A highly-integrated dual technology (28nm and 130nm SOI) widely tunable software-defined RF duplexing front-end for FDD, FD, and TDD applications is presented. Predistortion and harmonic upconversion are used to cancel second and third harmonics generated by PA nonlinearity by up to 30 dB. A novel form of non-reciprocal, distributed degeneration is used to suppress TX noise that desensitizes the RX for full duplex operation. The distributed degeneration network improves RX noise figure by 7dB over baseline TX operation for same channel TX-RX. The transceiver achieves a 23dBm output power while maintaining more than 30dB of TX-RX isolation over the 0.8-1.2GHz band.
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Intelligent Remote Powering System With PTE Auto-Balancing For a Wireless and Batteryless EEG Cap
This work presents a fully battery-less and wireless (untethered) EEG readout cap. The powering system is equipped with a highly efficient and compact power transmitter mosaicked by an array of 8×11 Tx resonators in a certain pattern operating at the lowest ISM band of 6.78 MHz. The front-end’s power receiver block Rx includes multi-resonators mounted all-around an EEG cap that can be worn by a subject. Furthermore, considering the subject's head which could assume different positions, a well-designed positioning system and an intelligent feeding setup are developed to balance the efficiency drop due to misalignment and to involve the most associated resonators with the powering scenario with the potential of switching off the extraneous resonators that are not engaged with Transmit and Receive (Tx-Rx) power.
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- PAR ID:
- 10357209
- Date Published:
- Journal Name:
- 2022 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting
- Page Range / eLocation ID:
- 1724 to 1725
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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