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One of the design challenges of the implantable medical devices (IMD) is the power requirement that needs to be minimum to avoid frequent battery-replacement and surgeries. This paper presents a duty-cycled IR-UWB transmitter designed using standard 180 nm CMOS process that achieves an energy efficiency (energy-per-pulse) of 11.5 pJ/pulse at 100 Mbps data rate. Working in the frequency range of 4 - 6 GHz, the transmitter achieves a peak power spectral density (PSD) of -42.1 dBm/MHz with 950 MHz bandwidth which makes it highly suitable for high data rate biotelemetry applications. The bandwidth of the proposed transmitter system can also be varied from 500 MHz-950 MHz using control voltage of the impulse generator (IG). The wide frequency range and bandwidth range of the proposed transmitter also makes it highly suitable for distributed brain implant applications covering both lower and upper UWB frequency bands.
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A Digital Non-Foster VHF Radio Approach for Enabling Low-Power Internet of Things
A digital non-Foster radio approach is proposed to mitigate Wheeler-Chu limits of electrically-small antennas, with significant potential to significantly reduce energy consumption in the VHF (very high frequency) band, where radio propagation losses below 200 MHz are 100 times less than losses above 2 GHz. Operation at lower frequency could greatly extend lifetimes of small low-power Internet-of-Things devices such as battery-powered sensors operating primarily as transmitters. Unfortunately, physical size constraints and the Wheeler-Chu limit have greatly hindered utilization of VHF bands for mobile devices, where even a 200 MHz half-wave dipole is an unwieldy 0.75 m. However, recent advances in non-Foster impedance matching methods have overcome these limits. In addition, recent digital non-Foster methods are shown to closely resemble digital radio architectures, suggesting that these newer digital non-Foster methods can be readily adopted in new digital radio designs. Therefore, a novel digital non-Foster radio architecture is proposed, where digital non-Foster methods enable small devices in energy-efficient VHF bands while overcoming Wheeler-Chu antenna-size limits.
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- Award ID(s):
- 1731675
- PAR ID:
- 10318220
- Date Published:
- Journal Name:
- 2020 IEEE International Symposium on Circuits and Systems (ISCAS)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ISCAS45731.2020.9180893
