How can I update firmware for GPS receiver? There are some updates for ANTARIS at u-blox site . Can I use it?
No. There is no update later than 3.00. I don’t believe that the fw for a u-blox Antaris3-based module will work. What I know is that the GPS part is equiped with flash memory like the TIM-LP and can be configured with u-center from u-blox (on the external GPS port). To switch off WAAS/EGNOS is a good idea, and a static treshold (minimum speed for showing a movement in position) too, depending on your application.
Indeed, this will not work. The Antaris chipset inside the Q2501 is Antaris 2. On the other hand, Wavecom proposes a new offer, called C-GPS, that guarantees updates of the GPS stack, even through the DOTA feature.