GNSS GPS Breakout ZED-F9P-05B

GNSS GPS Breakout ZED-F9P is a high-precision GPS module built around u-blox's F9 receiver. Regular GPS gets you within a few meters of your real position. This module uses RTK, a correction technique that compares its signal against a nearby reference station, to narrow that down to about a centimeter. It also tracks four satellite systems at once (GPS, GLONASS, Galileo, and BeiDou), which helps it get a fix faster and hold it in places where buildings or trees block part of the sky.

You can connect it over UART, I2C, or SPI, picked with the JP1 jumper. Over I2C it uses a fixed address of 0x42, so you'll need an I2C multiplexer if you want to run more than one on the same bus. It also supports "moving base" mode, where two of these modules track their position relative to each other even while both are moving, useful for things like measuring the heading of a moving vehicle or robot. A Soldered Arduino library is available to read positioning data directly.

A dedicated pin outputs a precise once-per-second timing pulse, and separate pins show geofence and RTK status at a glance. The board runs on 2.7 to 3.6V and measures 55 x 39 mm, with two mounting holes sized for M3 screws. If you want to save power, individual jumpers let you turn off the power, timing, RTK, and geofence status LEDs.