Garmin 2.6 Nuvi Update SiRF InstantFixII

Over the past couple of months we have had numerous people writing to us to say that they have been having trouble getting satellite reception in their Nuvi 700 series devices, and a few people reporting similar problems with Nuvi 200 series devices. These reports prompted our article about tips for GPS satellite reception which helped a few people out. It didn’t completely solve the problem for all users though. But since Garmin’s update version 2.6 and something called SiRF InstantFix (now version II), those troubles have largely gone away.

I had seen some of the troubles myself with a Nuvi 760. After both had been turned off for more than 48 hours I took a Nuvi 200 and the 760 outside with an unobstructed sky view and turned them on. The 200 connected in less than two minutes while the 760 was seemed confused and didn’t lock on for about 40 minutes. When I performed the same test after the update, the 760 and 200 both acquired a fix within seconds.

After the Garmin Firmware version 2.6 was recently released for Nuvi 700 series models (and 3.6 for some of the 200 series), the acquisition problems have largely gone away according to most user reports. That was from 700 series owners but owners of the Nuvi 260 have also reported similar success.

So how did it suddenly get better? The answer seems to rely with the recently announced SiRFInstantFixII system as users have seen a reference to that phrase on their devices since the update. (Indeed we have now seen it too, click on the image at the right.) How does it work? While most people will just be glad “it works”, here is a more technical description from SiRF.

While in theory determining location using GPS satellites is a simple process of triangulation, the reality is much more complex. First, the GPS receiver needs to find and “lock” onto enough satellites to be able to calculate its location, a process called acquisition. With its 200,000 correlators, SiRF’s innovative SiRFstarIII architecture made the acquisition of satellites very fast. To calculate accurate position, however, the GPS receiver needs to know where each of these GPS satellites is in the sky with a very high degree of accuracy.

Every satellite requires 30 seconds to broadcast its precise location, and the GPS receiver must be able to download this data from each satellite it needs for a fix. This data is typically valid only for two to three hours. If anything interrupts the signal while receiving this data, such as a building or tree, the receiver has to wait another 30 seconds to completely download the data from the satellite.

In real-world conditions, where the GPS receiver is usually moving, it can take up to several minutes to obtain all the data the receiver needs to perform its calculations and obtain a fix, resulting in a long period with a great deal of location uncertainty before navigation can begin.

So if you have a Nuvi 700 series or 260 and you have been experiencing long acquisition times, be sure to fire up WebUpdater and download the latest firmware update. It could make a world of difference for you.

Located in GPS, Garmin on Feb 1, 2008