共查询到19条相似文献,搜索用时 109 毫秒
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通常,在串口通信中协议数据帧在线路上的传输会受各种干扰而出错,其可靠性比较差,而且容错纠错能力低,而该串口通信协议却能够在基于串口的通信线路上保证了协议数据帧的高可靠性传输,并已经将此串口通信协议运用在一些装备中,实践中也进行了充分的验证。 本文讲述了该串口通信协议的协议数据帧格式,其协议数据帧格式中包含起始标志字段、长度字段、序列号字段、地址字段、应用数据字段、CRC16 校验字段、结束标志字段,这种协议数据帧格式设计保证了应用数据能够在线路中进行高可靠性地传输。本文还对该协议数据帧的组帧、收发和解析做了描述,并且还对该协议数据帧的丢失进行了判断与处理,大大提高了该串口通信协议的可靠性、实时性和容错性。 相似文献
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基于Qt的多串口多协议数据接收解析软件的设计与实现 总被引:1,自引:0,他引:1
该文讨论了基于Visual Sudio2005/Qt集成环境下,多串中多协议的数据帧接收解析软件的设计与实现.实现动态选择多路串口数据帧或信号,并把选择的数据帧或信号根据相应的协议描述文件在串口类对象进行断帧、解析.该软件具有数据帧描述协议可设置、数据帧硬件配置可设置、良好的人机交互性等优点. 相似文献
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为提高帧内刷新算法的抗传输差错能力,提出了一种基于运动跟踪的帧内刷新算法。首先,在相邻两个帧内刷新帧之间对运动影响区域内的宏块进行统计分析,选取对传输差错敏感的宏块进行帧内刷新。其次,对刷新帧后的帧间预测帧进行参考特性限制,进一步防止传输差错在帧内和帧间的扩散。实验结果表明,在多种丢包环境下,该算法与自适应帧内刷新算法相比,重建图像的峰值信噪比(PSNR)平均提高1 dB以上,主观质量明显提高,且运算复杂度低。 相似文献
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《无线电通信技术》2016,(4)
为降低测控通信系统延迟对无人飞行器性能影响,在深入分析影响测控通信视频编码传输延迟基础上,提出了一种适合于测控通信传输的低时延视频编码传输帧结构。算法引入帧内刷新编码方式将I帧码流平均到其他P帧中,使得压缩后各帧编码码流尽可能得到平均,从而减少编码发送缓冲区延迟;根据slice编码方式的独立性将一帧图像分成多个slice并行编码模式以减少编码处理延迟;同时去除双向预测编码B帧模式以减少帧排序延迟。实验采用新一代HEVC标准进行仿真分析,结果表明算法在不明显降低视频编码质量前提下,使得压缩后各帧码流大小尽可能平均,有效地减少了测控通信系统中视频压缩传输延迟。 相似文献
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基于ZigBee的无线传感器网络研究 总被引:4,自引:1,他引:3
为了验证ZigBee协议的有效性,叙述了新型无线ZigBee通信技术,介绍ZigBee协议的结构和特点,基于ZigBee协议的无线网络设备以及网络拓扑结构;ZigBee标准协议栈结构及数据在协议栈内部的传输机制。以两个网络设备成网为例,详细给出了ZigBee设备形成网络时,各个设备的工作状态、设备之间网络连接过程以及数据帧的发送过程。最后,通过Microchip公司的ZigBee实验平台验证了ZigBee无线星型组网,实验证明,ZigBee技术是有效的无线传感器网络组网技术。 相似文献
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We present a hardware/software implementation of the IEEE 802.15.3 MAC protocol. Processing-intensive and time-critical protocol tasks are handled by a protocol accelerator that is integrated on-chip with a 32-bit general-purpose processor in order to achieve a moderate (20–40 MHz) system clock frequency. This enables low-power wireless devices compliant with this standard, providing high data rate, multimedia communication. One of the main tasks of the protocol accelerator is to analyze received or transmitted beacons. Based on the channel time allocations broadcast in the beacon and frame information stored in a hardware transmission queue, frames are transmitted without immediate control of the processor. Other features of the protocol accelerator include CRC generation, handling of immediate acknowledgment frames, and direct memory access. 相似文献
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This paper examines the overhead associated with the IEEE Std 802.15.3 medium access control (MAC) protocol when used in conjunction
with Ultra Wide-Band (UWB) radio technology. Particular features of the protocol examined include establishing, modifying
and terminating data streams. The main focus of the paper is to investigate the overhead introduced in terms of energy consumption
to manage the communication links. One of the main UWB technology candidates, Impulse-Radio (IR-UWB), utilizes very short
time domain pulses which are low power and difficult to detect. This raises the question of how to design an efficient MAC
protocol to harness the potential of the physical layer (PHY). For high data rate WPAN applications, the IEEE Std 802.15.3
protocol has been proposed as a suitable MAC. In the simulations the data source rate and the number of devices in the network
are varied and the considerable overhead produced by command frames is observed. 相似文献
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由于卫星通信传输时延大,因此误码造成丢帧后,增加的传输时间严重影响卫星通信。针对卫星通信普遍采用的卫星数字视频传输协议(DVB_S),通过比较分析自动重传(ARQ)、选择性重传(SR_ARQ)和主动性重传(CA_ARQ)3种重传机制的误码率与丢帧率的关系,给出了3种情况的理论延时性能,理论推导和仿真结果都表明CA_ARQ重传机制性能最为稳定,延时最小,更加适合卫星信道应用。 相似文献
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The media access control (MAC) performance of a large-scale wireless sensor network (L-WSN) determines the efficiency of the wireless communication channel. A good MAC protocol could reduce network energy consumption and network delay, which are two problems to be solved urgently in L-WSN. In this paper, we proposed a multi-level integrated MAC protocol (MI-MAC) to solve the overall performance optimization problem of L-WSN. Compared with other protocols, MI-MAC has two mainly improved performances: (1) It improved binary exponential backoff algorithm by twice back off strategy; (2) It designed a sending and receiving algorithm based on the threshold value to recognize control frames (small frames), which effectively avoids the collision probability of data frame. The simulation results show that the MI-MAC protocol improves network throughput and delay performance, significantly reduces energy consumption, and obtains overall network optimization. 相似文献
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文章从分析CAN 2.0B总线协议入手,通过计算CAN总线的总线负载率,得出单个CAN总线传输报文帧的上限值。针对单个CAN总线不能满足通信需求的问题,提出了将网络节点划分在两个子网中的优化方法,最后,介绍了将本方法应用于优化某模拟CAN总线节点的例子。 相似文献
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七位量子信道编码与纠错 总被引:1,自引:1,他引:0
在量子网络的两个站点间通信时,一旦数据帧中出现误码就需要重新发送数据帧,此举虽然能够保证数据的正确性,但是在一定程度上增加了信道的压力、降低了通信效率。为了缓解信道压力,从量子态的复制、隐形传送的过程出发,针对现有的量子纠错电路进行分析和改进,设计出了七粒子纠缠态的量子纠错线路,七粒子纠缠态量子纠错可以纠正不多于3位量子态出现的位反转或者位相翻转错误。并对改进前后协议的效率、信道的利用率进行对比,发现改进后的纠错电路能有效提高数据传输的效率,为以后多粒子纠错提供可参考的依据。 相似文献