5G is the technology evolution that everyone so anxiously awaits. As the fevered marketing pitches reach “I want to believe” levels, we must dig a bit to find “the truth is out there.” One thing of which we can be certain: since 5G will encompass 4G, Wi-Fi and the packet core, almost anything selling in 2020 will have a 5G label. Infrastructure vendors (and many mobile operators) seek 5G mmW in hopes of new revenues, some even planning 5G in lower bands, which will be LTE Evolved and backward compatible with LTE. It is the centimeter and millimeter wave spectrum where the exciting 5G use cases will land.
In a recent webinar, Making 5G mmWave a Commercial Reality In Your Smartphone, Qualcomm puts forward their progress on the 5G mmW device. Rich with information and insight, it is worth a look on the Qualcomm website (here). Here are some key takeaways and screen captures from the webinar.
5G New Radio Non-Standalone
5G NR (NSA) will anchor to the LTE network which provides the broadcast, paging, and fallback data functions. The 5G mmWave channel is a secondary data channel, much like one gets with LTE and Wi-Fi aggregation. Low-band connectivity is required for these reasons.
- 5G NR (NSA) simplifies 5G deployment and accelerates time to market.
- The Evolved LTE anchor reduces the added complexity and risk that will come with Stand Alone.
- Low Band connectivity will provide continuity when the mmW signal is blocked.
- Will (NSA) be good enough causing delays to Standalone (SA)?
- Will Gigabit LTE capture enough of the use cases causing the mmWave business case to struggle?
5G mmWave Outdoor Simulation
System coverage simulations are much better than they used to be, as one operator told me that 4×4 MIMO simulations were very close to what they see in deployment. Qualcomm showcased a 28 GHz deployment simulation for San Francisco at MWCA and included this slide in the webinar.
- Qualcomm states 28 GHz with 150m – 200m site-to-site spacing meets coverage needs.
- Site spacing here calculates to 167m based on 36 per sq km.
- Coverage shown is outdoor street level, a subtle suggestion of mmW building penetration challenges.
- Are there enough mmW outdoor mass market use cases for blanket coverage?
- Are hotspots and venues enough to make 5G mmW viable?
- Will outdoor 5G mobile usage resemble texting while walking?
- Will four operators deploy 4 x 36 = 144 gNodeB (gNB) access points per sq km?
- Will joint ventures deploy neutral-host mmW networks?
3D Beam Steering
Beam steering is essential for 5G mmW operation as the added gain and interference reduction with the radio energy focused into a beam is necessary to overcome the mmW propagation challenges. Qualcomm shows that beamforming from multiple gNBs and on handsets make the 150m – 200m gNB spacing feasible. Both the gNB and the device must find the best beam, direct or non-line-of-sight, in real time and rapidly switch from one beam to the next. Beam switching may also happen across different gNBs complicating matters as both the mobile and the network will operate in a closed loop manner to rapidly track the beams.
Here is a cropped screen capture from the webinar showing three 4×2 patch antennas, in a format about the size of an iPhone 6s.
- Mobile antennas are hard to get right, and with the hand and environment blocking the mmW, multiple sites on the device will have these patch antennas.
- Front and back, top and bottom placements pose additional challenges for handset designers.
- Will mmW lead to AntennaGate 2.0?
- How many antenna patches will be needed? Maybe 4?
- Will these antenna systems be practical for smaller form factors?
Integrated access and backhaul
This 3GPP-R15 study item will be useful when fiber optic backhaul is not available. Each gNB will have site-to-site beamforming using the same mmW spectrum for backhaul and access. With this technology, deployments of gNBs will become plug and play – only power is needed.
5G mmW will deploy with use cases that operators understand, namely Fixed Wireless Access (FWA) and enhanced Mobile Broadband (eMBB). A reasonably wide-ranging deployment will encourage 5G mmW mobile adoption and vice versa. Qualcomm and others have shown the technological barriers manageable. 5G mmW will deploy, but use cases other than mass market FWA or eMBB are TBD.
This Brainwave is from the Machinomics Research at SAR Insight and Consulting. Machinomics identifies and expounds on the game-changers as the Internet of Things evolves into the global Machine Economy, hence the name. Find out more about the new Machinomics (here) as we develop this service.