Same frequency, same time, ?double wireless speeds. Today, self-interference makes it impractical to send and receive at the same time on the same frequencies. Testing at Deutsche Telekom and SK Telecom suggests Moore's Law is bringing enough processing power to change that. (pr below.) They are working with Kumu Networks, a spinoff from the lab of Stanford's Philip Levis. Their extraordinary advisory board gives them extra credibility.

Research on Full Duplex is hot.  An article by Sabharwal et. al. lists 141 papers (below.) At Columbia,  Harish Krishnaswamy has developed chips. At a Cambridge Wireless meeting, David Lister of Vodafone concluded, "We can consider the problem of self-interference cancellation as solved. Now is the time to consider system requirements and assess the use cases. There are still major challenges to overcome."

Joel Brand of Kumu is confident. "By the second half of 2016 we could ship full-duplex solutions for infrastructure applications where the requirements are a bit more relaxed than in a mobile phone." WISP backhaul would be a natural niche for this kind of product. 

Some are skeptical about the potential to double performance in the real world.

Xiufeng Xie and Xinyu Zhang of the University of Wisconsin believe "While it is tempting to believe that full-duplex can double wireless capacity, this paper disproves the perception through asymptotic analysis and network optimization. Indeed, for a single link, full-duplex may have a capacity gain of 2 over half-duplex, but in large-scale wireless networks, spatial reuse and asynchronous contention effects significantly undermine the actual benefits of full-duplex." 

Brand thinks performance degradation will rarely be important in practice. "There are some improvements that need to be made at the MAC layer in order to prevent phone-to-phone interference on the broadcast channels in an environment where everything is on a single frequency. There are plenty of proposals in academia (one actually from Phil Levis) and in the industry (check some of the work that has been done around High Efficiency WiFi) to address that. It will result in doubling the spectral efficiency of what existing systems can provide, or at least come very very very close to that." 

The best engineers I know expect wireless capacity to increase fifty times or more. Full Duplex may be one of the tools.

 

 Thanks to Telecoms.com for pointing me to this story. Here are some of the primary sources.

From Kumu Networks, an impressive list of investors and advisors. 

• Philip Levis, Professor of EE and CS at Stanford University, Co-Founder
• Sachin Katti, Professor of EE and CS at Stanford University, Co-Founder 
• Nick McKeown, Professor of EE and CS at Stanford University
• Bernd Girod, Professor of EE and CS at Stanford University
• Andy Rachleff, Alumni Partner at Benchmark Capital, Faculty Member at Stanford GSB
• Jon Peterson, Fellow at Neustar, Member of the Internet Architecture Board
• Sanjit Biswas, CEO, Meraki Inc.  
• Guru Parulkar, Consulting Professor, Stanford University
• Arogyaswami Paulraj, Professor Emeritus of EE, Stanford University
• New Enterprise Associates [Forest Baskett, Ron Bernal]
• Khosla Ventures
• Third Point LLC [Rob Schwartz]

SK Telecom – Kumu Networks Demonstrate In Band Full Duplex, a Key Pre-5G Technology at World IT Show 20152015.05.27

– SK Telecom (NYSE:SKM) announced today that, together with Kumu Networks, it will demonstrate a robot traffic officer using In Band Full Duplex (IBFD) technology at the World IT Show 2015 (WIS), to be held in Seoul, Korea from May 27 to 30. 

IBFD is being highlighted as one of the key pre-5G technologies as it enables simultaneous in-band uplink and downlink communication by cancelling signal interference in real time, thus significantly enhancing the spectral efficiency.

As the current networks cannot transmit and receive signals at the same time on the same channel, mobile operators have to choose either FDD or TDD to enable communication between base stations and handsets.

At this year’s WIS, SK Telecom and Kumu Networks will showcase a new Robocop tasked with traffic management in the pre-5G network environment applied with the IBFD technology. Built with a camera, microphone and multiple sensors, the Robocop not only mirrors human movement without latency, but also transmits/receives multimedia data – both video and audio – to/from the control center in real time

As the demonstration shows in detail how 5G networks can wirelessly transmit and receive massive amounts of data in a real-time manner, it is expected that 5G, once realized, will enable flawless provision of innovative IoT services.

SK Telecom and Kumu Networks have signed a Memorandum of Understanding for technology cooperation on March 2, 2015 at the Mobile World Congress 2015 held in Barcelona, Spain. Kumu Networks, a California-based developer of wireless transmission and signal processing technology, is the leader in the field of IBFD technology.

“SK Telecom is delighted to demonstrate IBFD, a key pre-5G technology, together with Kumu Networks,”said Alex Jinsung Choi, CTO of SK Telecom.“We will continue to drive innovations towards the 5G era by seeking and developing enhanced network technologies with our partners.”

“SK Telecom’s wirelessly controlled traffic robot is the perfect metaphor for Full Duplex’s role in alleviating wireless traffic jams,” said Kumu Networks CEO David Cutrer. “We are very excited to work with SK Telecom as they trial and deploy cutting edge In Band Full Duplex applications to boost today’s wireless network capacity and pave the way to 5G.”

About SK Telecom

SK Telecom (NYSE: SKM, KSE: 017670), established in 1984, is Korea’s largest telecommunications company with more than 28 million mobile subscribers, accounting for around 50% of the market. The company reached KRW 17.164 trillion in revenue in 2014. As the world’s first company to commercialize CDMA, CDMA 2000 1x, CDMA EV-DO and HSDPA networks, SK Telecom launched the nation’s first LTE service in July 2011. SK Telecom also became the world’s first mobile carrier to commercialize 150Mbps LTE-Advanced in June 2013 and 225Mbps LTE-Advanced in June 2014 through Carrier Aggregation(CA). In line with its efforts to swiftly move towards the next-generation mobile network system, or 5G, it successfully commercialized 300Mbps tri-band LTE-A CA. As of the end of March 2015, the company has over 17.4 million LTE and LTE-Advanced subscribers. Based on its strength in network operations business, SK Telecom is seeking new growth engines through three innovative platforms namely Lifestyle Enhancement Platform, Advanced Media Platform and IoT Service Platform. For more information, please visit www.sktelecom.com or email to This email address is being protected from spambots. You need JavaScript enabled to view it..

 

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By the second half of 2016 we could ship full-duplex solutions for infrastructure applications where the requirements are a bit more relaxed than in a mobile phone.