Connect (X)

Tag Archives: Massive MIMO

Opinion: Is Open RAN Hype Following That of 5G?

By Ernest Worthman

Like 5G, O-RAN is being positioned as the pièce de résistance platform for the next generation of hardware for the RAN. And there certainly seems to be a ration of organizations hopping on the O-RAN bandwagon, especially of late.

Brushing aside the hype, O-RAN is an attractive solution to the daunting challenge faced by 5G and wireless networks in general. However, using my favorite meme, all that glitters is not gold, has some applicability to the state of O-RAN.

Before we drill down on this, just for the fun of it, let us do a quick review of O-RAN. The particular definition varies slightly from organizations like the O-RAN alliance to major players involved in it (like Nokia). However, no matter how you slice and dice it, O-RAN is all about disaggregation of the RAN and open architecture. By doing that it offers an environment for any piece of O-RAN-compliant hardware to work with any other piece of O-RAN hardware – that is the bottom line.

One would think that would get everyone on board. However, there is so much more to this beyond the technology. The situation is not unique to O-RAN. Similar situations exist with openAI, various compute platforms, and dozens of others. Even elements that have achieved accepted open status, Unix for example, are not necessarily the de facto go-to for everything and everyone. However, with 5G it would definitely be smart for everyone to be on a common hardware platform, open or otherwise. And, in a perfect world, open hardware would be the best solution.

There are a lot of places where open standards exist and work well. Car parts are an excellent example. With tires, a certain size tire, regardless of who makes it will fit any vehicle that can run that size. Other parts, alternators, belts, batteries, etc. as well. If a battery is specified as a certain group, no matter who makes it, it will fit the particular vehicle that uses that group.

The same should be true for O-RAN. With O-RAN the focus is on its three main building blocks – the radio unit (RU), the distributed unit (DU), and the centralized unit (CU). The idea being that any manufacture’s O-RAN RU will work in another manufacturer’s DU, or CU O-RAN, system that complies with the O-RAN standard. There are other layers, of course, but these are the critical ones.

Open hardware systems bring to the table more competition, better designs, lowered CAPEX, and user benefits such as adding features, increasing deployment flexibility, capacity scaling, and upgrading components. As well new services, such as AI layers and virtualization are easier to integrate.

However, proponents of the other camp, proprietary hardware, take some pretty strong positions and present similarly strong arguments. Proprietary hardware has better profitability because there is less competition. There is also the question of reliability across multiple vendors.

Proprietary hardware locks in a particular vendor – job security if you will. Deals are made, hardware is locked in and the marriage between the vendor and user is inked. It provides a known supply chain, service sector, and responsibility platforms. It is a mature model and is very well understood and has been accepted since the beginning of wireless time.

Proprietary hardware is always more expensive than open hardware. Tertiary elements such as service, parts, warranties, and the like are locked in as well. Simply put, because proprietary hardware is more profitable than open hardware, vendors find the proprietary model much more desirable.

With open hardware, much of this becomes a free-for-all. For example, who will service the equipment? If a third party is involved in service and something goes wrong, there is often a lot of finger-pointing that happens. And who do you hold responsible when something goes wrong? The vendor? The servicer? Or do you simply self-service and fight with the vendor whether it was their equipment or some other cause.

What about longevity? Say a particular vendor goes out of business and its hardware is no longer available. The user is stuck with replacing that particular hardware with someone else’s proprietary hardware. That can be a nightmare. And, quite honestly, vendors like being locked in. Users, not so much.

There are also the issues of stability, capacity, and scalability. These have been challenging to all open platforms since the idea evolved. Some, such as computer software and hardware have conquered these, but it takes time and the more complex the platform is (such as O-RAN and openAI) the longer it takes to achieve stability. And even mature open platforms continue to have occasional (some regular) burps.

Next, there are peripheral components. AI is set to play a huge role in wireless. It is critical that AI understand the complexities that accompany 5G – ultra-reliable low-latency communications (URLLC), dynamic spectrum sharing (DSS), Massive MIMO, dynamic and intelligent, software-driven spectrum allocation, virtualization, software-defined networks (SDN) and many of the other new characteristics of 5G.

The use of AI in the RAN presents the same challenges as with other domains. AI has natural biases due to the way algorithms function. By nature, it has errors and dependencies. It is more visible in platforms such as facial recognition, but it also exists in stock analysis, hiring, employment, and others. There is no reason not to assume it will have similar issues in the RAN.

