GNSS U-Blox M9N - Upgrade

warcelo · Dec 17, 2020

Hello, guys

This is my first post.
I'm an EE and I work with U-Blox on a daily basis, mostly with WiFi modules (NINA).
My Solo has the rev A GNSS board and it takes time to acquire the satellites, I'm going to update the module only, not buy these 3rd party entire boards, I can get samples from U-Blox for free and they are only $25 on DigiKey if anyone wants to update as well.
I haven't seen anyone using a M9N that is much more precise than the M8N at the cost of higher power consumption (negligent on a drone).
From my research and a quick talk with a U-Blox FAE the modules are pin to pin compatible and the protocol is the same, the M9N should be backwards compatible with the 7 and 8.
My question is: Have anyone tried this? My samples are on the way and I will try and let the community know.
Another question: Does anyone know what is the difference between Rev A and B?

I also found out that there are newer and better taoglas antennas like the HP5010A

HP5010A – GPS L1/L2/L5, GLONASS & BeiDou Single Feed, Stacked Terrablast Patch

The HP5010A GPS Receiver operates on GPS L1, L2, and L5 bands, GLONASS, Galileo, and BeiDou with a single feed patch assembly. It features a right-hand circularly polarized patches made of ultra-impact-resistant Terrablast material.

www.taoglas.com

Comments and suggestions are welcome!

warcelo · Dec 21, 2020

yarrr · Dec 21, 2020

warcelo said:
Hello, guys

This is my first post.
I'm an EE and I work with U-Blox on a daily basis, mostly with WiFi modules (NINA).
My Solo has the rev A GNSS board and it takes time to acquire the satellites, I'm going to update the module only, not buy these 3rd party entire boards, I can get samples from U-Blox for free and they are only $25 on DigiKey if anyone wants to update as well.
I haven't seen anyone using a M9N that is much more precise than the M8N at the cost of higher power consumption (negligent on a drone).
From my research and a quick talk with a U-Blox FAE the modules are pin to pin compatible and the protocol is the same, the M9N should be backwards compatible with the 7 and 8.
My question is: Have anyone tried this? My samples are on the way and I will try and let the community know.
Another question: Does anyone know what is the difference between Rev A and B?

I also found out that there are newer and better taoglas antennas like the HP5010A

HP5010A – GPS L1/L2/L5, GLONASS & BeiDou Single Feed, Stacked Terrablast Patch

The HP5010A GPS Receiver operates on GPS L1, L2, and L5 bands, GLONASS, Galileo, and BeiDou with a single feed patch assembly. It features a right-hand circularly polarized patches made of ultra-impact-resistant Terrablast material.

www.taoglas.com

Comments and suggestions are welcome!

What are you trying to accomplish with the M9N? It is marginally better accuracy than the Neo7 from the 3dr stock module, but isn't "high accuracy" like a RTK/PPK chip. Just curious what use case you would be trying to improve. I don't recall offhand what the difference between Rev A and Rev B was, but B was substantially better, and it was discussed at length on these forums. The various M8N replacements (like mRo) are great too.

I would be extremely interested in a ZED-F9P module that was drop-in compatible with Solo, especially with a small patch antenna like you linked. Drotek did this with the M8P, but being single frequency was frustrating to say the least.

RichWest · Dec 21, 2020

warcelo said:
Does anyone know what is the difference between Rev A and B?

REV A - Poor shielding and poor battery charge...if idle for a week, Solo would need to update constellation. Was a time sucker, 10 minutes maybe. 3DR had to make an improved copper shield to reduce the interference of near electronics.
REV B - Resolved both Rev A's issues. limited distribution or too late to the party...

mRo makes a drop in ready GPS for Solo, the best fitted GPS option available. What it should have been from the beginning...

warcelo · Dec 22, 2020

@RichWest Thanks for the info, I can shield the antenna passives on my board as well.
mRo is a solution but my idea is to make a better one, mRo uses the M8N and I want to use the M9N along with a batter antenna.
M9N is a little better than the M8N but significantly better than the M7N.

yarrr · Dec 22, 2020

warcelo said:
M9N is a little better than the M8N but significantly better than the M7N.
[/QUOTE]

It still seems like you'd be dealing with a lot of effort for a very marginal increase in performance by using the M9N.

I understand that more channels (and more constellations) is "better", but why do you need 2.0m position accuracy rather than 2.5m accuracy? The acquisition time essentially the same, and while you could have a higher update rate with the M9N, the aforementioned accuracy doesn't seem to justify a higher sample rate.

Again- just trying to understand what you're looking to do. I've had some multipoint cable cam flights around trees that I would appreciate having a higher accuracy postion, and use the Solo for mapping. But in both cases, the M9N would not provide a noticeable improvement whatsoever.

https://www.u-blox.com/sites/default/files/NEO-M9N_DataSheet_%28UBX-19014285%29.pdf

https://www.u-blox.com/sites/default/files/NEO-M8-FW3_DataSheet_%28UBX-15031086%29.pdf

https://www.u-blox.com/sites/default/files/products/documents/NEO-7_DataSheet_%28UBX-13003830%29.pdf