It is generally accepted that 10 times bandwidth is the minimum necessary to achieve enough processing gain to make the use of SS worthwhile.
On 7/13/10 3:55 PM, "J. Moen" <[email protected]> wrote: > > > > > > > There's the generally accepted definition of SS, quoted below and referring to > bandwidths greatly exceeding what's necessary, and then there's the way the > FCC regs are written, which do not refer to that definition. > > I think just about everyone, or maybe absolutely everyone who cares about the > FCC regs, thinks in this case they are inappropriate, but the fact is, they do > not allow for narrow-band SS, even though it would cause no real harm. > > The regs should be changed, but until they are, we in the US can not use SS > below 220, or we can move to another country, or we can violate the regs, > and/or we can campaign to change them. But saying you don't agree with a law > so you don't have to follow it is not the right way. > > Jim - K6JM > >> >> ----- Original Message ----- >> >> From: [email protected] >> >> To: [email protected] >> >> Sent: Tuesday, July 13, 2010 11:23 AM >> >> Subject: Re: [digitalradio] Re: Random data vs Spread Spectrum >> >> >> Hi Alan, >> >> Why did you wait so long with contributing here? >> Please explain. >> >> ++ In Feb of this year I quoted from the ARRL's Spread Spectrum Source book >> page 5-2 ++ >> >> " Spread Spectrum Fundamentals " >> >> SS systems employ radio frequency bandwidths that greatly exceed the >> bandwidth necessary >> to convey the intelligence. >> >> Bandwidths for SS systems generally run from 10 to 100 times the information >> rate. >> >> etc etc. >> >> I got shouted out of the Group by addressing the use of ROS in the US by the >> experts on >> SS. >> >> 73 Rein W6SZ > > > >
