1. Networked Embedded Systems
EE107 Fall 2017
Lecture 1
Introduction
Networked Embedded Systems
Sachin Katti

2. EE107: Networked Embedded Systems
Goal: Provide a hands on introduction to the design of networked embedded systems Class will focus broadly on how to design a fully functional embedded system as well as use it for the function its designed

3. Logistics Instructors: Sachin Katti, Pengyu Zhang
TAs: Colleen Josephson, TBD
Lectures: Mon 4:30-5:20
Code review session: Wed 4:30-5:20
Lab sessions: Fri: 4:30-5:20
Office hours:
TBD
Web:

4. Lectures & Assignments
Lecture slides will be posted on the web
Four assignments
Due every two weeks
Assignments will be based on programming
Important to do them to keep pace in class
Everyone needs to work on his/her own assignment

5. Project & Exams
Final project: build an embedded vision and audio sensing system that transmits vision and audio data to the cloud which hosts AI/ML applications.
Done in groups of 2 or 3
Project presentation Dec 4 and Dec 6
One exam in class
Exam: Nov 15 in class

6. Grading Logistics Overall Class Grade Exam: 30% Four Assignments: 40%
End quarter project: 30%

7. What is a networked embedded system?
Computing systems are everywhere
Most of us think of “desktop” computers
PC’s
Laptops
Mainframes
Servers
But there’s another type of computing system
Far more common...

8. Networked Embedded Systems
Networked embedded computing systems
Computing systems embedded within things/gadgets connected to the network
Hard to call out any one thing/gadget, nearly everything now has a chip and a radio in it
Billions of units produced yearly, versus millions of desktop/laptop units

9. Typical Internal Structure

10. Examples

11. ICam: vision and speech interfaces for smart home
Motivation of building ICam
38 minutes for continuous face detection
Connected to a wall
Can we design a system that lasts for months on two AA batteries?

12. ICam: vision and speech interfaces for smart home
Let us work on math…
5000mAh/(50mA+300mA+500mA+800mA)=3hr
AA alkaline battery x 2 = 5000mAh
Power Consumption
Camera
50mA
WiFi
300mA
Codec
500mA
GPU processing
800mA

13. ICam: vision and speech interfaces for smart home
Let us work on math…
5000mAh/(50mA+300mA+500mA+800mA)=3hr
AA alkaline battery x 2 = 5000mAh
Power Consumption
Camera
50mA
WiFi
300mA
Codec
500mA
GPU processing
800mA
What is the power budget of a system that lasts for months on two AA batteries?
5000mAh/(60days x 24 hours)=3.47mA

14. ICam: vision and speech interfaces for smart home
Let us work on math…
AA alkaline battery x 2 = 5000mAh
Power Consumption
Camera
50mA
WiFi
300mA
Codec
500mA
GPU processing
800mA
Sub mA image sensor?
Low power radio?
Compute and process somewhere else?
HM01B0 image sensor (600uA)
Backscatter radio
Cloud processing

15. Why is radio power consumption high?

16. What is backscatter?
Signal reflection consumes much less power compared to active radio transmission

17. How does backscatter work?

18. How does backscatter work?

19. How does backscatter work?

20. ICam: vision and speech interfaces for smart home
UART
Envelope detector
DAC
MCU
Microphone
FPGA
Backscatter
Image sensor

21. ICam: vision and speech interfaces for smart home
Hardware
MCU that collects vision data from an image sensor and speech data from a microphone
A low-power backscatter radio board that wirelessly transmits data while consuming 2mA
Software in the cloud
AI and machine learning applications using the vision and speech data collected by the hardware

22. What will you take away from this project?
General knowledge of how an embedded system works
GPIO, Clocks, Interrupts, DMA, ADC, SPI, I2C, UART
Low-level firmware development in C
Device drivers
Digital signal processing
Hardware testing (and building)
Reading circuit layout and schematics
Analog circuit measurement (Oscilloscope, Multimeter)
Digital logic observation (Digital Logic Analyzer)
Surface mount soldering (I strongly suggest it)

23. Potential Projects Your ideas are GREAT! Who are you?
Propose and implement a cool application
Propose and implement something to make the system faster, more reliable or more power-efficient
Who are you?
Real time reliable face detection and recognition on the laptop life casting
What did you say?
Real time reliable speech recognition on the laptop
Secure and smart camera
Security camera - motion detection
Amazon Go using our camera running on top of battery with an energy budget

24. Potential Projects Run faster Low-power SD card data storage
Design 11Mbps backscatter radio on top of b WiFi packets
Low-power SD card data storage
Design and implement SDIO on an FPGA to allow energy efficient data storage
Toward battery-free
Design a more energy efficient architecture to stream data from the camera to a laptop. Beat Stanford SNSG architecture
Compression is quite power-intensive. Explore an all-analog or analog-assisted compression technique to try and save power
More is better
Implement a system that can run 2+ cameras simultaneously
Bonus: use these cameras to do 3D reconstruction