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一种用于塑料光纤接入网的多优先级控制协议设计 总被引:8,自引:4,他引:4
提出一种基于光码分多址(OCDMA)技术的塑料光纤接入网的多优先级控制协议.由于受传输误码率的限制,常规的光码分多址系统只允许有限个用户传输数据或接入网络,为了解决用有限的码字来实现多于码字数目的多媒体工作站间的信息通信,这种多优先级的控制协议通过使用预约和随机分配算法可以有效地解决信道冲突和目的地址的冲突问题, 该协议可以支持多媒体信息传输中各类信息不同的时间延迟要求.另外,在该接入网中,每个光网络单元均设有两套光编码器和光解码器,一套用于控制信道,另一套用于各个数据信道.利用本文提出的协议对塑料光纤接入网的网络吞吐量和平均延时时间进行了数值分析和仿真实验,结果证明了这种多优先级控制协议的有效性和高效性. 相似文献
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In this paper, a novel multipriority reservation protocol for plastic optical fiber access network based on optical code division multiplexing access (OCDMA) technology is proposed. Conventional OCDMA system only allows finite units to transmit and access simultaneously according to the number of channels. The protocol is proposed to resolve this problem. By using the reservation scheme and a distributed arbitration algorithm, channel collision and destination conflict can be avoided. The protocol can efficiently support the transmission of multimedia messages that require the different time-delays. At the same time, each optical network unit is equipped with a fixed optical encoder/decoder that is always tuned to channel for control and the tunable optical encoder/decoder that is tuned to any of channel for data. The network throughput and average delay have been investigated by numerical analysis and simulation experiments. It is shown that the multipriority reservation protocol in this POF access net 相似文献
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The loss properties of air-core plastic photonic bandgap fibers are analyzed by multipole method. Despite the relatively large absorption loss of plastics (PMMA), the contribution of material absorption loss can be reduced significantly through appropriate selection of operating wavelength, number of cladding air-hole rings, radius of air-core, and position of photonic band gap. The transmission loss in this type of fiber can be decreased by an order of magnitude in comparison with that of conventional plastic optical fiber. 相似文献
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多模梯度折射率塑料光纤带宽的分析 总被引:3,自引:3,他引:0
结合WKB法对多模梯度折射率塑料光纤(GI-POF)色散和带宽进行了综合分析,研究了在GI-POF中材料色散对带宽影响的程度和规律,给出较佳折射率指数(g)的范围,并说明实测带宽高于理论带宽的原因. 相似文献