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针对光纤Mach-Zehnder干涉(MZI)受环境影响的稳定性问题,设计了光纤MZI实验装置。从理论上分析了光纤MZI的输出光强,并给出了实验验证,由示波器直观地显示出光纤MZI的稳定性与环境的关系以及相位调制对干涉的影响等。为了解决振动噪声、温度变化等环境因素导致的光纤MZI不稳定,设计了一种新的相位补偿方案,即用两个2×2光纤耦合器的输出,实现相差检测及反馈控制。 相似文献
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光纤光栅振动传感解调方法的研究 总被引:12,自引:0,他引:12
光纤光栅振动传感是光纤光栅的重要应用之一。本文首先介绍了光纤光栅传感的一般原理,接下来综述了5种常用的振动传感的解调方法及原理,并分别给出了其典型的实验装置结构图,分析了其特点和性能(尤其是测量精度),为基于光纤光栅的振动传感装置的解调部分的设计提供了依据。 相似文献
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针对贯穿密闭容器的抗高压光纤气密封转接装置,通过改进转接装置制作工艺,采用裸光纤灌胶密封,设计两端带光纤定位套保护的灌胶筒,灌封胶分次注入等措施,有效地降低了密封转接装置对传输光信号的衰减。检测结果表明:所研制的抗压低衰减光纤气密封转接装置实验样品,在满足密闭容器超压冲击实验密封要求(容器内外压差2MPa,气体漏率小于10-7 Pa·m3/s)的情况下,在密封转接段的光信号衰减小于1dB。 相似文献
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数值孔径NA(Numerical Aperture)是通信光纤的一个重要光学参数,表征了光纤的集光能力.它与光纤传输系数的计量有密切关系,对通信光纤的传输带宽有很大影响.光纤数值孔径的测量方法有多种,文中设计了一种用于通信光纤数值孔径快速测量的装置,该装置包括光源、刻度旋转台、微调机构及数字仪表等单元,测量基于光斑光强渐变机理,根据仪表显示值在临界点突变可确定被测光纤的数值孔径,实验表明该装置测量稳定可靠,多次测量平均值的重复性优于2%. 相似文献
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一种可调谐掺铒光纤激光器的研究 总被引:1,自引:0,他引:1
文章基于掺铒光纤在1 550 nm波段的增益特性,利用光纤光栅作为调谐装置,设计了可调谐光纤光栅激光器的简单结构,通过改变光纤光栅的温度对光纤激光嚣的波长进行了调谐.更重要的是实验分析了不同掺铒光纤长度对激光输出功率的影响,在温度为25℃时,实验中分别取10、20和30 m 3种不同光纤长度进行了测试,结果表明,不同长度的掺铒光纤,其阀值不同. 相似文献
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设计了一种新型高温传感装置,将一段七芯光纤耦合在两段单模光纤之间,发射光进入到七芯光纤中,在透射光谱范围内产生周期性调制的超模干涉图案,其频谱偏移随温度变化而改变,实现了实时监测.该传感装置制造简单,实验证明在温度高达1000℃的环境下仍可稳定工作. 相似文献
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Dong-Woo Kang Songcheol Hong 《Microwave Theory and Techniques》2007,55(7):1476-1483
This paper presents a novel 4-bit phase shifter using distributed active switches in 0.18-mum RF CMOS technology. The relative phase shift, which varies from 0deg to 360deg in steps of 22.5deg, is achieved with a 3-bit distributed phase shifter and a 180deg high-pass/low-pass phase shifter. The distributed phase shifter is implemented using distributed active switches that consist of a periodic placement of series inductors and cascode transistors, thereby obtaining linear phase shift versus frequency with a digital control. The design guideline of the distributed phase shifter is presented. The 4-bit phase shifter achieves 3.5 plusmn 0.5 dB of gain, with an rms phase error of 2.6deg at a center frequency of 12.1 GHz. The input and output return losses are less than -15 dB at all conditions. The chip size is 1880 mum times 915 mum including the probing pads. 相似文献
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We describe a frequency domain detection scheme of coherence multiplexed sensor signals by using an optical loop with a frequency shifter. The optical path differences of the sensors are adjusted to integer-multiple of the loop length of the optical loop, and then the the sensor signals are multiplexed in the frequency domain, appearing at the integer-multiple of the working frequency of the frequency shifter. In the experiment, four Michelson-type sensors are successfully multiplexed with the sensitivities of about 2 mrad/√Hz. The sensitivities are also theoretically calculated which are in good agreement with the experimental results. The optimum design of the optical loop is also discussed 相似文献
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介绍了数字移相器的基本原理及设计方法。在ADS仿真环境下,基于GaAs HJ—FET开关器件,设计仿真了一种X波段五位数字移相器,大大降低了移相器的后期制作成本。利用矢量网络分析仪对制作的实物进行了测试,结果表明:在12—12.5GHz频段内,移相器的最大插损小于9.5dB,均方根相位误差在3°以内。 相似文献
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Qi-Lin Qiu Xiao-Peng Yu Wen-Quan Sui 《Journal of Infrared, Millimeter and Terahertz Waves》2017,38(11):1368-1386
