Today most people on Earth are connected through wired or wireless networks, or both. The next leap in connectivity will give people the ability to control objects and machines. The Internet of Everything (IoE) will tag objects with tiny wireless devices for communication, computation and sensing. Some projections show demand for such IoE smart sensors will grow from billions to trillions within a decade. The essential enabling technology is an ultra-low power smart radio to provide a unique IP address and location. In this talk, Amin Arbabian discusses how he developed an ant-sized wireless-powered radio chip that costs pennies to fabricate– making it cheap enough to become the missing link to enable the Internet of Everything.

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IoE as Connected Intelligence:
Radios for this new Era
Amin Arbabian
EE Department
Stanford University
December 4th 2014

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Internet of Everything
Network Source: General Electric
Source: Qualcomm
Source: GreenPeak Technologies Source: BrivoLabs
Source: Rockwell Automation
?

3. Image: Reuters
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Other Examples?
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Cellular Phones, 1970’s
Dr. Martin Cooper
Electricity, 1800’s
Today
Today

5. Source: Business Insider
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6. How To Design Wireless Connectivity For
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The Trillion “Things” Era?

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Inside a “Small” Radio
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Dust Networks
Nordic nRF24L01
Timing
Reference
Cost, Footprint, and Scalability
Power
Source:
Battery
Antenna
Chip/
Package/
Other

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Connecting a Trillion Things:
Most of IoE Connectivity will be
EXTREMELY ASYMMETRIC

9. Eliminating the Battery: Wireless Power
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Nikola Tesla 1899

10. Delivering Wireless Power to mm-Sized
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Sensors at a Distance
Distance-to-Size ratio

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Powering the Ant-Sized Radio
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Wavelength Mismatch:
Sensor Node Not to scale!
• TX: Inefficient Power Delivery and Focusing
• RX: Poor Power Pick-Up Efficiency

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Wireless Power Delivery
Optimal Freq. for wireless power delivery:
§ Assuming a fixed antenna gain for TX and RX

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Wireless Power Delivery
Optimal Freq. for wireless power delivery:
§ Assuming a fixed aperture for TX and RX
mm-Wave

14. -20
-25
-30
-35
Qc=5 Qc=10 Qc=20
Received -40
-45
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More Detailed Calculations
0
Power (dBm)
-20
-30
Received Power (dBm)
-40
-50
-60
-70
0 2 4 6 8 10 12 14 16 18 20
Frequency (GHz)
-10
Calculations for a mm-sized sensor
-10

15. mm-Wave Downlink
(power and data)
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Proposed Solution
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Uplink
mm-Wave
IoT Radios
Incoming Messages also used to Power Up
the Radios

16. Entire Radio on a Single Ant-Sized Chip
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Image: Shutterstock

17. • True single-chip solution- Nothing else connected
• Wireless energy delivery, synchronization,
communication, and multi-access
• Achieves 12Mbps for UL, Standby power <1.5μW
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Entire Radio Weighs 1mg
M. Tabesh, M. Rangwala, A. M. Niknejad, A. Arbabian, “A Power-Harvesting
Pad-Less mm-Sized 24/60GHz Passive Radio with On-Chip Antennas,” VLSI
Circuits (VLSIC), 2014 Symposium on. IEEE, 2014.

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Ant-Sized Radio in Action
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Next Stop: Human Body
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Jan M. Rabaey
L. Alarcon, F. Burghardt, D. Chen, A. S. Gambini, A. Kumar, Y.M. Li, T.T. Liu, N. Pletcher, J. Richmond
BWRC, EECS Dept.
Univ. of California, Berkeley
Pushing the
boundaries
further
Source Rex Features

20. ~7 cm 4
3.5
3
2.5
2
1.5
1
0.5
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The Power in Sound
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λ
Implant
(<1 mm3)
Aperture mismatch!
λ
Implant (1 mm3)
l << λ vp = 1.5 mm/μs, λ = 1.5 mm @ 1 MHz
mm-sized
focal spot
Gélat et. al., Phys. Med.
Biol., 2012
p v
f
λ =
Smaller dimensions (human hair)
Human body- a serious obstacle

21. Acoustic transducer array
Implants
Tissue
Ultrasonic power and
data downlink
RF/US data uplink
Incoming Sound Waves Carry Both Messages AND
Power to Activate Implants
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Sound-Powered Implants
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1st Generation Proof-of-Concept
Collaboration with Prof. Khuri-Yakub,
SOE Stanford Univ.
2nd Generation, in progress

23. Acknowledgements
Collaborators and Students:
• Prof. Khuri-Yakub, Dr. Amin Nikoozadeh, Prof.
Niknejad, Dr. Maryam Tabesh, Dr. Nemat Dolatsha,
Jayant Charthad, Jerry Chang, Marcus Weber,
Mustafa Rangwala
Funding Agencies and Support:
• DARPA Young Faculty Award Program (Dr. Doug
Weber)
• Stanford CIS/ System-X Alliance
• Stanford SOE Terman Fellowship
Ann Guerra
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