Hello Rick, >How difficult would this be to implement the MIL-STD-188-141-B DLP in >software such as Patrick's Multipsk Program? It depends, in general, on the precision of the specifications. If you must reverse-engineers (is it English?) to extract the necessary information, it's long. If all is clear, it cannot be very long except if there are a lot of possible configurations and/or a protocol to manage. However, for instance, I have a lot of other subjects, but in the future who knows...
73 Patrick ----- Original Message ----- From: KV9U To: digitalradio@yahoogroups.com Sent: Tuesday, August 29, 2006 10:06 PM Subject: Re: [digitalradio] Re: ALE QRM is minimal OK Steve, I got the impression that the various modes mentioned below were a part of STANAG 5066 and did not realize that there is a separate DLP part of STANAG 5066. The jargon gets to be a bit much, but very common for military type descriptors. For some reason, the data transfer part of this has not been really talked about much and the focus has been more on ALE. I find the ARQ mode to be the real value in all of this. Assuming it can perform reasonably well. Tell us more about the waveform type, number of tones, and how this works compared to your experiences with the typical sound card modes that we normally use. Is this going to be available for amateur use eventually? How difficult would this be to implement the MIL-STD-188-141-B DLP in software such as Patrick's Multipsk Program? 73, Rick, KV9U Steve Hajducek wrote: >Hi Rick, > >Just time for a quick comment. > >Don't confuse STANAG 5066 Data Link Protocol (DLP) as covered in >MIL-STD-188-141B which is a Data Link Protocol at the Physical Layer >with STANAG 5066 which is a network protocol at the Link Layer. >Basically and DLP with the need ARQ support and speed can be used at >the Physical Layer. If an MT-63 Adaptive ARQ protocol with a >transport layer and enough speed were to develop it could be used. > >STANAG 5066 DLP (S5066) replaced FED-STD-1052 DLP (FS-1052) going >from MIL-STD-188-141A to MIL-STD-188-141B. Both are DLP's that make >use of the MIL-STD-188-110x modems, both provide and ARQ protocol, >where 5066 DLP is much improved. > >We use FS-1052 daily in MARS, we get full 2400bps throughput on a >good channel with stations that are properly configured. We have not >yet implemented S5066, its on the "To Do" list. > >/s/ Steve, N2CKH/AAR2EY > >At 11:16 AM 8/28/2006, you wrote: > > >>One of the main interests that I have in digital modes is getting a >>message through the most difficult conditions, completely intact as >>sent, and as fast as possible. I was looking at the STANAG 5066 >>specifications and test results, (Steve has some below), and quite >>frankly I am concerned that this standard has what I would normally >>consider to be unacceptable performance (non performance) with weak >>signals. >> >>I am not sure what kind of cps or wpm throughput the bit rates mean but >>it I wonder how it compares to SCAMP running at 10 db S/N? Because >>SCAMP only operated down to about +10 db S/N (maybe slightly better), it >>was rejected as unacceptable for practical messaging. >> >> From the info on Steve's site: >> >>http://www.n2ckh.com/MARS_ALE_FORUM/MIL-STD-188-110B.pdf >> >>Here are some claimed performance levels: >> >>Bit rate Multipath SNR BER >> >>4800 2 ms 27 db 1 x e-3 with .5 Hz >>fading BW >>2400 2 ms 30 db 1 x e-3 with 5 Hz >>fading BW >>1200 2 ms 11 db 1 x e-5 with 1 Hz >>fading BW >>300 5 ms 7 db 1 x e-5 with 5 Hz >>fading BW >>75 5 ms 2 db 1 x e-5 with 5 >>Hz fading BW >> >>Even with the slowest 75 bps, and a multipath of 5 ms, it can only work >>down to 2 db ABOVE the noise! This is not good. From personal >>experience, it is not easy to get even 10 db S/N signals with typical >>amateur signals with modest antennas on the lower bands. >> >>They even show some constellations at 64 QAM. From what the SSTV folks >>have said, 64 QAM is not really a useful mode on HF. Perhaps that is >>because they are not using ARQ? >> >>Note also that the multipaths are moderate to low compared to worst case >>HF propagation. I question whether this stuff can work under many >>conditions we routinely operate with sound card modes (but are not 100% >>copy without ARQ). >> >>The BER that this system can handle seems to indicate that the channel >>has to be rather good. These BER's seem to be more appropriate for what >>we would expect on equipment designed for VHF and up ... aren't they? >> >>For those of you who have used STANAG 5066 waveforms, what kind of >>throughput have you experienced with real world connections? >> >>The deeper I examine this NATO standardized agreeement, the more it is >>beginning to look like another one of those "the emperor has no clothes" >>findings. >> >>Thanks and 73, >> >>Rick, KV9U >> >> >> >> [Non-text portions of this message have been removed] 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/ <*> 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/
