| 2 |
A Wake-Up Circuit for Event-Driven Duty-Cycling of Wearable IoT Sensor Nodes
|
|
|
|
Abstract:
The design of IoT sensing nodes mandate unprecedented tight constraints on power consumption, physical volume, and production costs which limits the on board processing and data-transfer capabilities. Efficient real-time processing can be achieved by exploiting system-level duty-cycled architectures and novel mixed-signal processing circuits that detect and transmit only events of interest reducing power-hungry raw data transfer. In this dissertation we report an always-on wake-up circuit and a high-performance biomedical SoC designs and implementations that can be employed in IoT sensing nodes. The wake-up circuit is based on a level-crossing analog-to-digital converter (LC-ADC) employed as feature-extraction block with automatic activity-sampling rate scaling behaviour. A novel asynchronous digital logic classifier for sequential pattern recognition is presented and it is supervised-learning trained to maximize events detection accuracy. It is driven by the LC-ADC activity and trained to minimize classification errors due to falsely detected events. A prototype has been first validated by interfacing it with a commercial accelerometer to classify hand gestures in real-time, reaching 81% of accuracy with only 2.2 μW at 1 V supply. To highlight the flexibility of the design, a second application, detecting pathologic ECG beats is also discussed. Furthermore, an application based on the novel biomedical System-On-Chip (SoC) for signal acquisition and processing combining a homogeneous multi-core cluster with a versatile bio-potential front-end is described. The presented implementation acquires raw EMG signals from 3 passive gel-electrodes and classifies 3 hand gestures using a Support Vector Machine (SVM) pattern recognition algorithm. Performance matches state-of-the-art high-end systems both in terms of recognition accuracy (> 85%) and of real-time execution (gesture recognition time 300 ms), requiring only 10 mW.
|
|
Keyword:
classifier; CMOS; computer science; Data processing; Electric engineering; event driven; info:eu-repo/classification/ddc/4; info:eu-repo/classification/ddc/621.3; IoT; sensing node; Ultra Low Power; Wake-up circuit; Wearable
|
|
URL: https://doi.org/10.3929/ethz-b-000281405
https://hdl.handle.net/20.500.11850/281405
|
|
BASE
|
|
Hide details
|
|
|
| 8 |
Der semantische Kommentar in gegenwartsbezogenen Sprachkontaktwörterbüchern
|
|
|
|
BASE
|
|
Show details
|
|
|
| 15 |
Quanti sono gli italianismi nel tedesco contemporaneo?
|
|
|
|
In: ItalianoLinguadue; Vol. 1 No. 1 (2009); 160 ; Italiano LinguaDue; V. 1 N. 1 (2009); 160 ; 2037-3597 (2009)
|
|
BASE
|
|
Show details
|
|
|
|
|
