A direction related polarizer (DRP) was used in a laser cavity to eliminate spatial hole burning of gain medium in a bidirectional Er-doped fiber ring laser. A stable operation of single longitudinal mode was achieved...A direction related polarizer (DRP) was used in a laser cavity to eliminate spatial hole burning of gain medium in a bidirectional Er-doped fiber ring laser. A stable operation of single longitudinal mode was achieved with comparable intensities for both clockwise and counterclockwise direction. A beat signal of 30 dB over noise was observed. This laser used as a gyroscope was demonstrated and a good linear relation between the beat frequency shift and the cavity rotation rate was acquired.展开更多
A direction related polarizer was inserted into a ring laser cavity to eliminate one of the two eigen-modes as well as spatial hole burning of the gain medium in a bidirectional Er-doped fiber ring laser. Thus, a fibe...A direction related polarizer was inserted into a ring laser cavity to eliminate one of the two eigen-modes as well as spatial hole burning of the gain medium in a bidirectional Er-doped fiber ring laser. Thus, a fiber ring laser gyroscope （FRLG） operating in continuous wave was demonstrated. A beat signal of over 30-dB noise was observed and a good linear relation between the beat frequency shift and cavity rotation rate was obtained.展开更多
A high performance quadrature voltage-controlled oscillator （QVCO） is presented. It has been fabricated in SMIC 0.18 μm CMOS technology with top thick metal. The proposed QVCO employed cascade serial coupling for i...A high performance quadrature voltage-controlled oscillator （QVCO） is presented. It has been fabricated in SMIC 0.18 μm CMOS technology with top thick metal. The proposed QVCO employed cascade serial coupling for in phase and quadrature phase signal generation. Source degeneration capacitance is added to the NMOS differential pair to suppress their flicker noise from up-conversion to close in phase noise. A dedicated low noise and high power supply rejection low drop out regulator is used to supply this QVCO. The measured phase noise of the proposed QVCO achieves phase noise of-123.3 dBc/Hz at an offset frequency of 1 MHz from the carrier of 4.78 GHz, while the QVCO core circuit and LDO draw 6 mA from a 1.8 V supply. The QVCO can operate from 4.09 to 4.87 GHz （17.5%）. Measured tuning gain of the QVCO （Kvco） spans from 44.5 to 66.7 MHz/V. The chip area excluding the pads and ESD protection circuit is 0.41 mm2.展开更多
文摘A direction related polarizer (DRP) was used in a laser cavity to eliminate spatial hole burning of gain medium in a bidirectional Er-doped fiber ring laser. A stable operation of single longitudinal mode was achieved with comparable intensities for both clockwise and counterclockwise direction. A beat signal of 30 dB over noise was observed. This laser used as a gyroscope was demonstrated and a good linear relation between the beat frequency shift and the cavity rotation rate was acquired.
文摘A direction related polarizer was inserted into a ring laser cavity to eliminate one of the two eigen-modes as well as spatial hole burning of the gain medium in a bidirectional Er-doped fiber ring laser. Thus, a fiber ring laser gyroscope （FRLG） operating in continuous wave was demonstrated. A beat signal of over 30-dB noise was observed and a good linear relation between the beat frequency shift and cavity rotation rate was obtained.
基金supported by the Ministry of Industry and Information Technology of China(No.2009ZX03006-009)
文摘A high performance quadrature voltage-controlled oscillator （QVCO） is presented. It has been fabricated in SMIC 0.18 μm CMOS technology with top thick metal. The proposed QVCO employed cascade serial coupling for in phase and quadrature phase signal generation. Source degeneration capacitance is added to the NMOS differential pair to suppress their flicker noise from up-conversion to close in phase noise. A dedicated low noise and high power supply rejection low drop out regulator is used to supply this QVCO. The measured phase noise of the proposed QVCO achieves phase noise of-123.3 dBc/Hz at an offset frequency of 1 MHz from the carrier of 4.78 GHz, while the QVCO core circuit and LDO draw 6 mA from a 1.8 V supply. The QVCO can operate from 4.09 to 4.87 GHz （17.5%）. Measured tuning gain of the QVCO （Kvco） spans from 44.5 to 66.7 MHz/V. The chip area excluding the pads and ESD protection circuit is 0.41 mm2.
