Compact transmitter and receiver optical sub-assemblies(TOSA and ROSA) are fabricated in our laboratory and have an aggregated capacity of 100 Gb/s. Specially, directly modulated laser(DML) drivers with two layers...Compact transmitter and receiver optical sub-assemblies(TOSA and ROSA) are fabricated in our laboratory and have an aggregated capacity of 100 Gb/s. Specially, directly modulated laser(DML) drivers with two layers of electrical circuit boards are designed to inject RF signals and bias currents separately. For all the lanes, the3 dB bandwidth of the cascade of the TOSA and ROSA exceeds 9 GHz, which allows the 12.5 Gb/s operation.With the 12.5 Gb/s × 8-lane operation, clear eye diagrams for back-to-back and 30-km amplified transmission with a dispersion compensation fiber are achieved. Low cost and simple processing technology make it possible to realize commercial production.展开更多
The bonded distributed feedback(DFB) fiber laser(FL) acoustic emission sensor and the intensity response of the DFB-FL to external acoustic emissions are investigated. The dynamic sensitivity of the DFB-FL is cali...The bonded distributed feedback(DFB) fiber laser(FL) acoustic emission sensor and the intensity response of the DFB-FL to external acoustic emissions are investigated. The dynamic sensitivity of the DFB-FL is calibrated by a referenced piezoelectric receiver. In the DFB-FL we used here, the minimum detectable signal is2 × 10^(-6)m∕s at 5 kHz. Using wavelet packet technology, the collected signals are analyzed, which confirms that an intensity-modulated DFB-FL sensor can be used to detect acoustic emission signals.展开更多
This paper explores an energy-efficient pulsed ultra-wideband(UWB) radio-frequency(RF) front-end chip fabricated in 0.18-μm CMOS technology, including a transmitter, receiver, and fractional synthesizer. The tran...This paper explores an energy-efficient pulsed ultra-wideband(UWB) radio-frequency(RF) front-end chip fabricated in 0.18-μm CMOS technology, including a transmitter, receiver, and fractional synthesizer. The transmitter adopts a digital offset quadrature phase-shift keying(O-QPSK) modulator and passive direct-phase multiplexing technology, which are energy-and hardware-efficient, to enhance the data rate for a given spectrum.A passive mixer and a capacitor cross-coupled(CCC) source-follower driving amplifier(DA) are also designed for the transmitter to further reduce the low power consumption. For the receiver, a power-aware low-noise amplifier(LNA) and a quadrature mixer are applied. The LNA adopts a CCC boost common-gate amplifier as the input stage, and its current is reused for the second stage to save power. The mixer uses a shared amplification stage for the following passive IQ mixer. Phase noise suppression of the phase-locked loop(PLL) is achieved by utilizing an even-harmonics-nulled series-coupled quadrature oscillator(QVCO) and an in-band noise-aware charge pump(CP) design. The transceiver achieves a measured data rate of 0.8 Gbps with power consumption of 16 m W and31.5 m W for the transmitter and the receiver, respectively. The optimized integrated phase noise of the PLL is0.52° at 4.025 GHz.展开更多
基金supported by the National High-Tech Research and Development Program of China(No.2013AA014201)the National Natural Science Foundation of China(Nos.61575186 and 61635001)
文摘Compact transmitter and receiver optical sub-assemblies(TOSA and ROSA) are fabricated in our laboratory and have an aggregated capacity of 100 Gb/s. Specially, directly modulated laser(DML) drivers with two layers of electrical circuit boards are designed to inject RF signals and bias currents separately. For all the lanes, the3 dB bandwidth of the cascade of the TOSA and ROSA exceeds 9 GHz, which allows the 12.5 Gb/s operation.With the 12.5 Gb/s × 8-lane operation, clear eye diagrams for back-to-back and 30-km amplified transmission with a dispersion compensation fiber are achieved. Low cost and simple processing technology make it possible to realize commercial production.
基金supported by the National 863 Program of China(No.2014AA093406)the Youth Innovation Promotion Association of CAS(No.2016106)+1 种基金the Project of Observation Instrument Development for Integrated Geophysical Field of China Mainland(No.Y201606)the Key Project of Hebei Educational Committee(No.BJ2016048)
文摘The bonded distributed feedback(DFB) fiber laser(FL) acoustic emission sensor and the intensity response of the DFB-FL to external acoustic emissions are investigated. The dynamic sensitivity of the DFB-FL is calibrated by a referenced piezoelectric receiver. In the DFB-FL we used here, the minimum detectable signal is2 × 10^(-6)m∕s at 5 kHz. Using wavelet packet technology, the collected signals are analyzed, which confirms that an intensity-modulated DFB-FL sensor can be used to detect acoustic emission signals.
基金Project supported by the National Science and Technology Major Project of China(No.2011ZX03004-002-01)
文摘This paper explores an energy-efficient pulsed ultra-wideband(UWB) radio-frequency(RF) front-end chip fabricated in 0.18-μm CMOS technology, including a transmitter, receiver, and fractional synthesizer. The transmitter adopts a digital offset quadrature phase-shift keying(O-QPSK) modulator and passive direct-phase multiplexing technology, which are energy-and hardware-efficient, to enhance the data rate for a given spectrum.A passive mixer and a capacitor cross-coupled(CCC) source-follower driving amplifier(DA) are also designed for the transmitter to further reduce the low power consumption. For the receiver, a power-aware low-noise amplifier(LNA) and a quadrature mixer are applied. The LNA adopts a CCC boost common-gate amplifier as the input stage, and its current is reused for the second stage to save power. The mixer uses a shared amplification stage for the following passive IQ mixer. Phase noise suppression of the phase-locked loop(PLL) is achieved by utilizing an even-harmonics-nulled series-coupled quadrature oscillator(QVCO) and an in-band noise-aware charge pump(CP) design. The transceiver achieves a measured data rate of 0.8 Gbps with power consumption of 16 m W and31.5 m W for the transmitter and the receiver, respectively. The optimized integrated phase noise of the PLL is0.52° at 4.025 GHz.