Design and Implementation of Voltage Controlled Oscillators for Wireless Data Transmission System in Digital Home

• Main Authors: Cheng-yu Chen, 陳政佑
• Other Authors: Jia-shiang Fu
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/68880048375902709533

碩士 === 國立中央大學 === 電機工程學系 === 102 === In RF transceivers, voltage controlled oscillator (VCO) is an indispensable circuit block. The function of a VCO is to provide a stable signal source for up-converting and down-converting the transmitted and received signals, respectively. Important metrics for VCO include frequency tuning range, phase noise, DC power consumption, and RF output power. The advance of electronic technology enables digital life. In digital-home scenario, the transmission of multimedia content with both video and audio is necessary. In recent years, the demand for high-definition (HD) video transmission has increased and the associated wireless standards are successively defined, including WirelessHD and WHDI, which use 60-GHz band and 5-GHz ISM band, respectively. For wireless transceivers, it is a common practice to use two RF signals whose phases are 90° in difference to modulate or demondulate the baseband I/Q signals. Therefore, we first develop a 60-GHz quadrature VCO (QVCO), which can provide the quadrature RF signals required in wireless front-ends. The circuit adopts traditional parallel-QVCO topology and is implemented using TSMC 90-nm CMOS techonology. The measured oscillation frequency can be tuned from 60.61 GHz to 63.01 GHz, which corresponds a frequency tuning range of 3.88%, as the control voltage is swept from 0 V to 1.2 V. At 10-MHz offset, the minimum phase noise and FoM are −89.61 dBc/Hz and −155.1 dBc/Hz, respectively. With the frequency tuning range, the output power is −25.8±2 dBm and DC power consumption of the VCO core is less than 11.1 mW. At control voltage is 0.4 V, the minimum phase and amplitude error are 3.25° and 0.39 dB, respectively. Next, in an RF system with numerous circuit blocks, the testing could be costly and time-consuming. To overcome this difficulty, the concept of built-in self test (BIST) can be applied. BIST would not only reduce the cost of testing but provide the capability of real-time monitoring. We design a VCO that has built-in envelope detectors integrated with it and demonstrate its potential for RF BIST by relating the output voltage of the detectors with the output power of the VCO. The VCO is designed and implemented in TSMC 0.18-μm CMOS. On 1.8-V supply, the measured oscillation frequency is from 9.25 GHz to 12.08 GHz, translating into a tuning range of 26.6%, as the control voltage is swept from 0 V to 1.8 V. At 1-MHz offset, the minimum phase noise and FoM are −116.3 dBc/Hz and −182.7 dBc/Hz, respectively. With the frequency tuning range, the output power is 8±0.4 dBm, the DC power consumption of the VCO core is less than 17.37 mW, and the detected output voltage is 60±20 mV. In this work, a 60-GHz QVCO for digital home application is designed and measured. In addition, a VCO with built-in envelop detector is designed and measured. The relation between its detector output voltage and output power is found, demonstrating its potential for RF BIST.