Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110
It seems that the MIL-STD/STANAG modems frequently use a variety of wavefoms depending upon the speed. An example would be the STANAG 4539 suite of standardized waveforms. They are not all the same waveforms. Starting at 75 bps data modes it uses Walsh modulation and switches to BPSK at 150 bps, QPSK at 1200, 8-PSK at 2400 data and voice and then for faster voice up to 64-QAM at 12800 bps. This suggests that a highly adaptive modem may not necessarily need only one modulation type. STANAG 4285 is one exception and uses only PSK waveforms from 75 to 3600 bps. It is not easy to find much on the baud rate but I did find that the STANAG 4529 modem which is intended for 1240 Hz wide bandwidths (marine ship to shore) use 1200 symbols per second. This is what I have considered to be the baud rate. This is a narrower mode thus the slower baud rate. The one thing that comes across from comparing speeds vs. S/N is that there are really are no fast modems that can go down below zero dB. In fact, to get data rates of 1200 bps it is often around +10 dB. A lot of this information came from a web site from Rapid M a company in South Africa. 73, Rick, KV9U John Champa wrote: Rick, Now that is some interesting research! More please. Thanks, John K8OCL Original Message Follows From: kv9u [EMAIL PROTECTED] Reply-To: digitalradio@yahoogroups.com To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110 Date: Fri, 16 Mar 2007 17:00:21 -0500 I was able to find some interesting data on poor channel performance of the 110A modem from one company: http://www.etools.de/software/telekommunikation/komponenten/milstd188110a.htm Depending upon the BER you can tolerate, it appears that the 2400 bps speed can only handle around +10 to +14 S/N dB. The slower bps rates can work to around zero S/N. Te 150 bps shows something around -1 to -4. Another interesting specification is the the multipath tolerance. They claim 6 msec at 2400 bps, 8 ms from 150 to 1200 bps, and 12 mec at 75 baud. That seems to have good ability to cope with ISI. Now these are the bps rates. Isn't the baud rate the same 2400 baud, all the time for this modem, contrary to what Bonnie claims? 73, Rick, KV9U
Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110
Well, MIL-STD-188-110A uses a single phase shifted tone , I guess that made it even more non-intuitive ? The difference between packet and this MIL-STD is just huge. Interleaver to fight fade and QRM, equalization to benefit from multipath and the list could just go on and on. 300 baud packet is a joke. 73 de Per, sm0rwo --- kv9u [EMAIL PROTECTED] wrote: It still seems a bit non-intuitive that using a 2400 baud rate with two tones can work well and yet 300 baud packet hardly works well at all. There is something that I am missing here. 73, Rick, KV9U expeditionradio wrote: Yes. MIL STD 188-110 is in PCALE software (along with standard ALE). Operators have been using -110 (outside USA) for data files. I was using the RFSM2400 while I was in Hong Kong, China. It is a good system, and the modified narrow version takes no more bandwidth than some other digital modes or SSB voice. As you know, USA has an arbitrary 300 symbol/second limit in the USA Data Subbands. But there is no such 300 baud limit in the phone and image subbands, so some of us in USA have used -110 to send image files. It does that quite well, but the real forte of -110 is data FTP and email. Wow... 2007... a shame that USA hams are living under those antiquated FCC rules made for the previous century's technology. USA hams still sit rotting in the FCC's technology jail. The rest of the world's hams can use RFSM2400 freely for data or mail. Bonnie KQ6XA No need to miss a message. Get email on-the-go with Yahoo! Mail for Mobile. Get started. http://mobile.yahoo.com/mail
Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110
