Fierce 15 2016: Kumu Networks is spearheading a Full Duplex Revolution

Image: Flickr user Timoir III
Fierce15 2016

Editor's note: Welcome to the 2016 Fierce 15, an annual list that recognizes 15 of the most interesting startups in the wireless industry. We'll publish one profile a day for 15 days; Kumu Networks is the seventh company to be recognized this year.

Company: Kumu Networks
Where it's based: Sunnyvale, California
When it was founded: 2012
Website: kumunetworks.com

Why it's Fierce: Kumu Networks is spearheading a Full Duplex Revolution and wants to change the fundamentals of wireless networking. Founded by a team of Stanford University graduates and Ph.D. graduates, it moved from the lab to field trials in relatively short order, attracting the attention of Verizon, Singtel, SK Telecom, Deutsche Telekom, Telefonica, Swisscom, TIM and Cisco.

Its founders invented technology to improve how wireless spectrum is used, addressing those capacity constraints that so many operators are experiencing. Several operators are using Kumu’s equipment in field trials now and it’s on a mission to not only commercialize its technology, but shape future standards to promote Full Duplex.

The company employs 30 people and earlier this year completed a strategic round of $25 million from investors including Cisco, Verizon Ventures and Deutsche Telekom, among others. It is in field trials serving live consumer traffic.

The problem that Kumu aims to solve has to do with the fact that radios cannot transmit and receive at the same time on the same channel, requiring FDD or TDD duplexing. Kumu's self-interference cancellation technology isolates the receiver from the transmitter, allowing radios to transmit and receive simultaneously on the same frequency. Wireless Full Duplex allows a radio to transmit and receive overlapping signals using a single frequency channel at the same time. With Self-Interference Cancellation, the access and backhaul radios can operate simultaneously on the same frequency, allowing the small cell to backhaul itself while maintaining end-to-end throughput.

Joel Brand, Kumu's vice president of product management, describes it like this: When a normal radio transmits, it makes so much noise, it can't receive the signal from the other end --"it's like trying to listen to a whisper while screaming at the top of your lungs." What Kumu succeeds in doing is putting a device in front of the antenna and canceling the self-interference. "The concept is, let's connect something between your mouth and your ear such that when you scream, you don't hear yourself," he said. "That's what we've done. We're connecting a device between the transmitter of the radio and the receiver of the radio, and we silence the transmitted signal to the 'ear' of the radio.” Once you silence the "noise," you can hear everything else.

But it faces a long way before standards change. “Let’s face it, the world has been FDD and TDD for the last 150 years, and we’re not going to change that overnight,” he said. “That will require standard changes and that will require different ways of designing radios” because every radio today assumes that it’s FDD or TDD and everything is structured around that. “We need to change things,” he said, and that won’t happen immediately.

Wireless Full Duplex allows a radio to simultaneously transmit and receive overlapping signals using a single frequency channel. When Full Duplexing transmission is achieved, that changes fundamentally the way the world thinks about spectrum allocation, Brand said. At a bare minimum, Kumu says, it can double capacity.

What’s next: The ultimate goal is the change the standards to Full Duplex. In the meantime, the company is focusing on applications that don’t require changes to base stations and phones. Kumu’s Self-Backhauled Small Cell removes the key obstacle for large small cell deployments, using the same channel for access and backhaul at the same time. The company aims to start earning revenue in the next six to 12 months, if not sooner, and it is working on a more miniaturized version of its technology. It expects to continue field trials indefinitely and expects to work with five or six operators spread across the U.S., Europe and Asia by the end of the year.

Read more: FierceWireless's Fierce 15 2016