Real world test of L1C

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I just bought a Poco X7 Pro. It promise to have L1C B1C support and dual band L5 too (Mediatek dimensty 8400)

So I made a quick comparison to my dual band Qualcomm snapdragon 870 phone.

I circled a round shape track 10 times. Poco X7 Pro reproduce the track 6 out of 10 times. With a shape that recognizable as a circle. 

Snapdragon 870 reproduce 3 out of 10. Among the 7 times it created drastically different track and very irregular shapes (twisted oval shaped)

I knew it's a very old chipset and don't even support Beidou 3 (which is helpful improve PDOP). But I have a snapdragon 780G dual band phone too, I don't think support Beidou 3 itself improve accuracy like this far, I mean Mediatek 8400 chipset.

According to the map app it can show exactly the building block I'm standing in (indoor, through the window). While 870 can't get it right most of the time. 

I also heard B1C has two tracking mode, one is to treat it with old C/A code and only purpose is to reduce cost. Another is to match the modulation (TM-BOC) so receiver get actual improvement. I wonder what's happening next with this technology. So far Qualcomm never say they provide L1C and matched B1C tracking mode.

Because Mediatek 8400 is a relatively cheap SoC it's a good take to make these feature more accessible ( 9300 and 9400 already have it but the price gap is big

[ndo...@gmail.com]

GPS will not broadcast L1C from any satellite until the ground control software update (OCX) is in place.  The current ground control software (AEP) treats all Block III satellites (the only GPS satellites physically capable of L1C) as Block II-F due to the software's limitations.

Once OCX is successfully deployed, only Block III and newer satellites (Block III-F and beyond) will broadcast L1C.

In the current constellation, Block III satellites account for 8 of 31 satellites.  1 more will launch by end of 2025, and the last of the block will launch in early '26.  Block III-F's are scheduled to launch in '29.  There are currently 11 Block II-F satellites.