And, of course, let us not forget security. The more open the interface the more difficult security becomes and the larger the threat surface. Add to that the eventual massive deployment surface of this platform and its tangential vectors (Internet of Anything/Everything (IoX), for example),and it certainly becomes critical.

Also, in the 5G space, strict latency requirements, for example, are added to the queue. That requires similarly strict encryption requirements (that is a very interesting discussion but too lengthy for this column). And, with the tens and eventually, hundreds of billions of devices expected on networks as 5G matures, keeping rogue devices and bad actors at bay will be challenging.

So, what else is holding up the rapid deployment of O-RAN, which will be essential for 5G?  The technical issues remain quite challenging regardless of how rah-rah some proponents of it, are. Some even claim it will never happen. But there are other issues as well.

But, all of that aside, just getting all the players on board will be tantamount to herding cats. There are a lot of different players with a variety of angles and getting everyone to agree is difficult. This is a cooperative environment. For the manufacture, open interfaces require best practices among ALL manufacture to ensure the integrity of the link – the play nice, everybody, scenario. And frankly, this is a big change to a very well entrenched and mature industry – resistance to change will be hard to overcome.

Beyond that, there is also the issue of retrofit. That is not a problem with the greenfield segment of 5G. However, in existing equipment that is a significant challenge.

A recent report from the Dell’Oro Group predicted that O-RAN will not account for more than 10 percent of the overall market by 2025. ABI Research does not expect the CAPEX of O-RAN hardware to surpass traditional RAN until close to the end of this decade.

In the end, and down the road, O-RAN will, most likely, get the issues ironed out and, unless an unknown platform suddenly emerges, become the standard hardware platform for 5G. The really tricky part is for 5G development to start buying into O-RAN, or at least prep for it, and not keep adding proprietary hardware just to get 5G out.

So, while the noise about O-RAN seems to be making it the answer to all of our deployment problems, that really is not the case. It has a bit of a haul in front of it.  But it is fun to follow the various threads.


Ernest Worthman is an executive editor with AGL Media Group, a senior member of IEEE and an adjunct professor at the CSU Walter Scott Jr. College of Engineering.

SmarTone, Ericsson Trial FDD Massive MIMO

By The Editors of AGL

Ericsson and SmarTone, a mobile network operator in Hong Kong, are trialing FDD Massive MIMO technology as part of the operator’s network evolution plan toward 5G.

The trial, involving FDD Massive MIMO on 1800 MHz, represents the first of its kind for operators in Hong Kong. It is proving the capabilities of this key technology ahead of the live deployment in 2018 of AIR 3246, Ericsson’s new radio that can support Massive MIMO over 4G/LTE with Ericsson’s 5G Massive MIMO Plug-In.

Massive MIMO is a key technology that bridges network evolution from 4G to 5G, adding intelligent capacity and boosting user experience, according to Ericsson. Massive MIMO on FDD yields a multi-fold increase of network capacity and increase user throughput by up to five times, boosting performance for end users.

Ericsson has recently launched its first radio, AIR 3246, supporting FDD Massive MIMO for both 4G and 5G. The technology enables operators to boost capacity in their LTE networks.

Sprint, Ericsson Go Massive MIMO at 2.5 GHz in First U.S. Field Tests

By The Editors of AGL

At Mobile World Congress Americas, Sprint and Ericsson announced the results of the first U.S. 2.5 GHz Massive MIMO (multiple input, multiple output) field tests conducted in Seattle, Washington and Plano, Texas using Sprint’s spectrum and Ericsson’s 64T64R (64 transmit, 64 receive) radios. The two companies are preparing for commercial deployment next year, with Massive MIMO radios capable of increasing Sprint’s network capacity up to ten times.

Dr. John Saw, Sprint CTO, said, “Massive MIMO is a tremendous competitive advantage for Sprint, enabling us to maximize our deep 2.5 GHz spectrum holdings.”

Testing of Massive MIMO on the Sprint LTE Plus network in downtown Seattle showed a capacity increase of approximately four times compared to an 8T8R antenna. To showcase this capacity, Sprint convened 100 people with Samsung Galaxy S7 phones and ran simultaneous file downloads on a timed-test on all networks. The testing showed a 100 percent success rate on the Massive MIMO-powered Sprint network.

