Massive MIMO Rocks Back to Wirelessone.news
Dark blue: Building actively: China Mobile, Softbank Japan, Bharti India,
Jio India, Vodafone India, Singtel, Globe Phillippines
Dark green: Announced: DT, FT/Orange, BT, Sprint USA, Qatar, Verizon USA, T-Mobile Netherlands,
Light green: Talking: Vodafone England, Vodafone Turkey,
Safaricom Kenya, Telekom South Africa
- Published: 07 December 2018 07 December 2018
200 FDD Massive MIMO systems are on their way to True Thailand from Huawei. FDD has been in dozens of trials for two years, but this is the first announced deployment. British Telecom tells me their trial is going well; if that continues, they will deploy. This is important because most spectrum below 2300 MHz is FDD and currently carries most of the traffic. Tens of thousands of TDD Massive MIMO systems have shipped, most in the 2500 and 3500 MHz bands.
Huawei has tested the 32 antenna systems to 4.7 times the capacity of a two antenna system. T-Mobile expects actual performance in the field to be more likely 2-3X, especially to mobile phones. Ericsson's Kathy Egan in 2017 wrote me, "Capacity increase as compared to 2 transmit antennas is between 1,5x – 3x on average and 1,9x – 5x for cell edge." I don't believe they have announced substantial deployments, although several carriers are ready to go. Lund University notes line of sight performance is much better than NLOS.
- Published: 25 July 2018 25 July 2018
Massive MIMO produces a 2-7X capacity improvement, far more than the 15-50% of 5G NR software. Every engineer knows the 5G hype has become ridiculous, especially because Massive MIMO is a key component of 4G.
Guido Weissbrich of Vodafone Germany confirms they have moved from trials to deployment. His colleagues are in production in Australia. Bharti in India is covering much of Kolkata, formerly known as Calcutta. Verizon is widely deployed in the U.S. but has released few details.
All of these, I believe, are below 2.1 GHz and are FDD. One vendor off the record guessed FDD Massive would only be a 1.5X improvement. Karri Kuoppamaki of T-Mobile expects a 2-3X improvement.
- Published: 28 May 2018 28 May 2018
Karri Kuoppamaki tells me T-Mobile has major plans for Massive MIMO in frequencies below 2300 MHz, which are designated for FDD (Frequency Division Duplexing.) TDD Massive MIMO has been shipping by the tens of thousands since 2016, but FDD is still only in trials.
Massive MIMO was developed for TDD, which sends both upstream and downstream in the same frequencies. FDD uses separate frequencies, which makes it harder for the phone to provide the base station information it needs for best performance.
TDD performance is estimated at 3X (China Mobile,) 5-7X (India,) and
up to 10X (Softbank Japan.) Terrain has an enormous effect, so speeds are very different within and across networks.
T-Mobile is seeing somewhat lower rates, as expected.
- Published: 18 January 2018 18 January 2018
Large gains in wireless performance are possible with the right software.
Interference between cells and multiple signals seriously limits the performance of wireless networks. The problem becomes worse with today's very dense networks. Massive MIMO addresses that challenge with beamforming and intelligent design. Many of the theoretical problems remain open. The available solutions require enormous computing power.
Perfect solutions would require orders of magnitude more computing power than available today, but significant results are practical today.
Joe Farkas of Collision Communications believes they have particularly effective software that yields results approaching the ideal.
- Published: 27 December 2017 27 December 2017
Limited customers, speed only occasionally reached. Qatar Airlines is the first to deploy for Ooredoo's > 1 gigabit service, now being offered to selected customers in selected locations. C114, one of China's best tech pubs, is my source for the 1.2 gig speeds, confirmed by four other news publications. That the world leadership has left the U.S. and Europe is a major story, even if the details may be slight puffery.
Over a year ago, I discovered that True in Thailand was one of the first in the world to deploy 4x4 MIMO across the country, matched in 2017 in many other networks. That's just starting to be matched in the U.S. and Europe. Five companies - Ericsson, Huawei, Nokia, Samsung, and ZTE - are the source of almost all the 4G & 5G networks today. They sell the same gear in Qatar, Myanmar, Berlin, & Chicago. Except for Verizon and 5G mmWave - coming in 2018 - the Western telcos are no longer ahead.
- Published: 07 December 2017 07 December 2017
T-Mobile Netherlands and True Thailand choose 8 antennas for FDD spectrum, joining Kuwait in choosing Huawei gear. 8 antennas will rarely deliver twice the throughput of four antennas but will often deliver a 50% increase in capacity. 32/64 antenna Massive MIMO has been chosen by BT, DT, & FT but that is in higher frequencies running TDD.
32 antennas for 700 MHz spectrum would be too large to be practical most places. 256 antennas at mmWave frequencies are the size of a large chip and can go almost anywhere. 64 antennas at mid-frequencies like 2500 MHz need 1.5 to 3 meters, practical on most towers. Antenna size goes up with lower frequencies, making 32 antennas at 700 MHz a challenge and often impractical at 1800 MHz.
