- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Flattop output extra-wide tuning range tunable laser design technique
摘要： The laser oscillator design principle, which provides extended tunability together with a flattop output in the wide spectral range, is proposed and demonstrated on the examples of the dye laser. It is realized by using an high-reflecting (HR) moving intracavity mirror (scraper) with the sharp edge partially overlapping the laser radiation in the high-Q cavity and extracting it out. The technique provides the output laser beam with M2 < 1.2 and can be applied to any type of lasers operating from the far-IR to the VUV spectral ranges. Besides, wide-band HR cavity mirrors are only used, and there are no special demands to the material of the mirror substrate.
关键词： laser efficiency,output coupler optimization,tunable lasers
更新于2025-09-23 15:19:57
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[IEEE 2019 34th Symposium on Microelectronics Technology and Devices (SBMicro) - Sao Paulo, Brazil (2019.8.26-2019.8.30)] 2019 34th Symposium on Microelectronics Technology and Devices (SBMicro) - Effect of the dopant location and the number of Bragg mirrors on the performance of superlattice infrared photodetectors
摘要： This paper presents a substrate integrated waveguide Butler matrix with a modi?ed hybrid coupler, operating from 28 to 32 GHz. The modi?ed hybrid coupler is realized by using 90? hybrid coupler followed by a ?45? compensating phase shifter. Thus, 45?/135? output phase differences can be obtained using this type of coupler. Compared with the equal-length unequal-width phase shifter, the compensating phase shifter exhibits better phase characteristics, with only 3? phase error over 28–32 GHz. Because the phase of compensating phase shifter is not realized by taking the phase introduced by the crossover as a reference, it gives great ?exibility to the design of compensating phase shifter. Adopting the modi?ed hybrid coupler, the designed Butler matrix features the output phases with peak to peak error of 13? and wideband performance from 28 to 32 GHz. The slot array fed by the Butler matrix can radiate four slanted beams with acceptable measured gains, in the range of 9.7～12 dBi for port 1 excitation and 8.4～11.1 dBi for port 2 excitation. The radiated beams can reach a wide azimuthal coverage between ±61?.
关键词： Butler matrix,Modi?ed hybrid coupler,substrate integrated waveguide (SIW),compensating phase shifter,slot array antenna
更新于2025-09-23 15:19:57
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Characteristic Test Analysis of Graphene Plus Optical Microfiber Coupler Combined Device and Its Application in Fiber Lasers
摘要： In this study, a graphene and optical microfiber coupler (OMC) integrated device (GOMC) was proposed and fabricated. After its characteristic analysis and testing, it was applied to the development of adjustable multi-wavelength fiber lasers. By integrating the OMC with graphene, the polarization dependence of OMC was enhanced. Meanwhile, the novel GOMC was given the capabilities of filtering, coupling, beam splitting, and polarization correlation. When the GOMC was integrated as a filter and beam splitter into the ring cavity of the fiber laser, the proposed GOMC-based fiber laser could achieve single-wavelength and multi-wavelength regulated output. The laser had a 3 dB linewidth of less than 30 pm, a signal-to-noise ratio of approximately 40 dB, and an output power fluctuation of less than 1 dB. The GOMC could also be used for the development of functional devices, such as adjustable mode lockers and mode coupling selectors, which provide an excellent experimental platform for new fiber lasers and the research of multi-dimensional light-field manipulation.
关键词： filter,optical microfiber coupler,graphene,fiber laser
更新于2025-09-23 15:19:57
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[IEEE 2018 Eighth International Conference on Instrumentation & Measurement, Computer, Communication and Control (IMCCC) - Harbin, China (2018.7.19-2018.7.21)] 2018 Eighth International Conference on Instrumentation & Measurement, Computer, Communication and Control (IMCCC) - Research on Internal Temperature of Transformer Internal Temperature Based on Optical Fiber Sensing Technology
摘要： Transformer is an important link of power system, and its operation state directly affects the security and stability of power system operation. With the continuous development of the national economy and the continuous improvement of the people's needs, the power grid load has been continuously improved, and the capacity of the transformer has been continuously expanded, and the accident rate has increased accordingly. According to related statistics, more than 66 kv transformer of the world's average accident rate over 0.89%, especially for winding in transformer winding overtemperature operation, result insulation aging and breakdown, accident of burning large ratio (according to the statistics, about 80% of the accident rate above). For oil-immersed power transformer, the time depends on the service life of solid insulating materials (fiber paper), prompting insulation materials is the main factor of aging temperature, moisture and oxygen, heat effect of transformer insulation aging is the decisive factor, therefore the transformer internal main parts (winding and iron core, the place such as insulating oil) temperature decides the service life of the transformer temperature due to the electric power equipment testing environment with high voltage and strong electromagnetic interference, and space is narrow, the traditional method cannot directly on the power equipment temperature state of online measurement, and a new temperature measuring system based on semiconductor optical fiber sensing technology has small volume, good insulation, good resistance to electromagnetic interference, temperature measurement consistency, can be directly installed on the transformer and other power equipment inside, can accurate and fast reflect the change of the internal temperature of main components of power transformer, the transformer winding and iron core, the place such as insulating oil temperature real-time online measurement.
关键词： Fiber coupler,Fiber Bragg grating,F-P filter,transformer
更新于2025-09-23 15:19:57
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Wide-Band Filtering Three-Port Coupler with Inherent DC-Blocking Function
摘要： This paper presents a novel wide-band filtering three-port coupler with inherent DC-blocking function, which is simply comprised of a power divider with wideband filtering function and a broadband phase shifter with a modified coupled line. For demonstration, a designed prototype operating at 3 GHz is simulated, fabricated, and measured. From the simulated and measured results, the coupler shows a 49% filtering bandwidth with 12-dB return loss and 90±5° phase shifting. The amplitude imbalance between the two output ports is less than 0.5 dB. The all-passband isolation is below -13 dB and the 25.7-dB upper stopband rejection is up to 5.4 GHz. The good agreement between the simulated and measured results validates the proposed idea. Hence, the proposed coupler is well suited for applications of wideband, filtering, and single-layer circuitry integration.
关键词： filtering,power divider,DC-blocking,phase shifter,wideband,Coupler
更新于2025-09-19 17:15:36
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High-Sensitivity Loop-Fiber Temperature Sensor Based on Distilled Water Cladding
摘要： The study proposed a temperature sensor based on distilled water cladding of the coupling region in the loop-?ber coupler, which was formed by folding a single-mode ?ber, melting the taper region with an H2 ?ame, and using two adjacent ?bers to obtain the interference in the coupling. Based on thermo-optical effect response and coupling interference principle, with increasing ambient temperature, the refractive index of the distilled water decreased, and the interference spectrum drifted. The experiment explored the relationship between different lengths of taper region and interference spectrum. When the taper region length was 30–35 mm, the interference spectrum improved. Results showed that the maximum sensitivity of the sensor was 151.35 pm/°C and linearity reached 99.99% when the temperature was within the range of 35 °C to 60 °C. Furthermore, we propose a low-cost demodulation scheme. The sensor had high sensitivity, good linearity, good stability, fast response, simple manufacturing process, and low cost. It has potential application value.
