SparkFun Forums

[baluba]

Evolution in GPS world is progressing blazingly fast, with dropping sizes and, hopefully, prices.

Don't know price of these but some of these new ANTARIS4 GPS modules are only 17 x 22.4 x 3, uses half the power of the ET-301 module, has faster startup times, and has -150dBm sensitivity ...

erik

[sparky]

How cool is that! Looks like it could be two ICs + a filter to get to hobby GPS boards. That would be fun! Unfortunately the ICs are non-existant for the moment and the dev kit from Digikey is $600.

Thanks for the heads up though!

-Nathan

[coyotebush]

The nice thing is, the Antaris chipset provides high quality phase information. It can be used for precise positioning - submeter GIS and possibly cm survey measurements. The "indoor" S version is particularly attractive; it should work under the trees.

The Sirf III is also sensitive, but it doesn't provide the phase information needed for precise work. It was very disappointing to interface to the Sirf III, and then discover the phase measurements were all set to zero.

Caveat: I haven't actually seen an Antaris 4 yet. I'm assuming they haven't crippled the phase measurements like Sirf did with the Sirf III.

[coyotebush]

Another thought: If you were to do an Antaris4 board, allow the antenna voltage to be jumpered at either 3.3V or 5V. Most survey antennas are 5V.

FYI. U-blox is offering a development kit for $199.

[coyotebush]

Another update. Of the Antaris4 modules, only the LEA-4T provides carrier phase. The corresponding AEK-4T evaluation kit is $350 from u-blox.

[jbeale]

The AEK-4T receiver is impressive. I put it on top of a hill with a clear sky view and watched the NMEA output in real time for 20 minutes. Location was N37.427092 W122.073517. In those 1200 position fixes, ALL (100%) of them were within an oval shape with diameter 100 cm N/S and 50 cm E/W. There was continual wander within that, it did not lock to one output. When I tried it on a car driving around, it appeared to match up quite precisely to the map, with no averaging etc.

[leon_heller]

Evolution in GPS world is progressing blazingly fast, with dropping sizes and, hopefully, prices.

Don't know price of these but some of these new ANTARIS4 GPS modules are only 17 x 22.4 x 3, uses half the power of the ET-301 module, has faster startup times, and has -150dBm sensitivity ...

erik

I haven't had any problems getting an LEA-4A from u-blox, and my client supplied me with the dev kit.

With the active antenna it's very sensitive and acquires the data very fast.

I'm using one with the Siemens MC55 GSM modem module, they are both about the same size. I think I could get a complete tracker in about 3 cm x 3 cm by putting the MCU and SIM under the MC55, with the LEA-4P on the other side. The battery is really the limiting factor.

Leon