The iPhone 11 Pro has much faster LTE performance than the regular iPhone 11, but both phones aren't much faster than last year's iPhones on three major US networks, according to our testing.

This comes as a big surprise to me. In theory, the Intel XMM7660 modem in the new iPhones should perform better than last year's models. But the Intel XMM7660's new capabilities are either blocked from use, or apply primarily to network features the carriers haven't widely installed yet.

I did see a huge difference within generations, though, as iPhones with 4x4 MIMO (the iPhone 11 Pro and iPhone XS) downloaded the pants off of iPhones with 2x2 MIMO (the iPhone 11 and iPhone XR).

You'll find a lot of iPhone reviews focused on the phones' cameras. As more people record, send, watch and share 4K video, LTE performance is critical. Many people just blame their carriers when they have bad LTE service. But that's only half the story. Your older phone may not be able to tap into most of your carrier's network, especially if you're using AT&T or T-Mobile.

In previous years, we've relied on lab tests to check the reception capabilities of iPhones. (See our reports on the iPhone XS Max, iPhone 8, and iPhone 7.) This year we decided to change things. I tested the iPhone 6, XR, XS Max, 11, 11 Pro Max, and a Samsung Galaxy Note 10+ in 10 different locations in Manhattan on AT&T, T-Mobile, and Verizon. (I had Sprint SIM cards as well, but they started freaking out with the amount of SIM-swapping I was doing, which was well beyond what any normal consumer would ever do. Possible kudos to Sprint for fraud prevention!)

This let me do same-time, same-place testing of multiple models. We also rely a lot on crowdsourced Ookla Speedtest Intelligence data, but the great mystery in crowdsourced data is whether different tests were done under different network conditions. That usually smooths out with very large data sets, which we'll probably have in a month or two from Speedtest. (Note: Ookla is owned by Ziff Davis, PCMag.com's parent company.)

AT&T is the fastest overall carrier for the new iPhones, as well our Fastest Mobile Network winner for 2019. But you'll need an iPhone XS, XS Max, 11 Pro, or 11 Pro Max to really feel the difference there.

3.5 Models of iPhone

There are three (and a half) models of each of the new iPhones, each with slightly different LTE capabilities, as I explain in this story. There's a US model, which includes bands and technologies for all the US and Canadian carriers (including GSM, CDMA, and LTE), but lacks key bands for Europe. There's a China model, with dual physical SIM card slots and probably some firmware alterations to adhere to Chinese political concerns. And there's a "rest of the world" model, which removes US frequency bands 14 and 71 (used by AT&T and T-Mobile) and replaces them with 11 and 21 (used in Japan), 28 (global), and 32 (Europe).

The iPhone 7 and 8 also had Qualcomm modem options, but their capabilities were limited to those of the Intel modems. The Intel XMM7560 modem is capable of 5xCA and the XMM7660 is capable of 7xCA, but the phones don't use those features.

The "half" model refers to how "rest of the world" phones sold in Japan have their CDMA radios activated through firmware, while that feature is left dormant in phones sold in other countries.

Apple has a full list of what bands it supports on each iPhone model on its site. The company doesn't specify why it wasn't able to build all of the bands into one model, but it's still common for phones to come in multiple models globally. For instance, there are three models of the Samsung Galaxy Note 10+, with similar differences to the iPhones. The problem may just have to do with how many antennas you can fit into a device.

All of this year's models, whether 11, Pro, or Pro Max, use the same Intel XMM7660 modem; their differences come in which frequency bands they support and whether they have 4x4 MIMO. The first bit affects what country your phone works well in; the second, as I'll explain, really increases speeds.

The modem, the little chip that connects your iPhone to the internet, has been the subject of major drama in recent years. For several years, Apple used modems from Qualcomm, widely acknowledged as the world's quality leader. Then it split the iPhone 7 and 8 generations across Qualcomm and Intel, got into a big spat with Qualcomm over licensing fees, and stopped using Qualcomm entirely last year. Finally, this year, the two companies made up and Apple agreed to buy Qualcomm modems again, for at least three years starting with the 2020 iPhone models. This is important because Qualcomm has the only 5G modems that work with AT&T and Verizon at the moment, and Apple has to launch a 5G iPhone in 2020 or get effectively shut out of Chinese carriers. Intel dropped out of the consumer modem business, Apple bought most of its assets, and most observers think Apple will have its own modems around 2023.