If the 110A works this well at 2400 baud, what would happen with slower speeds? From what I understand, it does require a good signal to get through, perhaps comparable to the WinDRM software at maybe +10 S/N dB or maybe a bit below that? 73, Rick, KV9U Per wrote: Well, MIL-STD-188-110A uses a single phase shifted tone , I guess that made it even more non-intuitive ? The difference between packet and this MIL-STD is just huge. Interleaver to fight fade and QRM, equalization to benefit from multipath and the list could just go on and on. 300 baud packet is a joke. 73 de Per, sm0rwo
Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110
Poor Bonnie! We are hitting you from both directions: --some want better weak signal performance at the cost of speed (~HF) --some want more speed at the cost of signal performance (~10M VHF) Original Message Follows From: kv9u [EMAIL PROTECTED] Reply-To: digitalradio@yahoogroups.com To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110 Date: Fri, 16 Mar 2007 09:32:30 -0500 If the 110A works this well at 2400 baud, what would happen with slower speeds? From what I understand, it does require a good signal to get through, perhaps comparable to the WinDRM software at maybe +10 S/N dB or maybe a bit below that? 73, Rick, KV9U Per wrote: Well, MIL-STD-188-110A uses a single phase shifted tone , I guess that made it even more non-intuitive ? The difference between packet and this MIL-STD is just huge. Interleaver to fight fade and QRM, equalization to benefit from multipath and the list could just go on and on. 300 baud packet is a joke. 73 de Per, sm0rwo
[digitalradio] Re: RSM2400 / MIL-STD-188-110
--- In digitalradio@yahoogroups.com, kv9u [EMAIL PROTECTED] wrote: If the 110A works this well at 2400 baud, what would happen with slower speeds? From what I understand, it does require a good signal to get through, perhaps comparable to the WinDRM software at maybe +10 S/N dB or maybe a bit below that? 73, Rick, KV9U Hi Rick, Your understanding is not correct. The lower baud rates of the 188-110 PSK system work in *negative SNR*. That is much farther down into the noise than DRM. May I suggest you download RFSM2400 and receive some of the signals on the air. This might give you a better feel for it. Bonnie KQ6XA .
Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110
The slower speeds are better when the condx is worse, 75 bps and long interleave gets through just about anything. I have not really had to use it at that speed , 1200 bps gets through nicely too. I don't know how good the implementation in RFSM is, my experience is based upon years of daily use of the Harris RF-5710(A) modem so I need to use RFSM for a while to be able to say. Trouble is RFSM just doesn't play very well on linux, it hangs at times. 73 de Per, sm0rwo --- kv9u [EMAIL PROTECTED] wrote: If the 110A works this well at 2400 baud, what would happen with slower speeds? From what I understand, it does require a good signal to get through, perhaps comparable to the WinDRM software at maybe +10 S/N dB or maybe a bit below that? 73, Rick, KV9U Per wrote: Well, MIL-STD-188-110A uses a single phase shifted tone , I guess that made it even more non-intuitive ? The difference between packet and this MIL-STD is just huge. Interleaver to fight fade and QRM, equalization to benefit from multipath and the list could just go on and on. 300 baud packet is a joke. 73 de Per, sm0rwo Expecting? Get great news right away with email Auto-Check. Try the Yahoo! Mail Beta. http://advision.webevents.yahoo.com/mailbeta/newmail_tools.html
RE: [digitalradio] Re: RSM2400 / MIL-STD-188-110