- Published: 13 October 2017 13 October 2017
Competition is fierce and spectrum is short, Reliance Jio spent $20B, built one of the best networks in the world, and gained 100M customers in the first year. Mukesh Ambani's aggressive plans for the 4G $20 (refundable) feature phone will probably add 100M more in the next year or so. Hundreds of millions of Indians are still on 2G. Ambani is ready to spend $B+ in subsidies to bring them to Jio 4G.
Giant Tata is closing their #4 mobile network, putting 10,000 out of work, writing off billions, and selling off cheaply to Bharti.. #5 Reliance Communications, Ambani's brother's company, is likely to follow. They couldn't compete in the price war. Vodafone and Idea, #2 & #3, are merging to stay alive
#1 Bharti's strategy in response includes a huge build of Massive MIMO, just announced. Danish Khan now reports the other two likely survivors, Jio and Vodafone/Idea, will also do Massive.
- Published: 06 October 2017 06 October 2017
381M customer Bharti Airtel, India's #1, has now turned on Huawei many antenna systems in Bangalore & Kolkata. Early results are doubling and tripling capacity. Bharti's pr, below, claims a 5-7 times improvement. That level of capacity and more will be possible as the software and algorithms improve, but the first generation is getting about half that.
China Mobile and Softbank pioneered M MIMO only a year ago. Now, the announcements are coming every week. Vodafone in England, Deutsche Te!ekom in the Netherlands and Hutchinson in Austria are officially moving from trials to commercial service. Sprint in the U.S. has a large network installed just waiting for Ericsson's final product release.
Bharti needs to keep up with Jio, the fastest growing network in the world.
- Published: 15 September 2017 15 September 2017
Tom Marzetta and other researchers have been very skeptical about the performance of Massive MIMO using FDD (Frequency Division Duplex) rather than TDD (Time Division.) Massive MIMO requires regular and robust reporting from the cell phone, which they feared would be impractical with FDD. Huawei, ZTE, and now Ericsson have done field trials they believe prove otherwise.
In trial with T-Mobile. Nishant Batra is confident many antenna Massive MIMO will add to performance in FDD frequencies as well as the TDD frequencies beginning to widely deploy. While the performance gain may not be exponential, directing the beam significantly increases capacity even in FDD systems.
- Published: 08 August 2017 08 August 2017
Achievable: Drastic drop in bad cell phone connections. Massive MIMO - 64 or more antennas - can dramatically improve edge performance by "beam forming," directing the signal where the users are. Done well, it can dramatically improve the performance where it's weaker. Hidebumi Kitahara of Softbank told me that is working very well and will get better as software improves. See "I am crazy about Massive MIMO," Kitihara of Softbank ordering 1,000's of Massive MIMO bases
Robert Clark of Light Reading reports Kitahara intends to use the capacity to improve performance for all users. "We don't care about peak throughput. We want to minimize the low throughput, which is between 1 Mbit/s and 5 Mbit/s." Clark adds, "At those speeds, the network will struggle to deliver a good video experience. Prior to deployment, around 20% of all users were experiencing throughput below 2 Mbit/s." Kitahara reveals, "only a few percent," now receive low speeds.
- Published: 05 August 2017 05 August 2017
MM depends on receiving back from the phone information on the channel. That uplink information has practical limitations on many cases, including from interference. In this paper, Bjornson, Hoydis, and Sanguinetti take on the assumption that there is a theoretical limit of spectral efficiency. Beginning with Marzetta, potential problems have been recognized.
"The pilot resources are limited by the channel coherence time, the same pilots must be reused in multiple cells. This leads to pilot contamination. ... it appears that pilot contamination is a fundamental issue that manifests a finite SE limit, except in some impractical special cases."
In 30 page dense with mathematics, the authors claim, "We will show in this paper that this is basically a misunderstanding,
- Published: 19 April 2017 19 April 2017
TDD Massive MIMO is already going wide at SoftBank Japan, yielding a 4x-10x capacity improvement on a single channel. Eric Zhao believes Massive MIMO is often the right choice where you need high capacity. Zhao finds early 32 antenna system averaging 450% more capacity in a single band. Many leading engineers agree MM is the way to go.
Worldwide, chief technologists are enthusiastic about Massive MIMO. At Huawei's MBB Forum, Hidebumi Kitahara of SoftBank confirmed the reported results, especially in crowded cells. Later in the day, Huang Yuhong of China Mobile also reported success. Her performance improvement estimates were "only" 3x, but it's early days for the technology. At SoftBank owned Sprint, Günther Ottendorfer reports a 10x improvement. Sanyogita Shamsunder of Verizon a year ago told me, "We must have massive MIMO." Nasser Al Nasser of Saudi Telecom in the release below reports a 6x improvement.