In Plano, Texas, Sprint and Ericsson also recently tested Ericsson’s 64T64R Massive MIMO radios reaching peak speeds of more than 300 Mbps using a single 20 MHz channel of 2.5 GHz spectrum.

For both field trials, Ericsson provided the radio network infrastructure and backhaul equipment. Sprint and Ericsson together developed the test cases and requirements, which included a variety of performance scenarios involving multi-user and non-stationary testing. The Radio Network infrastructure included Ericsson’s next-generation 5G-ready AIR6468 radio, and the backhaul equipment utilized the MINI-LINK 6352 R2 microwave radios which can provide up to 10 Gbps of backhaul, future proofing the network for 5G.

Ericsson Quickens the Pace in the Race to 5G

By The Editors of AGL

Even though there is no standard yet, Ericsson announced that its platform now includes an FDD radio from capable of supporting 5G and Massive Multiple Input Multiple Output (Massive MIMO). The new radio will provide a bridge between fourth generation and fifth generation wireless using today’s spectrum allocations.

The AIR 3246 is designed to complement to Ericsson’s global 5G radio offering, supporting both 4G/LTE and 5G NR (New Radio) technologies. Operators will be able to bring 5G to subscribers using mid-band spectrum and boost capacity in their LTE networks.

Ericsson’s 5G Platform includes three previously launched time division duplex (TDD) radios capable of supporting 5G and Massive MIMO, as well as core, transport, digital support and security elements.

The radio will enhance 4G capacity for subscribers today and simplify the transition to 5G in the future, according to Fredrik Jejdling, head of Business Area Networks at Ericsson.

Stefan Pongratz, Senior Director at the Dell’Oro Group, said, “With an expected installed base of 10 million LTE macro radios in high traffic and metro areas by 2021, service providers are expected to capitalize on the improved spectral efficiency made possible with Massive MIMO.”

FDD Massive MIMO is part of a trial with T-Mobile US, on three sites in Baltimore, Maryland, which will be the first time that standardized Massive MIMO will be used to carry commercial LTE traffic using mid-band FDD spectrum.

Massive MIMO on FDD can increase network capacity up to three times and bring up to five times better user throughput, boosting performance for the end users. Today’s global base is primarily on FDD technology and devices, which separates uplink and downlink streams on different radio frequencies.

Commercially available in the second quarter 2018, AIR 3246 will be part of Ericsson Radio System.

Sprint, Samsung Test Massive MIMO in South Korea

June 21, 2017 —    

Using Massive MIMO Samsung radios, equipped with vertical and horizontal beam-forming technology, Sprint achieved peak speeds of 330 Mbps per channel using a 20-megahertz channel at 2.5 GHz during field trials in South Korea. Capacity per channel increased about four times, cell edge performance increased three times and overall coverage area improved as compared to current radios.

Günther Ottendorfer, chief operating officer – technology, at Sprint, said. “Massive MIMO is a tremendous differentiator for Sprint because it is easily deployed on 2.5 GHz spectrum due to the small form factor of the radios needed for a high frequency band. In lower frequency bands, wavelengths are much longer and therefore the radios require much larger, impractical form factors. This makes Massive MIMO an important tool for unleashing our deep 2.5 GHz spectrum holdings.”

The Massive MIMO radios use 128 antenna elements (64 transmit, 64 receive) compared with 16 elements 8T8R antennas 8T8R (8 transmit, 8 receive) radios currently deployed by Sprint across its U.S. network. The purpose of the test was to compare the performance of Massive MIMO radios with 8T8R radios. The testing included multi-user and mobile user cases. Samsung provided the Massive MIMO network infrastructure, as well as the test network design, operation, data collection and processing. Both companies will use the results in preparation for commercial deployment of Massive MIMO in the U.S. and other markets.

In cities across the U.S., Sprint plans to deploy Massive MIMO radios with 128 antenna elements using its 2.5 GHz spectrum. In March, Sprint deployed Gigabit Class LTE on a live commercial network in New Orleans. There Sprint used three-channel carrier aggregation and 60 megahertz of 2.5 GHz spectrum, in combination with 4X4 MIMO and 256-QAM higher order modulation, to achieve Category 16 LTE download data speeds on a TDD network. With Massive MIMO radios using 64T64R, Sprint has the ability to push capacity beyond 1 Gbps to reach 3-6 Gbps per sector.