Intel's Promises Unrealized

As iPhone generations advanced, phones got faster through the use of carrier aggregation—bonding different channels of LTE spectrum together to form a wider road. But it looks like we've hit a momentary roadblock. (I'm going to use a common abbreviation a lot here —3xCA means three times carrier aggregation, in other words, bonding three channels of spectrum.)

The widest carrier of spectrum you can use in LTE is 20Mhz wide, although many of the channels used by US carriers are narrower, all the way down to 5MHz. (Narrower channels have lower speeds.)

Intel's XMM7660 modem in the new iPhones supposedly supports seven-carrier aggregation. But FCC filings, my own test results, and other sources show that the new iPhones only support 5xCA and a total of 100MHz spectrum usage. The latest Qualcomm-based Android phones, like the Samsung Galaxy Note 10+, support 7xCA.

This difference only shows up on AT&T right now. AT&T has an extremely fragmented spectrum setup, so it needs to combine six narrow licensed channels in some areas—6xCA. The Note 10+ can use that to its best extent. According to the FCC filing, iPhones can't.

We've seen this behavior from Apple before. The modem in the iPhone XR and XS Max, the Intel XMM7560, can support 5xCA. But tests showed the phones as only using 4xCA on licensed spectrum. (The phones may be able to add a fifth carrier in the few areas with LAA, a technology I explain below.) The modem in the iPhone 8 can support 4xCA, but in the US it cannot support four maximum-width channels. So while the iPhone 8 can use 80MHz of spectrum (4, 20-Mhz channels) in Australia, it can only support 60MHz of spectrum in the US.

The new iPhones support five-carrier combos that can be used by all the US carriers, although only AT&T regularly combines five channels of licensed spectrum. In the list below of the five-carrier combos that the iPhones support, anything with band 41 in it is for Sprint; anything with band 48 (CBRS) will be initially for Verizon, as I'll explain later; 2/5/66, 2/14/66, and anything with band 30 in it is for AT&T; and 2/12/66 will work on AT&T and T-Mobile.

All of the carriers except Sprint also mix in band 46, which is called LAA (licensed assisted access), and uses the same airwaves as 5GHz Wi-Fi. That isn't on the list because it's covered in a different part of the FCC application. LAA is only available in very limited, high-traffic areas, such as downtown centers, major tourist attractions and sports venues.

This FCC filing shows all the ways the new iPhones can combine five channels of licensed spectrum, without LAA.

The Biggest Difference Between iPhones

The biggest real-life difference, though, is in the use of 2x2 versus 4x4 MIMO. This increases the number of antennas used for more parallel streams of data. (MIMO stands for multiple in, multiple out.) 4x4 MIMO was introduced into the lineup with the XS and XS Max; it was not available on the X, the XR, or anything earlier.

The 4x4 MIMO-capable iPhones, the 11 Pro Max and XS Max, maxed out twice as fast on AT&T as the non-4x4-capable phones. It's clear that if you want high LTE speeds in 2019, on AT&T or T-Mobile at least, you need a 4x4 MIMO-capable phone.

According to this research, the XS generation had 4x4 MIMO on frequency bands 2, 4, 7, 25, 30, 41, and 66. The 11 Pro adds band 48, also known as CBRS, which hasn't been turned on yet and which I'll get to later.

The 11 Pro should be able to achieve higher speeds than the XS Max by using 4x4 MIMO on three carriers rather than two. That explains some of the theoretical speeds cited by Apple with both phones.

Apple and Intel promote the iPhone 11 Pro as having "1.6Gbps" LTE, but that's only possible in very limited circumstances right now. It takes three maximum-wdith, 20MHz channels of spectrum at 4x4 MIMO, and two 20Mhz channels with 2x2 MIMO. Nobody in the US currently has 100MHz of licensed LTE spectrum. That's mostly available where carriers have LAA installed—a system that uses the same airwaves as Wi-Fi to enhance LTE speeds, a trick introduced with the XS/XR generation. It will also be available with CBRS.

I didn't see the 11 Pro's five-carrier advantage bearing out in my real-world testing, but it's a capability carriers could put in place in the future.

Rather, the XS Max showed somewhat better average speeds overall than the 11 Pro. I think this is an anomaly that would smooth out with a larger data set, especially if I could have found somewhere with working LAA. I tried; the phone wouldn't attach to LAA even in some confirmed locations. This may be an early firmware issue. T-Mobile, for instance, can do two channels of licensed spectrum and three of LAA, which should have shown an advantage for this year's phones.

4x4 MIMO is not a panacea. Sometimes networks just act weirdly. I don't know why in this set of tests, the iPhone XR got higher maximum speeds on Verizon (remember, same time, same location) than the XS did. That shouldn't happen, but it did. This sort of network variability is why a lot of ordinary people think all phones perform the same on LTE, even though they don't.

Upgrade Your iPhone for Better Coverage

If you have an older iPhone, it's critically important that you upgrade for better coverage.

Last year's models were the first to support T-Mobile's new band 71 and AT&T's band 14, both low-frequency bands that help extend rural coverage and add speed over broad areas. While I wouldn't have seen big differences from bands 71 and 14 in my New York City tests, they'd make a much bigger difference outside the city.

There's a bit of a misconception (which I help spread, sometimes) that AT&T's band 14, aka FirstNet, is only usable by government employees. They get priority on the band, but if they aren't using it, anyone can—and most of the time, they aren't using it. So band 14 helps everyone.

The iPhone XR has bands 71 and 14, but the iPhone 8 and earlier don't—so if you're struggling with low signal on AT&T or T-Mobile on an iPhone 8 or earlier, getting an iPhone XR or newer will make a difference for you.

On Sprint and Verizon, upgrading is about speed rather than coverage. The new iPhones introduce HPUE (high power user equipment) for Sprint's band 41, which is the band you need to go from really slow to pretty fast. HPUE, which turns up the phone's transmit power, extends fast coverage by 24 percent, according to Sprint. No previous iPhone has this technology, although Android phones have had it for two years.

For Verizon, the new capability here is CBRS, which could make LTE speeds go through the roof, but...not yet.

What Is CBRS, Anyway?

On AT&T, T-Mobile, and Verizon, getting faster performance out of the iPhone 11 Pro and 11 Pro Max will rely on CBRS, a brand new frequency band that hasn't been turned on yet.

CBRS operates at 3.5GHz, a slightly higher frequency than existing US 4G networks. That frequency means it has relatively short range, and will be most appropriate for center cities and for large indoor setups like convention centers, stadiums, and casinos.

But CBRS is...weird. It's divided between a section that can be used by anyone, like Wi-Fi, and a section that will be licensed, like cellular. The Wi-Fi-like portion is now available to carriers; the licenses are going up for auction in June 2020, so any networks dependent on them likely won't appear until late next year.

Verizon is the most aggressive carrier on CBRS, saying it will deploy it in unlicensed spectrum soon. But the CBRS situation is so complicated, and Verizon's plans so small-scale, that I don't think it's going to make a noticeable difference for most users within the next 12 months. And at that point, we'll be getting the 5G iPhones.

How About 5G?

Apple will almost certainly introduce 5G iPhones next year based on an upcoming Qualcomm chipset it's going to announce in December. By next year, the Sprint/T-Mobile merger logjam will be broken and all of the networks will have greater 5G coverage as well.

5G will make a huge difference. Even if you ignore AT&T and Verizon's very limited coverage millimeter-wave areas, broad-coverage low-band 5G is coming next year. Low and mid-band 5G pretty much triples speeds on Sprint, and will probably increase speeds by at least 30 percent on other carriers.

That's a strong argument for sitting and waiting if your iPhone works just fine. I don't believe there's any virtue in suffering, and if you're struggling along with an iPhone 6 or lower that stalls out or barely connects to LTE, you shouldn't endure another year of frustration. But if you have an iPhone 7 or greater and you're basically satisfied with your speeds and coverage, I'd say wait for the 5G model, from a modem perspective.

This is a big reason why you need to replace your old iPhone. These tests were in the same place, against the same cell sites.

What This All Means

How important are mobile coverage and speeds to you? If one of these statements fits you, you should upgrade. Otherwise, sit tight and wait for 5G.

"I need the ultimate iPhone LTE speeds." Upgrade to the iPhone 11 Pro or 11 Pro Max for the 4x4 MIMO.

"My Sprint network barely works." Upgrade to the iPhone 11 or better for the HPUE.

"My AT&T/T-Mobile coverage is poor." Upgrade to the iPhone XR or better for the band 14/71 ability.

"I need the ultimate LTE speeds on AT&T, period." Ditch your iPhone and get a Samsung Galaxy Note 10 or S10.

"I have an iPhone 6 or earlier." Upgrade to the XR or better; performance will more than double.

There are other reasons to buy a new iPhone, of course—mostly the cameras. I'm just saying that if you have a new enough phone, LTE may not be one of the reasons.

Further Reading

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