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本文介绍了I^2C串行总线控制器PCF8584的结构、功能。结合我们一个课题,给出了PCF8584在系统中的应用。 相似文献
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Photonic crystal fibers (PCFs) present a wavelength-scale periodic microstructure along their length.Their core and two-dimensional photonic crystal might be based on varied geometries and materials,al... 相似文献
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Multiple access control (MAC) protocols play a significant role in wireless LANs. The IEEE 802.11 MAC protocol specifies two
coordination functions that are Distributed Coordination Function (DCF) and Point Coordination Function (PCF). While both
DCF and PCF are available in a wireless cell, we propose a novel access mechanism called Adaptive Coordination Function (ACF)
to support various classes of traffic. The ACF superframe comprises two periods, one TDMA period designed for real-time traffic
and followed by an adaptive period which adaptively employs DCF or PCF to support non-real-time traffic. In this paper, we
apply the theory of M/G/1 queues to analyze the performance of adaptive period in terms of queuing delay, end-to-end delay,
and saturation throughput. With our analytic model, DCF or PCF can be invoked appropriately according to the number of stations,
packet arrival rate, packet payload size, and effective channel bit rate. Analytical results are derived for an extensive
throughput and delay performance evaluation of both DCF and PCF. 相似文献
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Bhawana Dabas 《Optics Communications》2011,284(5):1186-1191
In this article, a new simplified structure of a highly birefringent chalcogenide As2Se3 glass photonic crystal fiber (PCF) is designed and analyzed by using fully vectorial finite element method. The effective indices, confinement loss, birefringence, and chromatic dispersion of fundamental polarized mode are calculated in the proposed PCF for a wide wavelength range. To maintain the polarization in chalcogenide As2Se3 glass PCF, we enlarged two of the central air holes and reduced two transverse air holes for achieving high birefringence. This helps in creating an effective index difference between the two orthogonal polarization modes. It is also shown that As2Se3 glass PCF provides lower chromatic dispersion and less confinement loss compared to silica PCF of the same structure in wavelength range 1.3 to 1.8 μm and hence such chalcogenide As2Se3 glass PCF have high potential to be used in dispersion compensating and birefringence application in optical communication systems. In addition to this, the polarization mode dispersion (PMD) result of the proposed PCF is also reported. 相似文献
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1 Introduction Fiber lasers have been developed for more than forty years since Snitzer!s proposal and the demonstration of Nd- doped fiber in 1961 [1]. But fiber lasers have not been attracted considerable attention until the develop- ment of the low- loss fiber fabrication technology and the high power semiconductor laser technology recently. Actually,it is the application and development of fiber communication technology that has promoted the rapid development of fiber laser. Fiber laser, … 相似文献
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利用高非线性光子晶体光纤中的自相位调制效应产生的超连续谱,理论上推导了超窄脉冲信号的再生机制。分别从频域和时域上形象的解释了脉冲再生的原理,该本再生方法可以适用于OTDM的信号再生。实验上对劣化了的脉冲宽度为1.7ps的携带信息的超窄脉冲信号进行了再生,再生之后的信号峰值均衡,消光比达到了15dB。再生前信号中心波长是1548.2nm,重复频率是9.96872GHz。实验中,在1554nm—1570nm和1530nm—1543nm范围内都可以得到10dB以上的再生质量。同时拟合了信号峰值功率和波长关系,得到的曲线和超连续谱曲线相吻合。 相似文献
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