关键词： Loop-?ber coupler,Thermo-optical effect,Evanescent ?eld,Temperature sensor
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Rapid Recovery of CIGS Solar Cells from PID Stress with Light Soaking
摘要： This paper presents a substrate integrated waveguide Butler matrix with a modi?ed hybrid coupler, operating from 28 to 32 GHz. The modi?ed hybrid coupler is realized by using 90? hybrid coupler followed by a ?45? compensating phase shifter. Thus, 45?/135? output phase differences can be obtained using this type of coupler. Compared with the equal-length unequal-width phase shifter, the compensating phase shifter exhibits better phase characteristics, with only 3? phase error over 28–32 GHz. Because the phase of compensating phase shifter is not realized by taking the phase introduced by the crossover as a reference, it gives great ?exibility to the design of compensating phase shifter. Adopting the modi?ed hybrid coupler, the designed Butler matrix features the output phases with peak to peak error of 13? and wideband performance from 28 to 32 GHz. The slot array fed by the Butler matrix can radiate four slanted beams with acceptable measured gains, in the range of 9.7～12 dBi for port 1 excitation and 8.4～11.1 dBi for port 2 excitation. The radiated beams can reach a wide azimuthal coverage between ±61?.
关键词： Butler matrix,Modi?ed hybrid coupler,substrate integrated waveguide (SIW),compensating phase shifter,slot array antenna
更新于2025-09-19 17:13:59
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[IEEE 2019 12th UK-Europe-China Workshop on Millimeter Waves and Terahertz Technologies (UCMMT) - London, United Kingdom (2019.8.20-2019.8.22)] 2019 12th UK-Europe-China Workshop on Millimeter Waves and Terahertz Technologies (UCMMT) - A 400 GHz Broadband Multi-Branch Waveguide Coupler
摘要： Terahertz (THz) technology is a hotspot in current academic research. A 400 GHz broadband Multi-branch waveguide hybrid coupler is designed in this paper. Compared to 5-branch designs, the proposed hybrid consists of 7-branch and has been optimized to a great performance, which increases the operation bandwidth. Based on this model, the performance of the mixer is optimized by HFSS software. The simulation results show that the return loss (S11) and isolation (S23) are better than 20 dB in the frequency range of 350 GHz to 450 GHz, which is nearly 25% relative bandwidth, and the good performance of power splitting can also be seen from the amplitude and phase of S21 and S31.
关键词： passive circuit,broadband capabilities,Terahertz,3dB waveguide hybrid coupler
更新于2025-09-19 17:13:59
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[IEEE 2018 11th UK-Europe-China Workshop on Millimeter Waves and Terahertz Technologies (UCMMT) - HangZhou, China (2018.9.5-2018.9.7)] 2018 11th UK-Europe-China Workshop on Millimeter Waves and Terahertz Technologies (UCMMT) - Investigation of Ultra-wideband Ridged Half-Mode Substrate-Integrated Waveguide Coupler
摘要： In this paper, a novel ultra wideband (UWB) 3-dB coupler at X and Ku band based on ridged half-mode substrate integrated waveguide (RHMSIW) and embedded the shape of metal groove is designed, fabricated, and measured, which is widely used in microwave and millimeter wave circuits. The structural parameters of new UWB RHMSIW 3-dB coupler with three cascading metal groove cells are analyzed. The structure is simulated with a relative bandwidth of 48% at the center frequency of 15 GHz. The measured results show that the proposed RHMSIW coupler keeps good performance of the HMSIW coupler. Simulated results are in agreement with the measured results. The results show that the novel UWB RHMSIW 3-dB coupler can provide better performance and have a smaller size compared with reported couplers, which illustrates its application in the wideband millimeter wave systems.
关键词： metal groove,ultra wideband,coupler,Ridged half-mode substrate integrated waveguide (RHMSIW)
更新于2025-09-19 17:13:59
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[IEEE 2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Guangzhou, China (2019.5.19-2019.5.22)] 2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Wideband Coupler Based on Wide-Wall Coupling Half-Mode Ridge Substrate Integrated Waveguide
摘要： A wideband coupler based on half-mode ridge substrate integrated waveguide (HMRSIW) is designed in this paper. The coupler utilizes a gradual slot on wide-wall to couple. The measured coupling bandwidth is 49.8%. The return loss and isolation are better than 20dB from 11.76GHz to 17.88GHz.
关键词： half-mode ridge substrate integrated waveguide,HMRSIW,Ku-band,wideband coupler
更新于2025-09-19 17:13:59