AIShub, how you too can put AIS targets online

... written for Panbo by Ben Ellison and posted on May 11, 2012

At the end of Wednesday's discussion about cell-based mAIS -- which only works via the Internet instead of direct VHF radio transmissions -- I mentioned how I'd set up a real AIS receiver in my lab to forward real AIS target info to those same Internet services. In fact most all the actual AIS targets shown in those screen shots came through my basement. The set up turned out to be very easy and cost nothing as I already had an AIS receiver, a computer, and an Internet connection. The key is the free program AISdispatcher seen in the foreground above, which is offered by AIS Hub data sharing center. That's their Web site in the background, showing the data I'm contributing along with that of other volunteer stations. But there are lots of holes in the coverage and I'm hoping that more coastal residents and particularly marine businesses will volunteer, and I think that the new mAIS concept could make the effort especially worthwhile... 

But before theorize about the brave new world of mAIS and AIS on the Internet, I'll explain more about AIS Dispatcher and my lab setup. The status screen below left shows approximately a full day's output, which goes to AIS Hub, MarineTraffic, and ShipFinder without any more setup than registering with AIS Hub. Note the Output Bandwidth use of 0.004 KB/s; my location and antenna situation, and the season, results in a paltry average target count of about 3, but you could "dispatch" hundreds of targets without denting your Internet connection.
   I also like how AIS Dispatcher parses the NMEA 0183 VDM strings and counts the individual AIS messages they contain. For instance, the ratio of Class B dynamic and static data messages -- #18 and #24 -- jibes with the reality that the one Class B I've been seeing is mostly tied up at Wayfarer Marine; since message 24 is fixed at six minute intervals, most of the time the boat was sending #18 messages at the under 3 knot rate of every three minutes. To better understand what those message counts mean see the USCG NavCen's message detail and this Panbo about Class A & B dynamic data rates.
  But I digress. While I think it's good for boaters to understand how the AIS works, it's not necessary for setting up an AIS listening station. Aside from registering with AIS Hub I only had to tell AISdispatcher which com port the receiver was on (as seen below right), type in the output address they emailed me, and that was it. Well, I also set up GpsGate Express -- the green icon lower right and another freebie -- so that I can still access the AIS receiver with other software, but that too just took minutes, not hours...


It also happens that my AIS receiver doesn't have USB output and the computer doesn't have an old style serial input but a Keyspan 19HS adapter takes care of that issue. And today there are AIS receivers with USB output, like the Comar AIS-2-USB, and even receivers designed for dispatching without having to leave a computer running, like the Digital Yacht AISNet Base Station, which I wrote about in 2010. There's a good run down on all this at Marine Traffic, which also has its own free dispatcher software. 
   These online AIS services also have sophisticated monitoring of their volunteer stations, as you can see by turning on More/Stations on MarineTraffic's Live Map or going to this AIS Hub page. In either case you can get a graph of a station's performance and much more. Thus you can see how paltry my feed is, which is due to the season -- no visiting yachts yet -- and especially to my poor antenna and antenna location. But all this is really just an experiment with one goal being to persuade some locals with better locations and even more motivation to become volunteer AIS stations...  


Like how about Wayfarer Marine? Note how their site already offers an online weather station, which appears in more detail as a Weather Underground Station (and was set up largely by Panbot Allan Seymour of the good tug Sally W). That station is great for locals and  Wayfarer customers and probably especially staff who are home but worried about what's happening at the yard during storms. An AIS receiver would co-habitat nicely and easily with the dock house PC that's hosting the weather station and I think that many customers, not to mention me, would like to see their AIS-equipped vessel online when it's in the area. Wayfarer could even put up a ShipFinder or MarineTraffic widget like I'm testing at the bottom of the Panbo About page.
   Now think about how mAIS might fit in. Customers, visitors, and locals without regular AIS could also show up on the Web widget, iPad apps, etc. Wayfarer staff delivering boats down the coast could be monitored on the same office screen as real AIS targets. Remember that mAIS doesn't need a shore receiver to be seen online, just a cell connection. And when the Penobscot Bay Regatta fires up in August, all the sail races and powerboat cruises off Camden could be tracked as long as the vessel has a real AIS or a smartphone running mAIS. Ships and ferries too, though they will not be bothered by the mAIS unless they choose to look. (By the way, I'm going to be the "powerboat guide" for this year's PBR; more on that soon, but do consider signing up.)
   Yesterday I got an email asking about setting up an AIS shore station from Captain Ethan Maass of Sea Tow South Shore and it seems to me that there's tons of useful and just plain interesting information the combination of mAIS and an AIS shore station can provide his customers and community, and his business. Heck, I wonder if SeaTow won't eventually add mAIS tracking and online AIS viewing to its already useful app. I know it's confusing, but obviously I'm enthused about the possibilities here.
   And, by the way, there can't be too many shore stations. As this map showing the output of one AIS Hub station in Seattle shows, the servers can see and handle duplicate target reports. If you have a good antenna view toward navigable water, and especially if you're a marine business, please consider joining the global and publicly available AIS listening network.



As poor as my antenna and location are, I am seeing Acadian 20 miles down the Bay:

Posted by: Ben at May 11, 2012 2:01 PM | Reply

Yes, AIS Hub is a good outfit. If you contribute your AIS feed, you can get the NMEA feed from their global network via a TCP/IP port. This comes in handy if you are developing AIS tools. For example, while I was waiting for the U.S. approval of Class-B transponders, I had access to data from Europe, allowing me to test NavMonPc with live Class-B messages.

I've been an AIS Hub station for several years now (I'm "San Francisco"). My best range is a bit over 2000 nautical miles, but generally I only receive out to 100 miles or so. The antenna is at 1000 ft overlooking the ocean, with some hills blocking the signals from the north.