What if an individual wants high speed AND good low signal leveel throughput? I think the first thing is that individuals need to decide what USER throughput they want in CPS or WPM or PPM and then at what the lowerest SNR they expect the mode to provide 95% copy (or some percent of perfect). As Dave AA^YQ has said, there may not be one mode that works for all bands and under all scenerios...so more than one mode may be called for. IMHO a chat mode need not provide for more then 60 or so WPM but you might want it to provide 95% copy at a -15 dB SNR and you don't care what the bandwidth is as long as its small. On the other hand you may to esnt ASCII and binary files from point to point with a throughput so that a 40 Kbps file can be sent in 5 milutes or less and the mode must give 98% copy at a -10 dB SNR and if it shold have an ARQ feature that can be turned on to give you 100% copy for binary. You might wind up with a suite of modes call from a menu such as attached. Walt/K5YFW -Original Message- From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of John Champa Sent: Friday, March 16, 2007 2:57 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110 Poor Bonnie! We are hitting you from both directions: --some want better weak signal performance at the cost of speed (~HF) --some want more speed at the cost of signal performance (~10M VHF) Original Message Follows From: kv9u [EMAIL PROTECTED] Reply-To: digitalradio@yahoogroups.com To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110 Date: Fri, 16 Mar 2007 09:32:30 -0500 If the 110A works this well at 2400 baud, what would happen with slower speeds? From what I understand, it does require a good signal to get through, perhaps comparable to the WinDRM software at maybe +10 S/N dB or maybe a bit below that? 73, Rick, KV9U Per wrote: Well, MIL-STD-188-110A uses a single phase shifted tone , I guess that made it even more non-intuitive ? The difference between packet and this MIL-STD is just huge. Interleaver to fight fade and QRM, equalization to benefit from multipath and the list could just go on and on. 300 baud packet is a joke. 73 de Per, sm0rwo Yahoo! Groups Sponsor ~-- Great things are happening at Yahoo! Groups. See the new email design. http://us.click.yahoo.com/lOt0.A/hOaOAA/yQLSAA/ELTolB/TM ~- Announce your digital presence via our DX Cluster telnet://cluster.dynalias.org Our other groups: http://groups.yahoo.com/group/dxlist/ http://groups.yahoo.com/group/themixwgroup http://groups.yahoo.com/group/contesting http://groups.yahoo.com/group/wnyar http://groups.yahoo.com/group/Omnibus97 Yahoo! Groups Links Title: Modes HF Digital Modes Band Select a Band 160 Meters 80 Meters 40 Meters 30 Meters 20 Meters 17 Meters 15 Meters 12 Meters 10 Meters Mode Options Select a Chat Mode PSK31-Chat PSK63-Chat PSK125-Chat DomainoEX11-Chat DomainoEX22-Chat MFSK16-Chat Select a Send File Mode PSK63- end File PSK125-Send File MFSK16-Send File Select E-Mail PSKMail-EMail
Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110
I was able to find some interesting data on poor channel performance of the 110A modem from one company: http://www.etools.de/software/telekommunikation/komponenten/milstd188110a.htm Depending upon the BER you can tolerate, it appears that the 2400 bps speed can only handle around +10 to +14 S/N dB. The slower bps rates can work to around zero S/N. Te 150 bps shows something around -1 to -4. Another interesting specification is the the multipath tolerance. They claim 6 msec at 2400 bps, 8 ms from 150 to 1200 bps, and 12 mec at 75 baud. That seems to have good ability to cope with ISI. Now these are the bps rates. Isn't the baud rate the same 2400 baud, all the time for this modem, contrary to what Bonnie claims? 73, Rick, KV9U expeditionradio wrote: --- In digitalradio@yahoogroups.com, kv9u [EMAIL PROTECTED] wrote: If the 110A works this well at 2400 baud, what would happen with slower speeds? From what I understand, it does require a good signal to get through, perhaps comparable to the WinDRM software at maybe +10 S/N dB or maybe a bit below that? 73, Rick, KV9U Hi Rick, Your understanding is not correct. The lower baud rates of the 188-110 PSK system work in *negative SNR*. That is much farther down into the noise than DRM. May I suggest you download RFSM2400 and receive some of the signals on the air. This might give you a better feel for it. Bonnie KQ6XA .
Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110
Bonnie, Your definition below is not at all my understanding, nor does it square with anything that I have read on baud rate. My understanding for many years has been that baud refers to the symbol rate per second. In other words, the actual changes or transitions taking place per second. The rate of data throughput (the signaling rate) is often expressed as bits per second (bps). Some baud rates may allow for more data throughput in bps than the baud rate because one symbol can carry more than one bit depending upon the modulation scheme. What do you consider the baud rate to be, if not the symbols per second? KV9U expeditionradio wrote: Rick, KV9U wrote: Isn't the baud rate the same 2400 baud, all the time for this modem, Hi Rick, Perhaps you have been confusing baud and symbols per second. This is a common mistake many hams have with complex digital formats. To answer your question... The MIL STD 188-110 serial PSK modem signal on the air is 2400 symbols per second. The non-standard RFSM2400 is 2000 symbols per second. The baud rate, determined by coding, may change. The symbol rate stays constant. The baud rate may be as low as 75 baud or as high as 4800 baud. If your issue is about how this affects your FCC compliance, the answer to that is: 1. These modems do not exceed FCC's limit for sending image or voice content in the image/voice subbands... because there is no FCC symbol rate limit in the image/voice subbands. 2. These modems do not conform to FCC's arbitrary 300 symbol per second limit for the USA ham radio HF RTTY/data subbands. Do not pass Go. Do not collect $200. Stay in Technology Jail. :) Bonnie KQ6XA
RE: [digitalradio] Re: RSM2400 / MIL-STD-188-110
Walt, I would rather have ONE mode that is scalable so that you could merely adjust it according to the demand, speed vs SNR, etc. Please write to me off-line if you plan to attend HAMCOM in Dallas. I think I owe you a case of wine or something. 73, John K8OCL Original Message Follows From: DuBose Walt Civ AETC CONS/LGCA [EMAIL PROTECTED] Reply-To: digitalradio@yahoogroups.com To: digitalradio@yahoogroups.com Subject: RE: [digitalradio] Re: RSM2400 / MIL-STD-188-110 Date: Fri, 16 Mar 2007 15:27:23 -0500 What if an individual wants high speed AND good low signal leveel throughput? I think the first thing is that individuals need to decide what USER throughput they want in CPS or WPM or PPM and then at what the lowerest SNR they expect the mode to provide 95% copy (or some percent of perfect). As Dave AA^YQ has said, there may not be one mode that works for all bands and under all scenerios...so more than one mode may be called for. IMHO a chat mode need not provide for more then 60 or so WPM but you might want it to provide 95% copy at a -15 dB SNR and you don't care what the bandwidth is as long as its small. On the other hand you may to esnt ASCII and binary files from point to point with a throughput so that a 40 Kbps file can be sent in 5 milutes or less and the mode must give 98% copy at a -10 dB SNR and if it shold have an ARQ feature that can be turned on to give you 100% copy for binary. You might wind up with a suite of modes call from a menu such as attached. Walt/K5YFW -Original Message- From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of John Champa Sent: Friday, March 16, 2007 2:57 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110 Poor Bonnie! We are hitting you from both directions: --some want better weak signal performance at the cost of speed (~HF) --some want more speed at the cost of signal performance (~10M VHF) Original Message Follows From: kv9u [EMAIL PROTECTED] Reply-To: digitalradio@yahoogroups.com To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110 Date: Fri, 16 Mar 2007 09:32:30 -0500 If the 110A works this well at 2400 baud, what would happen with slower speeds? From what I understand, it does require a good signal to get through, perhaps comparable to the WinDRM software at maybe +10 S/N dB or maybe a bit below that? 73, Rick, KV9U Per wrote: Well, MIL-STD-188-110A uses a single phase shifted tone , I guess that made it even more non-intuitive ? The difference between packet and this MIL-STD is just huge. Interleaver to fight fade and QRM, equalization to benefit from multipath and the list could just go on and on. 300 baud packet is a joke. 73 de Per, sm0rwo Announce your digital presence via our DX Cluster telnet://cluster.dynalias.org Our other groups: http://groups.yahoo.com/group/dxlist/ http://groups.yahoo.com/group/themixwgroup http://groups.yahoo.com/group/contesting http://groups.yahoo.com/group/wnyar http://groups.yahoo.com/group/Omnibus97 Yahoo! Groups Links test.html
Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110
Rick, Now that is some interesting research! More please. Thanks, John K8OCL Original Message Follows From: kv9u [EMAIL PROTECTED] Reply-To: digitalradio@yahoogroups.com To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110 Date: Fri, 16 Mar 2007 17:00:21 -0500 I was able to find some interesting data on poor channel performance of the 110A modem from one company: http://www.etools.de/software/telekommunikation/komponenten/milstd188110a.htm Depending upon the BER you can tolerate, it appears that the 2400 bps speed can only handle around +10 to +14 S/N dB. The slower bps rates can work to around zero S/N. Te 150 bps shows something around -1 to -4. Another interesting specification is the the multipath tolerance. They claim 6 msec at 2400 bps, 8 ms from 150 to 1200 bps, and 12 mec at 75 baud. That seems to have good ability to cope with ISI. Now these are the bps rates. Isn't the baud rate the same 2400 baud, all the time for this modem, contrary to what Bonnie claims? 73, Rick, KV9U expeditionradio wrote: --- In digitalradio@yahoogroups.com, kv9u [EMAIL PROTECTED] wrote: If the 110A works this well at 2400 baud, what would happen with slower speeds? From what I understand, it does require a good signal to get through, perhaps comparable to the WinDRM software at maybe +10 S/N dB or maybe a bit below that? 73, Rick, KV9U Hi Rick, Your understanding is not correct. The lower baud rates of the 188-110 PSK system work in *negative SNR*. That is much farther down into the noise than DRM. May I suggest you download RFSM2400 and receive some of the signals on the air. This might give you a better feel for it. Bonnie KQ6XA .
RE: [digitalradio] Re: RSM2400 / MIL-STD-188-110
Bonnie, Have you ever used HF-CPSHF? John Original Message Follows From: expeditionradio [EMAIL PROTECTED] Reply-To: digitalradio@yahoogroups.com To: digitalradio@yahoogroups.com Subject: [digitalradio] Re: RSM2400 / MIL-STD-188-110 Date: Fri, 16 Mar 2007 01:27:04 - John K8OCL wrote: Haven't the HF-LINK folks been using this mode for over 5 years? Hi John, Yes. MIL STD 188-110 is in PCALE software (along with standard ALE). Operators have been using -110 (outside USA) for data files. I was using the RFSM2400 while I was in Hong Kong, China. It is a good system, and the modified narrow version takes no more bandwidth than some other digital modes or SSB voice. As you know, USA has an arbitrary 300 symbol/second limit in the USA Data Subbands. But there is no such 300 baud limit in the phone and image subbands, so some of us in USA have used -110 to send image files. It does that quite well, but the real forte of -110 is data FTP and email. Wow... 2007... a shame that USA hams are living under those antiquated FCC rules made for the previous century's technology. USA hams still sit rotting in the FCC's technology jail. The rest of the world's hams can use RFSM2400 freely for data or mail. Bonnie KQ6XA
[digitalradio] Re: RSM2400 / MIL-STD-188-110
Hi Bonnie, Excuse me for being dense (is what I do best)...is the difference in this discussion MIL-STD-188/110 versus MIL-STD-188/141A ? I know the /xxx takes precidence; as do all slash sheets. But am missing the point (I should read the MIL specs, but have to do that everyday at work so wince at doing so at home); is the bottom line that -141A is legal in the US but -110 is not? Thanks in advance, Bill N9DSJ --- In digitalradio@yahoogroups.com, expeditionradio [EMAIL PROTECTED] wrote: John K8OCL wrote: Haven't the HF-LINK folks been using this mode for over 5 years? Hi John, Yes. MIL STD 188-110 is in PCALE software (along with standard ALE). Operators have been using -110 (outside USA) for data files. I was using the RFSM2400 while I was in Hong Kong, China. It is a good system, and the modified narrow version takes no more bandwidth than some other digital modes or SSB voice. As you know, USA has an arbitrary 300 symbol/second limit in the USA Data Subbands. But there is no such 300 baud limit in the phone and image subbands, so some of us in USA have used -110 to send image files. It does that quite well, but the real forte of -110 is data FTP and email. Wow... 2007... a shame that USA hams are living under those antiquated FCC rules made for the previous century's technology. USA hams still sit rotting in the FCC's technology jail. The rest of the world's hams can use RFSM2400 freely for data or mail. Bonnie KQ6XA
Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110
It still seems a bit non-intuitive that using a 2400 baud rate with two tones can work well and yet 300 baud packet hardly works well at all. There is something that I am missing here. 73, Rick, KV9U expeditionradio wrote: Yes. MIL STD 188-110 is in PCALE software (along with standard ALE). Operators have been using -110 (outside USA) for data files. I was using the RFSM2400 while I was in Hong Kong, China. It is a good system, and the modified narrow version takes no more bandwidth than some other digital modes or SSB voice. As you know, USA has an arbitrary 300 symbol/second limit in the USA Data Subbands. But there is no such 300 baud limit in the phone and image subbands, so some of us in USA have used -110 to send image files. It does that quite well, but the real forte of -110 is data FTP and email. Wow... 2007... a shame that USA hams are living under those antiquated FCC rules made for the previous century's technology. USA hams still sit rotting in the FCC's technology jail. The rest of the world's hams can use RFSM2400 freely for data or mail. Bonnie KQ6XA
[digitalradio] Re: RSM2400 / MIL-STD-188-110
John K8OCL wrote: Haven't the HF-LINK folks been using this mode for over 5 years? Hi John, Yes. MIL STD 188-110 is in PCALE software (along with standard ALE). Operators have been using -110 (outside USA) for data files. I was using the RFSM2400 while I was in Hong Kong, China. It is a good system, and the modified narrow version takes no more bandwidth than some other digital modes or SSB voice. As you know, USA has an arbitrary 300 symbol/second limit in the USA Data Subbands. But there is no such 300 baud limit in the phone and image subbands, so some of us in USA have used -110 to send image files. It does that quite well, but the real forte of -110 is data FTP and email. Wow... 2007... a shame that USA hams are living under those antiquated FCC rules made for the previous century's technology. USA hams still sit rotting in the FCC's technology jail. The rest of the world's hams can use RFSM2400 freely for data or mail. Bonnie KQ6XA
Re: [digitalradio] Re: RSM2400 / MIL-STD-188-110
Now I'm I missing something - I don't seen to have a problem with HF packet. But then again I don't use a sound card for it either. At 09:29 PM 3/15/2007, you wrote: It still seems a bit non-intuitive that using a 2400 baud rate with two tones can work well and yet 300 baud packet hardly works well at all. There is something that I am missing here. 73, Rick, KV9U
[digitalradio] Re: RSM2400 / MIL-STD-188-110
Doubt you or Rick are missing anything. 300 baud ax.25 packet works poorly on HF unless near the MUF. I still like the mode but after 20+ years I agree to its shortcomings... PAX/PAX2/ARQ FAE all work better at the expensive of bandwidthax.25 packet at 110 baud works better too when down from MUF (although slow). All seem a compromise, but they all provide ARQ... a trade-off in speed versus bandwidth.. Bill N9DSJ --- In digitalradio@yahoogroups.com, John Becker [EMAIL PROTECTED] wrote: Now I'm I missing something - I don't seen to have a problem with HF packet. But then again I don't use a sound card for it either. At 09:29 PM 3/15/2007, you wrote: It still seems a bit non-intuitive that using a 2400 baud rate with two tones can work well and yet 300 baud packet hardly works well at all. There is something that I am missing here. 73, Rick, KV9U
