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[POTM] dAISy - A Simple AIS Receiver

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I didn't see any information about the underlying chipset. But if it's a Si446x with a STM8 it could be workable, if you manage to reprogram the MCU and at least two GPIO pins are connected to it.

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Well, after having a look in my spare parts section I realized I now have quite a number of FM data receiver modules and then I remember this project I have been wanting to look at. The asking price for this old software seems a bit steep and I was wondering if you might like a look also, i.e do the work.

https://www.coaa.co.uk/epirbplotter.htm

It seem a reasonable match to the AIS ,marine safety etc. And since it is on 406MHz not too many alterations would need to be done to the standard 433MHz board. My concept is to include a GPS module with the receiver to provide some indication of direction and distance to a GPS EPIRB transmission. As the last couple of GPS modules I bought only cost US$15 it doesn't seem like too much extra to make the receiver portable.

1st step try and record an EPIRB signal.

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Good news for everyone having difficulties sourcing the Si4362 radio IC.

 

I verified that the transceiver Si4463 works with dAISy. This probably also applies to Si4460 and Si4461. Besides being more widely available through distributors, more adventurous souls can even find these ICs on Aliexpress.

 

Even better news for those that want to recreate my project with minimal effort: Si446x based radio modules are sold on eBay and elsewhere.

 

I bought the E10-M4463D from eBay for $7.99:

http://www.ebay.com/itm/100mw-433MHz-SI4463-Wireless-Transceiver-Module-With-Antenna-2100m-/151243201316

 

I chose this module over others because all pins of the radio are broken out to headers.

attachicon.gifIMG_0844_before.jpg

 

Unfortunately two pins (GPIO2 and GPIO3) are reserved to control the RF switch that connects the antenna with RX or TX channels. But after a few minor changes to my code I had dAISy working.

Here's the branch on Github: https://github.com/astuder/dAISy/tree/E10-M4463D

 

The wiring changed:

GPIO0 -> P2.0

NIRQ -> P2.5

GPIO2, GPIO3 -> no longer connected to the LaunchPad

 

As the modules are built for 433 MHz and AIS is using 162 MHz, I had to replace antenna and passives on the RX side.

attachicon.gifIMG_0851_after.jpg

The new passives from left to right are (ignoring the obvious 0-ohm resistors) 11pF, 150nH, 13pF. As you can see the 0603 components are a very tight fit. I reflowed them with a hot air station instead of using a soldering iron. The clunky thing on the right is a BNC connector, SMA probably would have been a more elegant fit :rolleyes:

 

Technically, it's still not ideal. The traces might be impedance matched to the original frequency. However a quick real-world test demonstrated similar sensitivity as my original breakout boards.

 

EDIT: added wiring information

EDIT: added link to Github

4622.7.png

you wrote 

GPIO0 -> P2.0 (LaunchPad)

NIRQ -> P2.5 ((LaunchPad )

GPIO2, GPIO3 -> no longer connected to the LaunchPad

I can't find NIRQ on board SI4463 433MHz buy on ebay 

It's mean IRQ ?

 

"The new passives from left to right are (ignoring the obvious 0-ohm resistors) 11pF, 150nH, 13pF. As you can see the 0603 components are a very tight fit. I reflowed them with a hot air station instead of using a soldering iron. The clunky thing on the right is a BNC connector, SMA probably would have been a more elegant fit "

11pF, 150nH, 13pF ,0603 components ?

Can you draw a diagram ? i want buy a SI4463 433MHz and modify it

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@@duonglan NIRQ and IRQ are the same.

 

I assume you're referring to this or a similar listing, which looks identical to the module I bought:

http://www.ebay.com/itm/E10-M4463D-SMA-433MHz-Wireless-Transmission-Module-1900m-10mnW-Serial-Port-/121471383928?pt=LH_DefaultDomain_0&hash=item1c48423978

(except for the SMA connector, which mine didn't have)

 

Here's an annotated image of the patched module.

post-9974-0-55582700-1426178051_thumb.png

 

Let me know if you have any other questions.

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thanks , i bought a http://www.ebay.com/itm/E10-M4463D-SMA-433MHz-Wireless-Transmission-Module-1900m-10mnW-Serial-Port-/121471383928?pt=LH_DefaultDomain_0&hash=item1c48423978, hope i will get it soon and do it for myself like you

But i don't understand , how I can upload 4463 WDS configuration ? 

Connect M4463D-SMA 433MHz Wireless Transmission Module and MSP-EXP430G2 v1.5 LaunchPad. Using MSP-EXP430G2 v1.5 LaunchPad upload 4463 WDS configuration ?

sorry , I never used MSP-EXP430G2 v1.5 LaunchPad before, I usually used Arduino

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The radio on its own does not much. It needs an MCU to control it and talk to the computer, which is the MSP430 Launchpad in this case. See the first post of this thread and just replace the custom breakout board with the Ebay radio (minus the changes in wiring as documented).

 

There are several options to program the LaunchPad. For this project I used TI's full IDE Code Composer Studio (CCS).

http://www.ti.com/ww/en/launchpad/software.html

 

The repository I published on Github includes the CCS project file.

https://github.com/astuder/dAISy

Simply copy the whole tree into your CCS workspace and open it in CCS. From there you can compile the code and program the LaunchPad.

 

The radio configuration data generated by WDS is in the radio_config.h source file.

 

dAISy USB is the standalone version of all this, where I designed and built my own PCB that includes radio and MCU on one board.

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Ain't she pretty?

attachicon.gifIMG_1093.jpg

@chicken: I have struggled with SDR and AIS decoding on a Macintosh with little success for some time. I am just about ready to give it up and use your dedicated module if it is still for sale?

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Hi @@haggen

 

Yes, I still sell them. $55 plus shipping. Currently I'm awaiting PCBs from China, so it will take a few weeks before I have a new badge available.

 

Just send me a private message here on 43oh if you're interested.

 

I don't know how well established AIS is on lakes in Switzerland, MarineTraffic only reports a few ships around the port of Basel. So your attempts via SDR might have failed because there's no signal to receive, a situation where dAISy will fail as well. 

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If you have addressed this previously, I apologize in advance. This thread is getting quite long.

 

The better commercial AIS units have dual receivers so that it can monitor both AIS channels simultaneously. Have you considered implementing this?

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The better commercial AIS units have dual receivers so that it can monitor both AIS channels simultaneously. Have you considered implementing this?

 

Currently dAISy does channel hopping. It listens on one channel for a few milliseconds, and if there's no signal jumps to the other and so forth. It can also be configured to only listen on one channel without hopping. From experimentation with that option, I don't think I miss a lot of messages due to hopping.

 

Implementing two separate receivers on one device is on my list, but I didn't do more than scribbling down a few initial thoughts. I'd basically need to duplicate the radio IC with its impedance matching and decoupling passives and probably also the crystal. And of course a splitter. I should have enough pins left on the MSP430F5508 used on dAISy USB, but definitely would need to increase the PCB size.

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Phew, this is starting to get out of hand :)

post-9974-0-43050800-1429405701_thumb.jpg

 

One of the buyers of an earlier prototype 3D-printed a nice case:

post-9974-0-78053700-1429406193_thumb.jpg

post-9974-0-18066400-1429406222_thumb.jpg

That's the form factor I originally envisioned, but never found a matching off-the-shelf case. The BNC connector is too big for most "USB stick" shaped enclosures.

 

I recently updated the firmware to output a serial stream on the spare pins. Works great with a HC-06 Bluetooth module. Obviously won't work if kept within the "official" metal case.

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