Posted by: Paul at May 11, 2012 9:53 PM | Reply

Thanks, Paul. I can see from the AIS Hub stats that you've been a pretty faithful contributor. I also see that both your station and Monterey are now tracking a ship called TAIO DREAM that's nearly at the latitude of Cabo San Lucas and maybe a fifth of the way to Hawaii.

Wow. What sort of antenna and receiver are you using? Or is that some sort of ducting phenomenon?

Posted by: Ben in reply to Paul at May 12, 2012 9:28 AM | Reply

Ben, interesting stuff. Wouldn't it be possible for any vessel with an installed AIS and onboard computer, with the ability to connect to shore-based Wifi networks, to act as a "Hub Station"? I can see great possibilities for extending the AIS coverage to remote areas without land-based AIS stations, but WITH wifi capability and plenty of visiting vessels. Of course, the AIS output on the boat would have to be "split" to a port on the PC, if it is currently connected to another display or device...

Posted by: Grant at May 12, 2012 11:12 AM | Reply


I'm one of the other Seattle guys and have been sharing for just about a year now. My set up early on was similar to what you are running currently in your lab. After a while though, I got tired of needing to maintain the service on my constantly changing pc. I had a few wired network serial device servers I'd picked up on ebay to do some 0183 work on my boat, and thought I'd try UDP-ing the sentences in to AIShub directly with one. Bingo, it worked perfectly! now I have a robust connection that recovers quickly following power or network outages.

Receiver: Icom MXA 5000
Serial server: Quatech qse-100

Posted by: Evan at May 12, 2012 12:05 PM | Reply

Thanks for the mention and thanks for the coverage of Penobscot Bay.
Everybody around should thank you as well. Now we can see more of what is happening our little busy body of water. Even the Maine ferries have gotten into the act!

Posted by: Allan Seymour at May 12, 2012 7:07 PM | Reply

Ben, I've got a plain-vanilla AIS setup: A marine VHF tall whip on top of the barn feeding a SR-161 (single-channel) AIS receiver. The receiver serial port is connected to a RS-232 / Ethernet adaptor, then to an old netbook that connects to the AIS Hub server. I actually feed several servers, not just AIS Hub, and get their feeds for my own use in return.

The DX reception is due to tropospheric ducting, and at 1000 ft elevation we are well-situated at the marine-layer (fog) boundary. The range all depends on the weather. On clear days we see out just past the horizon, but when the conditions favor ducting we often have coverage to the tip of Baja California (and occasionally halfway to Hawaii).

On my boat I have a Class-B transponder, with the antenna on the upper spreader. We usually receive out to the horizon, or a little bit farther, but on some days we receive 200+ miles. I assume our transmit range is somewhat less, due to our low-power Class-B signal. As far as I'm concerned, anything beyond six miles is just gravy.

Posted by: Paul at May 13, 2012 1:36 AM | Reply

Thanks Ben for promoting AISHub :)

Posted by: Peter at May 24, 2012 5:38 PM | Reply

Happy to report that AIShub ran for about two weeks straight without a problem. I stopped it briefly this weekend to try out an Em-Trak R100 AIS receiver, which worked very nicely and was super easy to set up because it can both get power and deliver data via USB. Windows 7 found its drivers too (and it comes with CD of drivers for other operating systems). And it's only $220 at West Marine:

Unfortunately my antenna location has gotten worse as the tall trees around my house have fully leaved out, especially when it's raining hard like it is now. Hopefully the R100 will soon be operating from a better site overlooking Penobscot Bay.

Posted by: Ben at May 29, 2012 9:43 AM | Reply

I have my AISNet Base Station up and running now and have filled a gap in coverage for here in Cape Cod Bay. Very happy with the AISNet and it was extremely easy to setup.

Thanks for the guidance Ben!

Posted by: Ethan Maass - Sea Tow at June 7, 2012 10:26 AM | Reply

That's great, Ethan. Did you know that if you enable More/Stations on the top left of Marine Traffic you can see all sorts of stats for "Sea Tow South Shore" like the fact you're covering some 1,700 square kilometers?

I ran into Wayfarer's dockmaster this morning and he whipped out his iPhone to show me how he was tracking Belle Adventure up the Bay via my little receiving station (stats at AISHub but showing on Marine Traffic too). Thus he knew just when he needed to clear some dock space, and when he'd see his girlfriend ;-)

I really don't know why I didn't try this sooner or why more businesses like yours don't set up a station.

Posted by: Ben in reply to Ethan Maass - Sea Tow at June 7, 2012 10:54 AM | Reply

Oops, a Google "expert" is wrong when he claims that public AIS tracking is better than what the Navy, Coast Guard, etc. are doing. Anyone surprised?

Posted by: Ben at June 9, 2012 8:42 AM | Reply

Cool. If you go to MarineTraffic, enable "More/Stations", and click on the Camden one, you'll see that it's with receive statistics, etc. It turned out to be easy to register at Marine Traffic and get a unique port address that I could add to AISdispatcher.

You may also see a station in Rockland that's actually onboard the yacht Knickerbocker. I haven't seen this before but if you have AIS going to an onboard computer that's also online, it's quite easy to be a moving AIS-to-Web receiving station. Very cool, I think.

Posted by: Ben at July 17, 2012 2:48 PM | Reply

My brother-in-law reports seeing over 100 AIS targets in the Newport, RI, area yesterday via his Class B responder. But only a small fraction of those show up on Marine Traffic and other public online AIS sites.

Why? Because so few marine businesses and boaters who live near the coasts have set up volunteer receivers, even though it's pretty easy and inexpensive. Please do it!

Posted by: Ben at July 11, 2013 8:21 AM | Reply

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