The most common handheld GPS question I get these days is about chipsets. People agonize about buying a unit without the SiRFstar III chip, partly because GPS enthusiasts like me have long sung its praises. So it’s time to set the record straight, or at the very least give you my opinion on the newer chipsets being used in current GPS receivers.
First some background — up until couple of years ago, the SiRFstar III chipset was the gold standard for GPS receivers. Before this chip, reception in mountainous terrain and in other challenging conditions was often hit or miss. Manufacturers had to use the SiRFstar III or risk being ignored by the market. Then a patent dispute with Broadcom was settled, and not in SiRF’s favor either. Manufacturers began looking for high-sensitivity chipset alternatives, usually turning to MediaTek or STMicroelectronics.
But are these new chips as good as the SiRF III? My take is basically yes. All high-sensitivity chipsets can pull in weaker satellite signals, which means shorter time to first fix and an improved ability to hold the satellite lock in difficult environments, but this can also result in more multipath reception errors. The firmware for these new chipsets was far from mature when first introduced; it is much more difficult to fine tune firmware for high-sensitivity chipsets. IMHO, with succeeding generations of firmware, units with the new chipsets are now nearly as good as SiRFstar III models, with some of the remaining minor differences coming from the lack of a quad-helix antenna on most new models.
I still use my 60CSx for comparison testing, but lately the differences have been quite small and often difficult to discern. YMMV, but I’ll take the new interfaces and capabilities over earlier-generation models any day.