Dear all, We are looking for a robust FSK demodulator and framer solution for an SDR application (decoding of simultaneous narrow channels at some kbps each from a wider baseband stream) : channel filtering, center frequency tracking, demodulation, bit-level timing recovery, synchronisation frame detection, etc. Could be either DSP or FPGA based. Any "off the shelf" industrial-level IP bricks, open source projects or applications notes that could avoid us to develop everything from scratch ? Thanks for your help ! Yours, Robert Lacoste www.alciom.com
Robust FSK demodulator ?
Started by ●February 23, 2012
Reply by ●February 23, 20122012-02-23
On Thu, 23 Feb 2012 08:31:45 +0100, Robert Lacoste wrote:> Dear all, > > We are looking for a robust FSK demodulator and framer solution for an > SDR application (decoding of simultaneous narrow channels at some kbps > each from a wider baseband stream) : channel filtering, center frequency > tracking, demodulation, bit-level timing recovery, synchronisation frame > detection, etc. Could be either DSP or FPGA based. Any "off the shelf" > industrial-level IP bricks, open source projects or applications notes > that could avoid us to develop everything from scratch ?I could be wrong, but this feels like the sort of thing (like PID controllers) where, if you're good enough to adapt someone else's work, the core functionality is really easy to whomp up from scratch. Furthermore (again like PID controllers), it seems that the effort to adapt someone else's IP to your particular situation may well eclipse the effort to just embed the core functionality into your custom solution. Things like how the data is coded coming in, whether the sampling rate is (or can be) synchronized to the data, what the sampling rate is as a proportion of the baud rate (although here it's undoubtedly high), etc., are all variables that make a good efficient generic implementation hard to do. The exception would be if it's for some specific radio service, that may be popular enough to justify a large, integrated block of IP that has had effort poured into it to make it truly portable, and not just a good example to follow. -- My liberal friends think I'm a conservative kook. My conservative friends think I'm a liberal kook. Why am I not happy that they have found common ground? Tim Wescott, Communications, Control, Circuits & Software http://www.wescottdesign.com
Reply by ●February 27, 20122012-02-27
"Tim Wescott" <tim@seemywebsite.com> a �crit dans le message de news: lumdncw2Wo4a6NvSnZ2dnUVZ_qOdnZ2d@web-ster.com...> On Thu, 23 Feb 2012 08:31:45 +0100, Robert Lacoste wrote: > >> Dear all, >> >> We are looking for a robust FSK demodulator and framer solution for an >> SDR application (decoding of simultaneous narrow channels at some kbps >> each from a wider baseband stream) : channel filtering, center frequency >> tracking, demodulation, bit-level timing recovery, synchronisation frame >> detection, etc. Could be either DSP or FPGA based. Any "off the shelf" >> industrial-level IP bricks, open source projects or applications notes >> that could avoid us to develop everything from scratch ? > > I could be wrong, but this feels like the sort of thing (like PID > controllers) where, if you're good enough to adapt someone else's work, > the core functionality is really easy to whomp up from scratch. > Furthermore (again like PID controllers), it seems that the effort to > adapt someone else's IP to your particular situation may well eclipse the > effort to just embed the core functionality into your custom solution. > > Things like how the data is coded coming in, whether the sampling rate is > (or can be) synchronized to the data, what the sampling rate is as a > proportion of the baud rate (although here it's undoubtedly high), etc., > are all variables that make a good efficient generic implementation hard > to do. > > The exception would be if it's for some specific radio service, that may > be popular enough to justify a large, integrated block of IP that has had > effort poured into it to make it truly portable, and not just a good > example to follow. > > -- > My liberal friends think I'm a conservative kook. > My conservative friends think I'm a liberal kook. > Why am I not happy that they have found common ground? > > Tim Wescott, Communications, Control, Circuits & Software > http://www.wescottdesign.comThanks Tim, that was unfortunately also my feeling, but I prefered to check if there are clever people who have developped very clever and adaptable IPs before starting to code... We will follow your advice, probably looking at GNUradio to grab goog ideas.. Friendly yours, Robert
