Browsing by Author "Gong, Cihun-Siyong Alex"

Now showing 1 - 3 of 3

A direct conversion transmitter with digital-assisted DC offset and I/Q phase calibration
(2017-12-01)
Chang, Chia-Hung
;
Chen, Wei-Hsien
;
Gong, Cihun-Siyong Alex
;
Hu, Wei-Wen
;
電機工程學系
A direct conversion transmitter with auto-calibration mechanism is presented in this paper. Both the carrier leakage and in-phase/quadrature (I/Q) phase imbalance are compensated by a proposed calibration algorithm to improve transmitter's single-sideband performance. The digital-assisted correction circuits are implemented in a calibration feedback path to reduce the mismatches and variations, which in turn achieves properties of high linearity, high sideband, and carrier suppression ratio. The measured single-sideband performance with calibration applied to the transmitter demonstrates an over 40 and 50-dBc rejection on sideband and carrier signals at the desired frequency band, respectively. For linearity performance, the measured output 1-dB compression point (OP1dB) is 9.1dBm, while the highest voltage gain is from 4.3 to 6.2dB. Additionally, the error vector magnitude (EVM) of -37.082dB (< 1.4%) can be achieved under an orthogonal frequency division multiple access (OFDMA) 64 QAM-3/4 modulated signal test. The transmitter consumes 112.7mA under supply voltage of 3.3V using the TSMC SiGe BiCMOS technology. Copyright (c) 2017 John Wiley & Sons, Ltd.
An Ultra Low-power Wakeup Receiver for Energy-efficient Wireless Senor Network
(2014-01-01)
Tsou, Yu Lin
;
Gong, Cihun-Siyong Alex
;
Jou, Christina F.
;
交大名義發表
;
National Chiao Tung University
An ISM band sub-100 mu W Wake-Up Receiver (WuRx) has been presented in this study. Issues regarding tradeoffs between system architectures for Ultra-Low Power (ULP) WuRx are analyzed and compared. Push-Pull Current Re-Use (PPCRU) topology with programmable bias-controlled technique has been proposed for maximum conversion gain requirement for minimum power consumption. The chip of WuRx is 0.79 mm(2) in size and has been implemented in a 0.18-mu m CMOS technology. Measurement shows this technique increases conversion gain by 4.8 dB without extra core current consumption which comes the result of 3.7 dB figure-of-merit (FOM) improvement. Minimum power consumption of WuRx is 88.8 mu W from 1.2-V supply. When operating at 100 kbps data rate, the sensitivity is -63 dBm (10(-3) BER) with 888-pJ/b energy consumption. Owing to gain improvement function in RF front end, the optimum FOM of 183.4 dB can be achieved. Therefore, the proposed gain-improved technique fulfills optimum system performance between power consumption and conversion gain requirement.
Integrated Biosensing Platform Based on a 1.74-mW-90-dBm Sensitivity Dual-Mode-Operation Receiver for IEEE 802.15.6 Human Body Communication Standard
(2015-06-01)
Tsou, Yu Lin
;
Gong, Cihun-Siyong Alex
;
Cheng, Nai Chen
;
Lee, Yu
;
Jou, Christina F.
Human body communication (HBC), a technique featuring low conduction loss and low interference by taking the advantages of the nature of body composition, has emerged as one of the most promising techniques toward next-generation wireless body area network (WBAN). The regulation of WBAN, IEEE 802.15.6, concerning the standard of physical layer has also been established in 2012. The intensity of electric field around body is affected by the transmission distance, quality of electrode-skin contact, and so on which results in wide variance in path loss. In addition, according to the measurement results, the equivalent capacitance of electrode-skin interface increases path loss significantly when noncontact transmission happens. To solve the problems, a low-power receiver with dual-mode operation is proposed in this paper. The receiver has been implemented in a standard 0.18-mu m CMOS process measurement shows the receiver is fully functional with power consumption < 1.75 mW under 1.2 V supply voltage and compatible with IEEE 802.15.6 HBC layer. The chip size is 1.05 mm(2). Maximum voltage conversion gain can be 85.5 dB. Experimental sensitivity is up to -90 dBm under an information data rate of 164 kb/s. It has been demonstrated that the receiver provides successful text file transmission through human body with the fabricated sensing electrodes.