In message <20120315152620.8347488e049854218aed4...@kinali.ch>, Attila Kinali w rites:
>> Do you need 16 bits or can you get by with a 12 bit ADC? In general: The more the merrier, for a digital dude like me, having more bits is easier than getting AGC working correctly :-) >> Have you considered using an FPGA for signal processing? It seems > you need a fairly serious CPU to handle that much data. I have considered FPGA, DSP would probably be more suitable, but if I can do it in an ARM with C/Assy code, I prefer that. >I think Poul-Henning is refering to his AducLoran receiver, That's one of the few experiements I bothered to document, I've been doing similar stuff with DCF77 phase-code etc. As long as you're after time/freq, you can use very deep averaging which only takes a few instructions per sample, so for instance the 42MHz Aduc7026 chip copes nicely with a single Loran-C signal. I think I could squeeze a Loran-C navigation solution into it, if I wanted to and as long as we're not talking too high speeds (again allowing deep averaging) but I have not bothered. A modern PC has a lot of computing power for stuff like this, and is great for prototyping code, before dumping into a smaller chip. That's how I found out that the circular-buffer averaging comb-filter is a much better and stronger signal discriminator than almost anything else you can come up with, for frequency/phase reception. See for instance: http://phk.freebsd.dk/loran-c/CW/ -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.