Help with using GPS-RTK Dead Reckoning pHAT (ZED-F9R, SKU GPS-21305) on a Jetson AGX Orin 64GB over the 40-pin header

GPS/GNSS Development Boards
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Using GPS-RTK Dead Reckoning pHAT (ZED-F9R, SKU GPS-21305) on a Jetson AGX Orin 64GB over the 40-pin header. Serial data is coming through fine, and we plan to mount it in a vehicle for position, speed and heading. I am reaching out for your support with the following:

1. Antenna: we have the board only. Which multi-band antenna do you recommend for it? We understand it needs to cover L1 and L2 and be mounted on a car/truck. What adapter cable do we need from the board’s u.FL connector? Are there cable-length or antenna-power limits we should keep in mind?

2. Firmware: the module reports HPS 1.00 (protocol 33.00) in UBX-MON-VER, but the u-blox interface description we have is for HPS 1.30. Can this unit be upgraded to HPS 1.30, and where do we get the image? If not, where can we find the HPS 1.00 interface description?

3. Dead reckoning without wheel speed: how much does automotive accuracy degrade with no odometer input? If we feed vehicle speed from the car’s OBD port instead, what update rate does it need?

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Welcome!

Antenna: For ease of install, the u-blox magnetic mount all band or L1/L2 will work great.

Firmware: Yes, the firmware can be upgraded using u-center. The latest firmware for the ZED-F9R is HPG 1.40 and is available from u-blox here.

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Dead reckoning without wheel ticks - It will obviously not be as good, but u-blox is really the only folks that can quantify ‘how much worse’. I don’t think vehicle speed is really the metric the F9R engine needs - wheel ticks allow for much more granular locating that the algorithm needs for fusion with the IMU. If you do find an answer from u-blox or a whitepaper, please post back here so we can all benefit from it.