A compact and low-power wireless receiver for implanted medical backscatter

Abstract

A compact and low-power wireless receiver supporting 2.4 GHz industrial, scientific and medical (ISM) band is implemented in a 130 nm Complementary Metal-Oxide-Semiconductor (CMOS) process. The GHz operating frequency renders the chip to be matched with a mm-sized antenna to reduce implants' size and improve patients' experience. To simplify the implanted chip, the downlink is through On-Off Keying (OOK) so non-coherent detection and simplified receiver chain can be deployed. Boosted Rectifier and open-loop amplifier-based receiver chain lowers the chip's power consumption to nW level. The measured sensitivity reaches −50 dBm at a Bit Error Rate (BER) of 1e-3.

An ultra-fast and high-precision VCO frequency calibration technique for fractional-N frequency synthesizers

“…This is quite suitable for those high performance communication systems such as the frequency-hopping system, because PLL always works and the frequency or the sub-band of VCO changes continually in frequency-hopping system. On the other hand, the proposed AFC circuit is not suitable for low power communication systems, such as biomedical electronic system [30,31]. Because PLL may be turned off frequently for low power design, it requires long time to set up the TOF while PLL power on every time, and the set up time of TOF will be added to calibration time in such situation.…”

Monitoring of driver’s biomedical signals using LoRa-based wireless communications

“…The used frequency band, bit rate, and dc voltage is 433MHz, 300 kbps, and 5 V dc, respectively. The other parameters can be refereed in [27]- [28]. In power unit, a voltage regulator is employed to transform 12 V dc from the vehicle to 5V dc.…”

A low-power high-output-efficiency bipolar Colpitts VCO using base inductive feedback and Q-factor enhancement for analog signal acquisition

“…The low-power demand is becoming more and more significant as the development of portable wireless communication system, such as the battery-powered nodes in the IoTs (Internet of Things) [1][2][3][4], short-range wireless biological signal acquisition devices [5][6][7][8], sensor networks [9,10]. In many wireless scenarios of external analog signal acquisition, the system's power consumption is limited extremely to the microwatt level.…”