Monday, September 3, 2018

[UPDATED] Pixel 3 XL projects out to be mid band LTE powerhouse

Straight to the point, Pixel 3 XL lab test results show mid band RF power output that we rarely have seen from a handset during the LTE era.  Smaller sibling Pixel 3 does not reach quite the same RF power heights, though it holds minor advantages in some low band output.  And both 2018 Pixel handsets measurably outperform their Pixel predecessors of the past two years.

Pixel 3 XL (A4RG013C) and Pixel 3 (A4RG013A) authorization filings became available to the public at the FCC OET (Office of Engineering and Technology) database at the end of last week.

For the radiated power figures, caveats about lab testing versus real world capability and uplink versus downlink always apply.  But solid uplink ERP (Effective Radiated Power) or EIRP (Effective Isotropic Radiated Power) generally correlates with good overall RF transmission and reception.  Conversely, weak uplink output typically cannot be overcome for anything but middling to poor overall RF performance.

RF power figures below represent best averaged and rounded estimates of maximum uplink EIRP test results provided to the FCC OET in the authorization filings.  Or in the case of ERP low band test measurements, that ERP was converted manually to EIRP for level comparison purposes.

Before taking a look at the graphs, a standard baseline for good EIRP is 200 mW (milliwatt) or 23 dBm (decibels relative to one milliwatt).  This is the target conducted power -- the RF power generated before it reaches the antenna -- on most handsets for most bands.  Without delving into excessive explanation, if the 200 mW conducted power can be turned into 200 mW or greater radiated power by the antenna, then the antenna gain and design tend to be implemented well.  This is particularly important for mid band and high band, less so for low band, which can present a size challenge to antenna design in handheld devices.

First up, the star of this show, the Pixel 3 XL.  And it generates its massive mid band power from excellent antenna gain of +3.70 dBi (decibels relative to an isotropic antenna).  Band 41 -0.90 dBi antenna gain is less ideal, though HPUE target conducted power of 400 mW (or 26 dBm) makes up for some of that loss.  All figures depicted are for EIRP from the main antenna; the auxiliary antenna across the board is a lesser gain antenna.


Next is the Pixel 3, all figures again from its stronger main antenna.  Its mid band antenna gain of variably +0.30 dBi or +0.98 dBi is not quite so potent as that of its larger relative.  And some of Pixel 3's average to good power output comes from greater than 24 dBm low band conducted power, not from antenna gain.  However, band 5/26 has an ever so slightly above unity +0.03 dBi antenna gain, and that is good but rare to see any positive gain for low band.


Graphing just main antenna gain versus LTE band approximate center frequency for both Pixel 3 handsets, we can see visually that mid band positive antenna gain.  One theory is that the full glass, partial matte backplates on both 2018 Pixel 3 variants may be providing greater RF transparency -- as opposed to the partial glass, partial aluminum backplates on the 2016 and 2017 Pixel variants, a few of which we will offer up for comparison shortly.



Yes, as bases for comparison, take a look at those RF output figures from an LG manufactured Pixel 2 and HTC manufactured Pixel that have preceded this Google in house designed 2018 Pixel generation.  In these instances, both are XL variants.  To summarize, the 2017 LG Pixel 2 XL and 2016 HTC Pixel XL frequently fail to hit the 200 mW baseline, though they are mostly consistent across the board and never woefully deficient.  The LG acquits itself better with band 4/66 and band 41, while the HTC just seems to continue the company's passably average RF performance on LTE.  As an aside, the Pixel 2 XL measurements follow a Class II Permissive Change authorization filing that preceded the handset release and did adjust some uplink power output.  Thus, upcoming RF tweaks to one or both of this year's Pixel duo still are possible prior to street date.



Finally, to expand the scope outside the Pixel universe, Samsung Galaxy S9 is the current handset to which both 2018 Pixel handsets are most likely to be compared.  Anecdotally, Galaxy S9 has been said to be a good RF performer.  RF numbers wise, Pixel 3 and Galaxy S9 are quite similar, the biggest difference being band 41 HPUE in the latter.  As for Pixel 3 XL, its mid band output once more grabs the spotlight.  In that regard, Pixel 3 XL stacks up very well.


Field testing the latest Pixel pair in the hands of users and reviewers over the coming months will tell us more about real world performance, but as of now, the lab tested EIRP figures offer an auspicious peek at what project to be improved and flagship caliber RF.

Source: FCC OET

4 comments:

  1. Thanks for the information, this is pretty cool! I'd love to see details of the 5" Pixel 1 vs the 5" Pixel 2. I noticed a large reception improvement on B2/B4 when moving to the Pixel 2.

    Also, have you looked into the OnePlus 6 data? FCC ID 2ABZ2-A6003

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  2. Data is also available from https://fccid.io/A4R

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  3. Cant wait for the Samsung S10 report, this Pixel 3 sucks for $800 7 the XL notch, hard pass
    Love your work though!

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