS. It will be
an honor to be banned for my stupidity! :-) Please go ahead as you wish.
73, Skip KH6TY SK
jose alberto nieto ros wrote:
My friend, one thing is what i wrote, and other different is what ROS is.
If recommend you waste your time in doing something by Ham Radio,
instead of criticism ROS.
I propose to moderator you will be banned if you continue
saying stupid things in this group.
------------------------------------------------------------------------
*De:* KH6TY <kh...@comcast.net>
*Para:* digitalradio@yahoogroups.com
*Enviado:* vie,26 febrero, 2010 13:18
*Asunto:* Re: [digitalradio] ROS carrier pattern when idle
> If MFSK16 was randomized would it magically become spread-spectrum?
Alan, sorry I forgot to reply to this question.
The answer is yes, but only if the following three conditions are ALL
met (from the ROS documentation) :
1. The signal occupies a bandwidth much in excess of the minimum
bandwidth necessary to send the information.
2. Spreading is accomplished by means of a spreading signal, often
called a code signal, which is independent of the data.
3. At the receiver, despreading (recovering the original data) is
accomplished by the correlation of the received spread signal with a
synchronized replica of the spreading signal used to spread the
information.
Standard modulation schemes as frequency modulation and pulse code
modulation also spread the spectrum of an information signal, but they
do not qualify as spread-spectrum systems since they do not satisfy
all the conditions outlined above.
Looking at the comparison between ROS and MFSK16, http://home.
comcast.net/ ~hteller/ SPECTRUM. JPG, it is easy to see that MFSK16 is
not FHSS, but ROS definitely is.
Another thing that a petition should include is a requirement that ROS
only be used BELOW the phone segments and ABOVE the narrowband data
segments. On 20m, that means only between 14.1 and 14.225, because ROS
is so wide.
BTW, this same issue came up during the "regulation by bandwidth"
debate when the ARRL HSMM (High Speed MultiMedia) proponents wanted to
allow wideband, short timespan, signals everywhere with the argument
that they last such a short time on any given frequency that they do
not interfere, but the fallacy to that argument is that when you get a
multitude of HSMM signals on at the same time, all together they can
ruin communication for narrow modes, like PSK31.
The other problem is that SHARING of frequencies requires that users
of one mode be able to communicate with users of another mode in the
same space so QRL or QSY can be used. It was realized that only CW
used by both parties would make this possible. ROS does not work well
in a crowded environment or with wideband QRM, so it must find a home
relatively clear of other mode QRM. This is just another job the FCC
must do in order to be sure a new mode does not create chaos. It has
already been shown that leaving that up just to hams does not work,
and the strongest try to take over the frequencies.
upper
73 - Skip KH6TY
Alan Barrow wrote:
If MFSK16 was randomized would it magically become spread-spectrum?
