[HamWAN PSDR] 1.2GHz to Paine [was: 44.x.x.x HamWAN network at Paine]

Wed May 28 17:12:48 PDT 2014

This is some really broad strokes.  Are there specifics on ID-1 protocol 
/ framing somewhere?

--Bart

On 5/27/2014 4:59 PM, John D. Hays wrote:
> ID-1 simply encapsulates an Ethernet frame behind a D-STAR header. 
>  The header has some correction, but the Ethernet frame is not 
> corrected by D-STAR.
>
>
> ------------------------------------------------------------------------
> John D. Hays
> K7VE
> PO Box 1223, Edmonds, WA 98020-1223
> <http://k7ve.org/blog> <http://twitter.com/#%21/john_hays> 
> <http://www.facebook.com/john.d.hays>
>
>
> On Tue, May 27, 2014 at 4:28 PM, Bart Kus <me at bartk.us 
> <mailto:me at bartk.us>> wrote:
>
>     There's no protocol I'm aware of that implements these features on
>     top of ID-1.  You'd need the ability to receive corrupt frames
>     from the ID1 to allow the use of FEC.  How does the ID1 handle
>     corrupt frames?  Is there a CRC or something in the framing?  For
>     ARQ, you could keep the TX retrying until it hears an ACK or times
>     out.  Custom software would be needed, or perhaps pppd can do such
>     tricks, I dunno.
>
>     Did you hear any signal when you listened with an FM receiver? 
>     Can you use an RTL-SDR or equivalent to see if there's any signal
>     present?
>
>     --Bart
>
>
>     On 5/24/2014 8:36 PM, Dean Gibson AE7Q wrote:
>>     That's what I figured ("features [that] are common to all WiFi
>>     systems"); it just made sense (although that is not always
>>     determinative!).
>>
>>     So, my next question:  Is there an available tunneling protocol
>>     that employs those features?
>>
>>     Note that with the ID-1 in the *one watt* setting (same omni
>>     antenna), I can use the 1.2GHz KB7CNN repeater 35 miles away on
>>     East Tiger mountain, with no noise in the FM signal. The link to
>>     Paine (5 miles away) was tried at max power (ten watts) on both
>>     radios.  I tried two different frequencies (that's the beauty of
>>     being able to control both radios from one location!): 1.250GHz
>>     and 1.249GHz (I listened on both in FM mode), with no significant
>>     difference.  So, in my opinion, it's a path problem.
>>
>>     On 2014-05-24 13:13, Bart Kus wrote:
>>>     Wow that sucks.  :(  Is the signal level just too low?  Is it a
>>>     matter of interference?
>>>
>>>     And yeah, I can confirm that the microwave stuff we use includes
>>>     both FEC (at up to 1/2 rate) and an ARQ system (look at
>>>     "hw-retries" setting).  These features are common to all WiFi
>>>     systems too, and they're just carried over into our NV2 TDMA system.
>>>
>>>     --Bart
>>>
>>>     On 5/24/2014 10:19 AM, Dean Gibson AE7Q wrote:
>>>>     Scott Honaker and I have moved forward on this project:
>>>>
>>>>      1. We have installed a gateway (Linksys BEFSR41) between the
>>>>         ID-1 and the internal ARES/RACES subnet (not 44.x.x.x) of
>>>>         the DEM.
>>>>      2. We have installed a Digi "AnywhereUSB" box to give us
>>>>         remote access to the ID-1's USB port, and thus remote
>>>>         control of the ID-1 radio.  This not only allows multiple
>>>>         use of the ID-1 (which has useful 1.2GHz FM and digital
>>>>         voice modes as well as Ethernet data), but provides for
>>>>         remote frequency agility and a diagnostic capability. This
>>>>         works beautifully (eg, to search for and use a low-noise
>>>>         frequency)!
>>>>
>>>>     Unfortunately, what does not work very well, is the RF portion
>>>>     of the connection.  PINGs failed at a rate of over 99% when
>>>>     using the 1.2GHz antenna at the 70 ft level on the tower, so we
>>>>     swapped the antenna with the one used for the Icom 1.2GHz
>>>>     repeater (which wasn't seeing any action anyway) at 100 ft. 
>>>>     That made a "dramatic" improvement, as PINGs now only fail at a
>>>>     98% rate (depends upon the time of day, etc)!
>>>>
>>>>     Antenna comparison between 1.2GHz and 5.9 GHz for the two sites:
>>>>
>>>>      1. On 1.2GHz, both antennas are omni-directional.
>>>>      2. At the DEM, the 1.2GHz antenna is now at the 100' level,
>>>>         whereas the 5.9GHz antenna is at 150'.
>>>>      3. At my home, the 1.2GHz antenna is about 10' above the
>>>>         5.9GHz antenna, and it's on the same line-of-sight path.
>>>>
>>>>     Note that voice communication between the two sites using the
>>>>     two ID-1 radios, is fine (there is a slight bit of noise on FM).
>>>>
>>>>     The big difference, in my opinion?  I'll bet that the wireless
>>>>     protocol used by the MikroTik radios includes an aggressive
>>>>     error correction and retry protocol, whereas the ID-1 is like a
>>>>     piece of Ethernet cable, and thus relies on the standard TCP/IP
>>>>     retry mechanism.  The TCP/IP protocols, while "unreliable" in
>>>>     the technical sense of the term, require a higher overall
>>>>     reliability than a typical raw wireless connection.
>>>>
>>>>     What this says (and I'm a bit surprised to note this), is that
>>>>     sites considering using ID-1 radios for data communications,
>>>>     may find that even with the tighter siting requirements of
>>>>     5.9GHz, that the latter may be more successful (whether or not
>>>>     part of HamWAN).  In addition to being a lower-cost radio with
>>>>     a much higher data rate, the MikroTik radios offer a built-in
>>>>     router, which can obviate the need for a separate router.
>>>>
>>>>     -- Dean
>>>>
>>>>     ps: The callsign and digital code filtering features of D-Star
>>>>     that we previously discussed, are not available (greyed out in
>>>>     the software) for digital *data* mode.  Huh?  Another fine
>>>>     example of software of the "seven last words" of poor program
>>>>     design: *"Why would you want to do that?"*
>>>>
>>
>>
>>
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