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I'm looking around for a decent GPS module for a project of mine. The Sparkfun GPS Buying Guide is nice, but focuses mostly on modules with patch antennae.

My project is a wrist- or upper-arm-mounted GPS logger. It will be displayless and log continually, and thus there can be no assumptions about the orientation of the device (as there probably could be if the user were to read a display). As far as I've understood, this means I should go for a helical antenna instead of a patch one for better omnidirectionality. Is this correct?

If so, does anyone have any recommendations for a decent (and decently priced) GPS module with a helical antenna? An antenna-less module with a third-party antenna is also possible, but I'd prefer a complete module. The last time I looked into this a few months ago, the most interesting device I found was the Falcom FSA03 based on the u-blox UBX-G5010. I also see there's a UBX-G6010 based FSA03-LP out now. Does anybody have any experience with these?

Edit: I've also been hearing about PCB loop antennae. Any experiences with those? From what I've understood, these are often used in cellphones...

I don't have very specific requirements, but the size should be small. I'm not looking for the tiniest of the tiny, but it shouldn't be bulky either - this is vague, I know, but I'm looking for something suited to a small wrist-mounted device. Low power consumption is important. And of course, the more reasonably priced, the better.

Thanks in advance for any recommendations!

Conclusion (in case anybody comes across this at a later point): I went for a u-blox LEA-6H module ($50 on eBay) and a Sarantel SL1300 antenna (€10 at Mirifica). I haven't had the time to try things out yet, but it seems to be exactly what I need.

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closed as off-topic by Nick Alexeev Jul 2 '15 at 3:47

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    \$\begingroup\$ Helical does decrease the polarization issue by sacrificing a little bit of gain all the way around to avoid massive loss of gain in certain polarization scenarios. However, you do still have right hand vs. left hand to deal with if the GPS satellites use circular polarization. Not sure about that at the moment... \$\endgroup\$ – Brian Knoblauch Jan 17 '11 at 14:41
  • \$\begingroup\$ Try a PCB spiral antenna. Its smaller and is circularly polarized too. \$\endgroup\$ – Jorge Aldo Feb 16 '15 at 15:58
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As far as commercial-off-the-shelf, SparkFun sells a helical antenna based receiver, also using the u-Blox chipset, the GS407 Helical GPS Receiver. It's using a Sarantel SL1206 Antenna. You may be able to find more antennas to your liking directly available from Sarantel. Also, if you are eventually looking to embed this into a product, purchasing from SparkFun may prove to be more costly, so going directly from the manufacturer may save money. One drawback to the SparkFun product is that it's limited to 4Hz update, according to the datasheet, and 2Hz according some of the comments on the product page.

If you are feeling more DIY, then you can check out this page of DIY GPS antennas.

If you are looking for more ideas, it might be worthwhile to purchase a few of the "runners watches" that are currently available on the market and see what they do. I know that Garmin and the like manufacture these in pretty tightly-integrated packages, so they have approached the problem before.

Also, as an additional data point, I believe that the iPhone uses a patch antenna (I wouldn't imagine that there is much room for much else in there), and it seems to successfully track me when mounted on my arm during runs, so patch may be a viable option with some clever design.

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  • \$\begingroup\$ Thanks a lot for the feedback. I'm aware of the GS407 from Sparkfun, but it seems a bit pricey. The update rates are no problem, even 1 Hz would be no problem for my applications. Thanks for the tip on runners' watches, although my project is a single-build hobby project (for fun) not meant for production so my budget won't allow such things. I'll probably end up with a Sarantel SL1300 attached to some reasonably priced module. \$\endgroup\$ – gspr Jan 17 '11 at 22:58

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