Full Duplex Radios in 5G

Sachin Katti

Chief Scientist, Kumu Networks

Professor, Stanford University

6/27/2014 1 Proprietary and Confidential

Kumu Networks Challenging the basic assumptions of wireless networking

2

Executive Team and Investors

• Stanford EE & CS faculty and PhD founders

• Augmented with industry veterans & top investors

Invented In-Band Full Duplex Radios

• Breaks a century old assumption in wireless

• Rich Patent Portfolio & several research awards

Proprietary and Confidential

Until today radios could not transmit and receive

at the same time on the same channel

Why Are Radios Today Half Duplex?

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TX

RX

RX

TX

Radio 1 Radio 2

Self-Interference is billions of times stronger

than the received signal

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Kumu Radios can transmit and receive on the

same channel!

Kumu In-Band Full Duplex Radios

4

Kumu’s patented self-interference cancellation technology

completely isolates the RX from the TX interference

TX

RX

RX

TX

Radio 1 Radio 2

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Self-Interference Cancellation enables full-duplex,

doubles spectral efficiency

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Frequency 1 Frequency 2

Kumu Full Duplex Radios

Transmitted Signal

Received Signal

Transmitted Signal

Received Signal

FDD: paired frequencies needed

Full-duplex: Single frequency, same performance

Full Duplex Doubles Spectral Efficiency

in face of slowing gains due to

coding technology limits

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0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

HSPA Rel-6 1x2 HSPA Rel-7 1x2 HSPA Rel-7 2x2 LTE 1x2 LTE 2x2

Bit

s/Se

c/H

ert

z

Spectral Efficency Gains

1.42 1.36

1.29

1.08

0.72

Source: NGMN

It’s a big deal

Full Duplex Remote Radio Head

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Full Duplex Performance Independently Tested &

Verified by leading tier-1 operators

isolator

Σ

6/27/2014 Proprietary and Confidential 8

PA LNA

Cancellation Front-End

ANT

Modem

Transceiver

Simple front-end addition to any radio

Existing Radio

Kumu’s Self Interference Cancellation is

fundamental, applies broadly beyond full duplex

Ultimate Tunable Radio Head

9

Transmitted Self-Interference

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Channel 1 Channel 2

In-Band Full

Duplex

Double capacity

Received Signal

Adaptive

Frequency

Division Duplex

(FDD)

Flexibly decide which

channels to transmit

& receive on

Transmitted Self-Interference

Received Signal

Channel 1 Channel 2

Frequency agnostic universal cancellation:

In-band, side-band, any-band

Ultimate Tunable Radio Head

10 Proprietary and Confidential

Opportunistically use

underutilized spectrum

Universal roaming phones

that operate on all bands

LTE-u

Modem

PA

LNA

TX

Chain

RX

Chain

Universal Kumu Duplexer

Core Next-Generation Technology applicable in

multiple markets

LTE Access High performance Relay

Node. Doubles spectral

efficiency for TD-LTE.

WiFi Access Dense coverage by avoiding

interference between

adjacent bands

Mobile Devices World phones supporting

any FDD channel pairs with

adaptive duplexers

Microwave

Backhaul Doubles spectral efficiency,

and mitigate interference in

unlicensed bands

Full Duplex Everywhere

11 Proprietary and Confidential

Self-Backhauled Small Cell removes all the

barriers for successful small cell deployment

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Immediate, standards compliant use case

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Full Duplex Self-Backhauled

Small Cell

FDD Macro No Changes/Extra Equipment

Free Backhaul

In-Band NLOS LTE

Same channel for access and

backhaul simultaneously

Capacity

On-Par with a Small

Cell with Fiber

Simple to Deploy

Only Requires

Power

FDD UE No Changes

DL

UL

Self - Interference

To conclude

6/27/2014 13 Proprietary and Confidential 13

• Full duplex technology is real, proven and tested

• Full Duplex 5G Air Interface is inevitable:

– Double spectrum efficiency, enable new

spectrum use and flexibility

• Kumu Networks: the full duplex company

Full Duplex Future

Full-Duplex Revolution

6/27/2014 14 Proprietary and Confidential