Low-power radio design for IoT
Topic outline
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Welcome to the course on Low-power Radio Design for the IoT
The wireless telegraph is not difficult to understand. The ordinary telegraph is like a very long cat. You pull the tail in New York, and it meows in Los Angeles. The wireless is the same, only without the cat.
Albert Einstein, 1938
Summary
One of the basic function of an IoT node is to collect data, process it and send it to the cloud through a wireless channel. Despite the scaling of CMOS technology and the progress made in low-power circuits, today, the power consumption of IoT nodes is largely dominated by the wireless communication and particularly by the radio. It is therefore key to understand the various trade-offs faced when designing a radio embedded into an IoT node.
This course starts with a short introduction to the field of IoT with a particular emphasis on the wireless communication aspects, including a short description of the standards, including short-range connectivity (e.g. Bluetooth, BTLE,…) and Low Power Wide Area Network (LPAW) (e.g. Lora,…). It then gives a high-level description of a typical IoT node and brief description of the radio. The principles of wireless communication are then recalled with a particular focus on digital wireless communication and standards used for the IoT. The basics principles of RF design are then presented, introducing the key concepts and definitions. The different radio architectures that are appropriate to IoT nodes with respect to their complexity and power consumption are then presented. The main building blocks are then described and analyzed in details with a particular focus on their power consumption.
Contents:
- Introduction to IoT
- Wireless communication principles and standards
- Basic concepts in RF design
- Modeling of active and passive devices at RF
- Noise at RF
- Basic transceiver architectures
- Low-noise amplifiers (LNAs)
- Mixers
- Oscillators
Power amplifiers (PAs)
Program
Course schedule and timing (Spring Semester 2022)
This course will be given in room DIA 003 every Thursday from 10:15 to 12:00 with a break between 11:00 and 11:15. It is followed by the exercise session from 12:15 to 13:00.
Video recordings of last years course (2021)
Below are the links to the video recordings of last years course:
Resources
Books
- B. Razavi, RF Microelectronics, 2nd ed. Pearson, 2012.
- T. H. Lee, The Design of CMOS Radio-Frequency Integrated Circuits, 2nd ed. Cambridge University Press, 2004.
- Enabling the Internet of Things – From Integrated Circuits to Integrated Systems, Massimo Alioto, Editor, Springer 2017.
Exam
The exam is a written exam that will take place on June 30 from 15:15 to 18:15 in room ELA 2. The exam is open book and you can use your notes on your tablet or laptop but the device should be in flight mode (not connected to the internet). The exam is an individual effort and you should not communicate.A mock-up exam is available below.
Q&A Session
A Q&A session will take place on June 27 at 2pm in room DIA 003 (the room we had the lectures). The session will also be broadcasted via zoom. You can use the following link to join the meeting:
https://epfl.zoom.us/j/66943343816
Prepare your questions ahead of time so we can have an efficient meeting.
Mock-up exam
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Outline:
- Course description
Introduction to the Internet of Things (IoT)
Slides:
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Outline:
- Passive RF circuits
Impedance matching
Slides:
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Outline:
- General Considerations
- Analog Modulation
- Digital Modulation
- Power Efficiency of Modulation Schemes
Noncoherent Detection
Slides:
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Outline
- General considerations
- Nonlinearity and time variance
- Effects of nonlinearity
- Single tone input
- Harmonic distortion
- Gain compression
- Two-tone input
- Desensitization and blocking
- Cross modulation
- Intermodulation
- Third-order Intercept Point
- Cascade of nonlinear stages
Slides
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Outline
5.1 Modeling of Passive Devices
- Inductors
- Transformers
- Transmission lines
- Varactors
- Constant capacitors
5.2 Modeling of the MOS Transistor at RF
- Transistor Figures-of-Merit (FoM)
- Equivalent Circuit at RF
- Large-signal Model at RF
Summary of the EKV MOS Transistor Model
A summary of the EKV MOS transistor model is provided for the student who did not follow the "Advanced Analog and RF IC Design I" course.Slides
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Outline
- Noise in two-port networks
- The noisy two-port The noise factor
- The minimum noise factor and noise parameters
- The Friis formula
- Noise in the MOS transistor at RF
- The small-signal noise circuit at RF
The minimum noise factor of a single transistor
Slides:
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Outline
- General Considerations
- Heterodyne Receivers
- Homodyne Receivers
- Image-Reject Receivers
- Low-IF Receivers
- Discrete-time Receivers
Slides
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Outline
- LNA design
- Low-power LNA design
Slides
- LNA design
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Outline
- Passive mixers
- Active mixers
Slides
- Passive mixers
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Outline
10.1 Basic oscillators
- General considerations
- The 3-point oscillator
- The cross-coupled pair oscillator
10.2 Phase noise
- Fundamentals
- Linear analysis
- Nonlinear analysis
Slides
- General considerations