In this paper, the design challenges of the injection-locked oscillator (ILO)-based phase shifter are reviewed and analyzed. The key design considerations such as the operating frequency, locking range, and linearity of the phase shifters are analysed in detail. It is possible to optimize the phase shifter in certain parameters such as ultra-low power while meeting the requirements of a certain system. As a design example, a K-band phase shifter is implemented using a commercial 0.13 μm CMOS technology, where a conventional LC tank based topology is implemented but optimised with a good balance among power consumption, working range, sensitivity, and silicon area, etc. Measurement results show that the proposed phase shift is able to work at 22–23.4 GHz with a range of 180° while consuming 3.14 mW from a 1.2 V supply voltage. 相似文献
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This paper presents wideband compact differential reflective phase shifter based on the double layer slot-coupled coupler configuration. This novel phase shifter arrangement consists of a 3-dB hybrid coupler with the coupled and transmission ports terminated with rectangular and elliptically shaped microstrip loads. By altering the ports termination of the coupler, phase shifters propose differential phase ranging from −90° to +90° over 1.3–5.9G Hz frequency band. To achieve different range of phase performance, the proper reactance is calculated at the outputs of coupler. These reactances are transformed to the elliptical or rectangular-shaped microstrip load with various dimensions for every phase shifter. The calculation and simulations results show that the developed circuits could provide ±30°, ±60°, ±45° and ±90° differential phase shifts. For verification of this wideband phase shifter design method, two phase shifter example with rectangular and elliptical load termination is fabricated and measured. The measured return loss of the phase shifter with elliptically load is better than 10 dB over 1.3–5.9G Hz frequency band as well as insertion loss is less than 1 dB. The phase shift deviation is less than 2.1°. The results demonstrate that the proposed phase shifters are well suited for use in GPS/LTE/WiMax/WLAN frequency bands. 相似文献
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We present a 135deg/45deg phase shifter hybrid intended to be used in subharmonic sideband separation mixer schemes at submillimeter-wave frequencies. The design consists of an increased height 90deg 6-arm branch guide coupler with a three stub loaded differential line 45deg phase shifter at the output. The device has been implemented at G-band in an E-plane WR-05 splitblock design with a center frequency of 170 GHz and 15 % bandwidth. Measured S-parameter are in good agreement with simulations showing an isolation and return loss better than 20 dB and an amplitude and phase imbalance within 0.4 dB and 2deg, respectively. 相似文献
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Distributed MEMS analog phase shifter with enhanced tuning 总被引:1,自引:0,他引:1
The design, fabrication, and measurement of a tunable microwave phase shifter is described. The phase shifter combines two techniques: a distributed capacitance transmission line phase shifter, and a large tuning range radio frequency (RF) microelectromechanical system (MEMS) capacitor. The resulting device is a large bandwidth, continuously tunable, low-loss phase shifter, with state-of-the-art performance. Measurements indicate analog tuning of 170/spl deg/ phase shift per dB loss is possible at 40 GHz, with a 538/spl deg/ phase shift per centimeter. The structure is realized with high-Q MEMS varactors, capable of tuning C/sub max//C/sub min/= 3.4. To our knowledge, this presents the lowest loss analog millimeter wave phase shifter performance to date. 相似文献
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设计并研制了一种6~11GHz、超宽带5位RF MEMS开关延迟线移相器,器件实现了5位延迟:λ、2λ、4λ、8λ、16λ。该器件采用微带混合介质多层板技术,分4层制作,尺寸为45mm×20 mm。整个器件包括20个RFMEMS悬臂梁开关,用60~75V的静电压驱动。6~11GHz频带内,对32个相移态的测试结果表明:一般回波损耗S11<-10dB,各状态平均插入损耗为-8~-10dB;中心频率处,器件可实现的最大延迟位时延为1680ps,总时延为3255ps。 相似文献