title: A sub-nW 2.4 GHz Transmitter for Low Data-Rate Sensing Applications.
abstract: This paper presents the design of a narrowband transmitter and antenna system that achieves an average power consumption of 78 pW when operating at a duty-cycled data rate of 1 bps. Fabricated in a 0.18 µm CMOS process, the transmitter employs a direct-RF power oscillator topology where a loop antenna acts as a both a radiative and resonant element. The low-complexity single-stage architecture, in combination with aggressive power gating techniques and sizing optimizations, limited the standby power of the transmitter to only 39.7 pW at 0.8 V. Supporting both OOK and FSK modulations at 2.4 GHz, the transmitter consumed as low as 38 pJ/bit at an active-mode data rate of 5 Mbps. The loop antenna and integrated diodes were also used as part of a wireless power transfer receiver in order to kick-start the system power supply during energy harvesting operation.
authors.affiliation: Department of Electrical and Computer Engineering, University of California at San Diego, 9500 Gilman Dr., 0407, La Jolla, CA ( pmercier@ucsd.edu , phone: 858-534-6026).
authors.forename: Patrick P
authors.initials: PP
authors.lastname: Mercier
authors.affiliation: Texas Instruments, Dallas, TX.
authors.forename: Saurav
authors.initials: S
authors.lastname: Bandyopadhyay
authors.affiliation: Massachusetts Eye and Ear Infirmary, Boston, MA, and the Harvard/MIT Joint Division of Health Sciences and Technology, Cambridge, MA.
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Lysaght
authors.affiliation: Massachusetts Eye and Ear Infirmary, Boston, MA, and the Harvard/MIT Joint Division of Health Sciences and Technology, Cambridge, MA.
authors.forename: Konstantina M
authors.initials: KM
authors.lastname: Stankovic
authors.affiliation: Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology (MIT), Cambridge, MA.
authors.forename: Anantha P
authors.initials: AP
authors.lastname: Chandrakasan
keywords: Body-sensor networks; energy harvesting; low power electronics; power amplifiers; radio frequency integrated circuits; voltage-controlled oscillators; zero-power electronics