(A) 5-Gbps ook gain-boosting demodulator for 60 GHz wireless terminals

Abstract

This thesis presents 5Gbps gain-boosting demodulator in $0.13\microm$ CMOS for 60 GHz application. Customer demand for a higher data rate is increasing each year. Next generation wireless personal area networks (WPAN) 60 GHz band requires data rate over 1 Gbps. 60GHz band has a worldwide common unlicensed band of 3GHz, and transmits high data over 1 Gbps without complicate modulation schemes. One of the strongest applications is handheld device because user has handheld devices and carries some of them. For this application operated in battery, low power consumption is a key issue. On-off keying (OOK) modulation scheme is the best suitable way since this scheme does not need local oscillator. Demodulator converts 60 GHz modulated signal into information of a digital signal with low power consumption. However, main demerit of the OOK demodulator is high conversion loss that increases power consumption and limits high data transmission. Design issue of demodulator is increase in conversion gain. In this thesis, we introduce gain-boosting technique to improve higher conversion gain. Demodulator consists of detector, gain-boosting stage, voltage level shift, and 3-stage resistive feedback baseband amplifier. A voltage responsivity of gain-boosting demodulator is 1.5 times larger than conventional demodulator, and baseband amplifier has 3-dB bandwidth of 4 GHz. Demodulator occupies $365 x 852 \microm^2$, consumes DC power of 14.7 mW. Input return loss is below -10 dB at the 60 GHz unlicensed band from 57 GHz to 66 GHz, and detector has a voltage responsivity of 2434 mV/mW. Conversion gain of demodulator is 13.6 dBm at the -16 dBm input power. These conversion gain and voltage responsivity demonstrate high performance and possibility in low power system. Furthermore, measure eye diagram shows 5 Gbps data rate, and energy per bit indicating energy efficient is the highest value of 2.94pJ/bit among ever published papers. Finally, these measured values show tha...