A new term started creeping up in manufacturers' phone specs listing, making a cameo way back with the
but still not as widespread as we'd like. Xiaomi even came out with the video you see above to brag about its virtues.
The feature is marked in a specs sheet as dual-frequency GNSS (Global Navigation Satellite Systems), often with "L1+L5" posted after it, as these are the two bands of the US Global Positioning System (GPS) that it works on.
It simply means that instead of receiving signal from a particular satellite on one frequency, the chip inside the phone in question is capable of doing it on two. Here are the purported benefits:
One frequency is used for locking the satellite, the other for positioning
- More accurate, lane-level positioning
The difference between knowing on which road are you driving, and in which lane on that road, or 1ft (30cm) vs 16ft (5m) accuracy
- Better city landscape and indoor positioning
New York skyscrapers are notorious for causing signal reflection and multipath errors that can be mitigated with dual-frequency GPS positioning
Does my Android phone have dual-frequency GPS?
While many phone makers started putting the Broadcom BCM47755 chip that supports this feature, and Qualcomm lists it in Snapdragon 855's chipset virtues, it is not an option that is unlocked even on phones with the necessary hardware. How can you check? Easy, just download GPSTest
from the Play Store and if you see L5 or E5a in the CF column (carrier frequency), you are golden.
Dual-frequency GNSS chips like the Broadcom 47755 can lock two signals from one satellite
The app can track the main GNSS constellations: GPS (denoted by an American flag), Galileo (EU flag), GLONASS (Russian flag) and Beidou (Chinese flag). It also shows regional satellite-based augmentation systems (SBAS), including QZSS (Japanese flag), GAGAN (Indian flag), ANIK F1 flag (Canadian flag), Galaxy 15 (American flag), Inmarsat 3-F2 and 4-F3 (UK flag), SES-5 (Luxembourg flag), and Astra 5B (Luxembourg flag).
Notice the L5 and E5a locks in the top row? These are the dual-frequency OnePlus 7 Pro, P30 Pro, Oppo Reno 10x, Honor 20 Pro, followed by single-frequency Galaxy S10+, LG G8, iPhone XR and Pixel 3 at the bottom
As you can see above, the phones on top - OnePlus 7 Pro
, P30 Pro
, Oppo Reno 10x Zoom
, and Honor 20 Pro
, have dual-frequency enabled, while the ones below - Galaxy S10+
, LG G8, and the Pixel 3
, do not. Mum's the word on the iPhone's situation, though, as there is no corresponding app for iOS.
The European Union can't shut up about its own Galileo system, going to great lengths to extol its virtues with fun little promos like the video below. According to the creator of the GPSTest app Dr. Barbeau
, however, in the US there will be no European satellites listed, even if the chipset supports multi-GNSS constellations and can take in Galileo signals, like the 855.
Does it work better? S10+ vs 7 Pro vs iPhone XR GPS accuracy test
The answer is, it depends on the chipset. While some of the phones with Snapdragon 855 here have their dual-frequency GNSS abilities enabled - the OnePlus 7
Pro and Oppo Reno 10x - they don't necessarily show better accuracy than, say, the Pixel 3 with Snapdragon 845, or the LG G8 with Snapdragon 855 itself.
Interestingly enough, all the phones we have in the office that showed dual-frequency as enabled, are Chinese brands, including the OnePlus 7 Pro, even though it carries a Snapdragon 855 chipset. Our 7 Pro is the model approved for sales in Europe, though, so the FCC review process could be in play here as well.
The GPS Test app
that we used is most likely not really optimized to utilize these capabilities and yet it managed to show that some dual-frequency devices, like the ones with Huawei's Kirin 980 chipset, are capable of following almost all satellites they saw in the more challenging indoor scenario. They also show the highest location accuracy of 13 feet - the second at the top P30 Pro, and the fourth Honor 20
Next is the third one at the top - the Oppo Reno with Snapdragon 855, while the other dual-frequency champ with the same chipset - OnePlus 7 Pro - didn't show better results than, say, the LG G8 which is second in the bottom row. The Exynos chipset on the S10+ showed markedly worse accuracy indoors, while the iPhone XR's vertical accuracy was on par with the Reno.
Top row from the left - dual-frequency OnePlus 7 Pro, P30 Pro, Oppo Reno 10x, Honor 20 Pro, followed by single-frequency Galaxy S10+, LG G8, iPhone XR and Pixel 3 at the bottom row
We are only showing the indoor test, as outside all phones performed great with a very similar location accuracy under the clear sky. What the indoor positioning probe demonstrates, however imprecise, is that some dual-frequency location hardware can indeed perform better with weaker signal and more interference from buildings.
That is to say in an urban environment, such as among Manhattan's skyscrapers, and that's all we could ask for. Now hurry up and unleash the dual-headed dragon on all phones already!