Perhaps GNU Radio? On Monday, January 14, 2019, David Van Horn < david.vanhorn@backcountryaccess.com> wrote: > Is there a package available that will let me experiment with various DSP > functions on the PC platform while I search for a microcontroller > implementation that fits my needs? > Ideally I would be able to create files (WAV?) with noise sources, signal > sources, impulse noise etc mixing them into a file and controlling their > amplitudes individually, even listening to it to compare to what I hear o= n > air, then feeding them to the algorithms, showing waterfalls.. > > I really would prefer to get this in a single package, or maybe two parts= , > so I can concentrate on solving the problem. > > -----Original Message----- > From: piclist-bounces@mit.edu On Behalf Of > David Van Horn > Sent: Thursday, January 10, 2019 8:52 AM > To: Microcontroller discussion list - Public. > Subject: RE: [EE] DSP algorithms for very narrow band applications > > I've been interested in the 630 meter band between 472 and 479 kHz for > some time, I would like to see just how good a receiver I can make. > 5W EIRP maximum, and contacts are already being made over huge distances. > > > -----Original Message----- > From: piclist-bounces@mit.edu On Behalf Of > Harold Hallikainen > Sent: Wednesday, January 9, 2019 2:38 PM > To: Microcontroller discussion list - Public. > Subject: Re: [EE] DSP algorithms for very narrow band applications > > Sounds like an interesting project! I have very little DSP experience > other than telling a DSP engineer what I want, and the code magically > appears. But http://www.earlevel.com/main/2013/10/13/biquad-calculator-v2= / > has proved useful. I'm currently using a biquad as a CW filter for > reception by ear. Picking up signals below the noise level is interesting= .. > This, of course, is what FT8 and similar weak signal techniques do using > multi-frequency shift keying. > > Are you also looking at machine decoding of the CW? I note that there is = a > CW decoder in KiwiSDR, but it is very error prone with noise and fading. > > I am, as a background project, looking at using SOMETHING for amateur > radio applications. My transceiver has an RS485 control bus along with a > balanced audio bus and PTT. I'm thinking of maybe using an old netbook to > control it, stream audio, etc., OR using a PIC32 (maybe MZ) to do the sam= e. > I'm MUCH more familiar with PIC32 software, including streaming audio (PC= M > and ADPCM) than I am familiar with linux talking to hardware like a USB > audio interface, USB RS485 interface, etc.). So, still playing around wit= h > ideas. > > I look forward to hearing other comments you get. > > Harold > http://w6iwi.org > > > I had posted a couple weeks ago and I guess it fell in the bit bucket. > > > > I'm looking for info on DFT or similar approaches to detect very weak > > CW signals buried in noise. > > I'm only interested in a 200Hz window, and I can control where it > > falls frequency wise, between 150Hz (center) and several kHz. > > I need as much frequency detail as possible, sub 1Hz definitely, but > > the "dot" is pretty short. At 20WPM that works out to well below. > > https://www.w8ji.com/cw_bandwidth_described.htm > > > > This will get implemented on an AVR or similar, with input from the > > on-board ADC. > > > > I expect I will need a rather long array of samples, but I am starting > > to think of a circular buffer there and sending chunks of to the DSP > process. > > > > I have looked in Smith's DSP book, but I haven't found what I'm > > looking for. > > > > -- > > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > > View/change your membership options at > > http://mailman.mit.edu/mailman/listinfo/piclist > > > > > -- > FCC Rules Updated Daily at http://www.hallikainen.com Not sent from an > iPhone. > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at http://mailman.mit.edu/ > mailman/listinfo/piclist > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at http://mailman.mit.edu/ > mailman/listinfo/piclist > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 Jason White --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .