- Physical disassembly performed on a batch of first-generation 5G smartphones from six different OEMs to uncover core 5G electronic and RF designs
- Commonalities were identified from these initial 5G designs and characterized with simplified functional block diagrams
- Information gleaned from existing 5G designs will help to inform on the direction of future 5G smartphones designs
- In 5G, unlike in earlier wireless generations, modem and RF Front-End integrations are significantly more critical to the success of 5G devices
The market availability of 5G smartphones at this early stage of a new wireless technology transition has been unprecedented for the industry. Unlike the previous 4G LTE evolution, more handset vendors are making new devices available on day-one to consumers. Not only were the critical modem chipsets and RF Front End (RFFE) components made available earlier in the design cycle to smartphone OEMs but much of those solutions are of a complete “Modem-to-Antenna” designs which further help to accelerate time-to-market of these first-generation 5G smartphones.
In this paper, we will look more closely at the enabling RF technologies and components that are allowing for 5G devices to be made availability so early in the 5G network life cycle. As part of IHS Markit Technology’s “early-look” into both 5G network and device performance, we have evaluated at least six early 5G smartphones and performed thorough teardowns analysis to identify the core 5G wireless components and system design. This early batch of 5G smartphones includes smartphones from Samsung, LG, Xiaomi, Oppo, OnePlus and Huawei.
Fig. 1 – Early 5G smartphone samples used in teardown analysis
Diving deep into the fundamental 5G designs of these early smartphones, we began to identify the key components and vendors selection of 5G modems and the RFFEs. Of the six OEM brands under evaluation, the vast majority [5 out of 6] of the 5G designs sampled were supplied by Qualcomm while one variant of the Samsung Galaxy S10+ 5G contained an Exynos (Samsung LSI) solution and another model from Huawei use their internally developed modem solution (HiSilicon Balong 5000). These two “captive” modem suppliers are usually the exception to the rule or norms of the industry. Creating modems and RFFE requires a significant investment of resources. Clearly, with the impressive scale and scope of both Samsung and Huawei, these rarified OEMs can afford to invest in vertically integration of their 5G designs.
On the merchant side of the 5G ecosystem, Qualcomm stands alone with their Snapdragon X50 modem which was first announced back in 2016. To date, there are no other merchant modem supplier that has 5G modems built into smartphones. Both MediaTek and UNISoC (Spreadtrum) has announced their first 5G chipsets but has not been designed into smartphones by any known OEM. Also, of note, Intel recently sold their smartphone modem division to Apple (who was the sole customer of Intel’s 4G LTE modems) reducing the field of merchant modem suppliers down to just three players.
As the smartphone industry matures and consolidates, only OEMs with the scale of Apple, Samsung and Huawei (big-three) can afford to invest R&D dollars to create their own chipsets. The remainder of the market, including some big players like Xiaomi, Oppo and Vivo, all draw from merchant modem vendors and proven RF designs. With Qualcomm’s early leadership in 5G, these smartphone OEMs can better compete with the big-three with a proven commercial 5G solution from Qualcomm. This sourcing strategy allows those OEMs to focus on product innovation and market differentiation rather than spending resources investing in core 5G modem and RFFE technology.
Path to 5G is paved with discrete parts and increasingly tight RFFE coupling
Just as with 4G nearly a decade ago, where LTE connectivity was built atop of existing 3G technology, early 5G capabilities are consequently added to existing LTE designs through a discrete chipset fashion. This meant that 5G components were essentially bolted onto the smartphone design as opposed to being baked into the core chipset. This not only facilitated in the time-to-market of smartphones but also de-risked the development by reusing existing proven designs.
The block diagrams below illustrate the observed core electronic designs from modem to antenna, drawing commonalities between the six 5G smartphones IHS Markit has evaluated for this paper:
Fig. 2 – First-generation 5G design using discrete 5G modem and RFFE
Fig. 3 – Millimeter Wave version of first-generation 5G smartphones using highly integrated RFFE antenna modules
From the two block diagrams illustrated above, we can deduce that first-generation designs are additive in nature. There are discrete 5G components such as the single-mode 5G modem, 5G RF transceiver, and single-band 5G RFFE which are separate from the existing LTE RF chain. This initial 5G modem designs also require supporting parts such as SDRAM and PMICs which are often duplicated in the LTE portions of the smartphone. By building upon mature existing 4G designs, OEMs augment 4G capability with the new 5G standard. Often, time-to-market requirements of OEMs and operators (fear of not being first) are reflected in device design and in this case, early 5G smartphones contain additional components that otherwise would not exist in mature smartphone designs. Of the six initial 5G smartphones we have analyzed; five of the six devices have an architecture that resembles this first-generation 5G design. We discovered Qualcomm’s Snapdragon X50 5G modem in all but the international version of the Samsung Galaxy S10+ which uses Samsung’s Exynos 5100 5G chipset. Likewise, the 5G RFFE was primarily supplied by Qualcomm in all instances indicating the close coupling of modem and RF front end in 5G communication design.
Further, a separate version of Sub 6GHz 5G RFFE and millimeter wave (mmWave) 5G variants had been created for first-generation 5G RFFE designs. Due to the size, power and beam forming/tracking requirements of mmWave 5G, a highly integrated mmWave antenna (multiple) modules must be used. These modularized antennae contain every RF component starting with the transceiver all the way to the physical antenna. Currently, the only mmWave solution available on the market comes from Qualcomm. Therefore, the mmWave 5G design is offered as a complete modem-to-antenna solution. All other competitive modem vendors are still in the early stages of mmWave development [save Intel who has dropped out of the market supplying the smartphone industry]. Of the six OEMs evaluated here, both Samsung and LG have mmWave variants of their 5G smartphones to support US carriers deploying mmWave 5G such as AT&T, T-Mobile and Verizon using the Qualcomm solution.
Second-generation 5G modem Design
One of the biggest observations of first-generation 5G modem is the lack of multimode capability, hence a separate LTE modem is required [as described earlier]. As the industry matures, the second generation 5G modems will be defined by its multimode capability, integrating both LTE and 5G together onto a single chip. This evolution of core smartphone electronic design is necessary to reduce not just the physical footprint but also power requirements and manufacturing costs of 5G smartphones. Of the six 5G smartphones reviewed, only the Huawei is employing a multimode modem design with their first 5G chipset (Balong 5000). While this design helps to reduce the need for a separate 4G/3G/2G modem, our teardown revealed that other design choices made on the Huawei Mate 20X were far from ideal highlighting the challenges of early 5G technology.
Other modem manufacturers who have announced second-generation modems are Qualcomm with the Snapdragon X55 and Intel with their XMM8160. Realistically, we will only see the adoption of the Qualcomm solution given the recent market exit from Intel. In fact, at the time of publication, there are multiple designs with Snapdragon X55 being readied for late-2019 launch in the development pipeline.
The block diagram (Figure 4) illustrates the architecture of the Huawei Mate 20X 5G smartphone. While the Huawei is employing the only multimode 5G modem of the bunch, it is doing so with many design compromises. Firstly, the Mate 20X is also designed with a HiSilicon Kirin 980 SoC which already has an on-board LTE modem. Moreover, in operation, only the multimode Balong 5000 modem is used for 5G/4G/3G/2G communication, leaving the integrated modem in the Kirin SoC unused and arguably unnecessary. A better solution would be to use an applications processor (without modem) in place of the Kirin 980 in order to reduce cost, power and PCB footprint.
Furthermore, the Huawei Mate 20X 5G implemented a significantly denser supporting SDRAM for the Balong 5000. Whereas typical discrete modems are packaged with SDRAM chips that are measured in hundreds of megabytes (MB) in density, the Huawei Mate 20X design packs a surprisingly large 3GB of LPDDR4 in a package-on-package configuration (a full order of magnitude denser) which would rival most smartphone’s primary SoC SDRAM configuration. Looking at the silicon level, the 7nm Balong die size was found to be 50% larger than the Qualcomm X50 @ 10nm (findings collected in this batch of 5G smartphones). Of course, this is not an apples-to-apples comparison since one is multimode and the other single-mode and both manufactured on different fabrication nodes, but it illustrates the design compromise taken by different OEMs to enable 5G. A better comparison to the Balong 5000 would be the upcoming Qualcomm X55 5G modem. Both the X55 and Balong are multimode 5G modems and with the X55 manufactured on 7nm, we can deduce that the die size will also be comparably smaller than the Balong 5000.
The design efficiencies that are afforded in the Huawei Mate 20X design is the simplification of the RFFE (from the transceiver to antenna). As opposed to the dual radio chain of first-generation designs, only one radio path is required for 5G/4G/3G/2G since all wireless communication standards go through the single multimode modem and RF transceiver path [instead of two].
Huawei’s 5G design is currently limited to sub 6 GHz RF capabilities (which is the most common spectrum used so far 5G deployed internationally). For high performance mmWave support, Huawei has yet to come to market with a viable RFFE solution. This means that for carriers and OEMs supporting mmWave 5G networks deployment right now, the only choice available is Qualcomm’s highly-integrated mmWave modem-to-antenna design
Fig. 4 – Schematic of 5G design in the Huawei Mate 20X
The Huawei Mate 20X design highlights some of the challenges for OEMs in 5G modem design, balancing feature requirements, electronic design and costs. If the HiSilicon Balong 5000 modem were to be made available for other OEMs, and in direct competition with merchant modem providers, this early design benchmark would indicate that the Huawei design is not as competitive in terms of cost, board area utilized as well as power-efficient. However, given the “captive” nature of the Huawei design, these concerns are secondary to being able to bring a functional 5G smartphone to market on time. Also, since HiSilicon is a “captive” vendor, there are also less demands from OEM customers for more design efficiencies resulting in an arguably sub-optimal first-generation design.
Optimizing future 5G designs
This early analysis of initial 5G smartphones ultimately point us to the direction of 5G design evolution in future products. Just as multimode modems will be introduced in second-generation designs, bringing a single-modem and more tightly integrated RFFE design, the industry will look forward to further optimization of core electronic design as 5G technology matures.
What will we observe in future 5G designs? Following the evolutionary path of LTE modems nearly a decade ago (Fig. 5), we will see the integration of the multimode 5G modem into the smartphone SoC itself in the next iterations of 5G smartphone designs in 2020. This higher level of integration will leverage the existing SDRAM and PMIC supporting the SoC and eliminate another chipset on the motherboard and, more significantly, Bill of Materials (BOM) costs.
Further, we will see a highly integrated and cohesive RFFE architecture that supports both Sub 6GHz and mmWave 5G in one device. Just as premium LTE smartphones on the market today have RF support for global roaming, future 5G smartphones will integrate additional 5G frequency support and modes into a cohesive modem-to-antenna design. The need for cohesiveness or optimization of modem-to-antenna design is crucial in 5G applications where any signal degradation would result in noticeable lags or delays for the user. In summary; better, cheaper and faster 5G smartphones are on the horizon.
Fig. 5 – Future 5G design
Component maturation is a cycle that every new wireless standard progress through. Early LTE designs were as complex as the first-generation 5G designs we’ve identified in this paper. With advances coming in semiconductor manufacturing and the progression of tighter silicon integration, in particular the tight coupling of modem and the RFFE, the industry will begin to realize the benefits of maturing 5G chipset designs. Also, as we anticipate the forecasted smartphone design transition from LTE to 5G, the growth in manufacturing volume will inevitably drive down the overall cost of 5G devices. These benefits will ultimately flow down to the end consumer in terms of affordability and capabilities of future smartphones coming as soon as next year.