Bonnie, Your remarks about this person, and I don't know who it is, are not very convincing. Your award winning design apparently had to do with co-channel interference. This is not the same as on-channel interference that increases the total noise level, which is what BPL interference is. On-channel interference requires different techniques to solve than co-channel interference.
Better receivers (roofing filters, increased IM3 capability, etc.) are all answers to co-channel interference, along with higher transmitting power. On-channel interference is a whole different animal. It doesn't do any good to have a receiver with an MDS of -140 dBm, an IM3 @ 2 Khz of 120 dB, and brickwall filtering of 3 kHz when the noise floor is -80 dBm due to BPL and the digital signal you want to copy is at -120 dBm. The only answer to this is higher transmitter power! Perhaps you can provide some concrete data on how a digital signal or digital processing techniques can eliminate the difference in signal level (i.e. signal to noise ratio) between what you're trying to receive and the noise floor at the receiver's antenna? Jim WA0LYK --- In [email protected], "expeditionradio" <[EMAIL PROTECTED]> wrote: > > > Bob N4HY wrote: > > I recently had a general manager of a large amateur radio > > organization tell me that if I made it possible to communicate > > through BPL or in any way mitigated BPL through DSP techniques, > > I would begin to sing soprano and the GM did not mean falsetto. > > Hi Bob, > > That sort of threat would not be very effective against me :) > > When I originally proposed this subject, digital communications for > hams to communicate through BPL interference, some of the higher ups > in that organization were none too happy with me, either. > > This led to a curious interaction with the guy spearheading their BPL > interference testing. He told me that what I was talking about was "an > engineering impossibility" and "I didn't know what I was talking about". > > At one of my companies, I designed communication systems that solved > much more severe co-channel interference problems than BPL. One of > those products, based upon these same principles, received a major > technology design award several years ago. I sent him one of the > product brochures. > > I have not heard from him since :) > > Presently, BPL has literally put some ham operators off the air. > Other semiconductor-based EMI sources are having similar effects. > Restoring these operators to being on the air again is good for ham > radio. It might also put the BPL systems on notice, since they could > no longer rely upon their interference effectively silencing hams to > alleviate their own weakness of EMI susceptibility to RF ingress. > > Bonnie KQ6XA > Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) <*> To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
