Trading Sensitivity for Power in an IEEE 802.15.4 Conformant Adequate Demodulator
Paul Detterera, Cumhur Erdinb, Jos Huiskenc, Hailong Jiaod, Majid Nabie, Twan Bastenf and José Pineda de Gyvezg
Electonic Systems group, Eindhoven University of Technology, Netherlands
ap.detterer@tue.nl
bc.erdin@tue.nl
cj.a.huisken@tue.nl
dh.jiao@tue.nl
em.nabi@tue.nl
fa.a.basten@tue.nl
gj.pineda.de.gyvez@tue.nl
ABSTRACT
In this work, a design of an IEEE 802.15.4 conformant O-QPSK demodulator is proposed, which is capable of trading off receiver sensitivity for power savings. Such design can be used to meet rigid energy and power constraints for many applications in the Internet-of-Things (IoT) context. In a Body Area Network (BAN), for example, the circuits need to operate with extremely limited energy sources, while still meeting the network performance requirements. This challenge can be addressed by the paradigm of adequate computing, which trades off excessive quality of service for power or energy using approximation techniques. Three different, adjustable approximation techniques are integrated into the demodulation to trade off effective signal quantization bit-width, filtering performance, and sampling frequency for power. Such approximations impact incoming signal sensitivity of the demodulator. For detailed tradeoff analysis, the proposed design is implemented in a commercial 40-nm CMOS technology to estimate power and in Python to estimate sensitivity. Simulation results show up to 64% power savings by sacrificing 7 dB sensitivity.
Keywords: Internet-of-Things,Wireless Networks, O-QPSK Demodulator, FIR Filter
