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为了抑制脉冲噪声对电力线正交频分复用(OFDM)通信系统的影响,最常用的方法之一是在接收端OFDM解调器之前前置一个置零非线性单元,即传统置零法。然而,由于引入了非线性失真,其性能并不理想。针对传统置零法引起的非线性失真问题,提出了一种基于迭代消除非线性失真的改进置零法。首先,对接收到的时域OFDM信号进行脉冲噪声检测和置零处理;然后,在频域利用已检测的符号来重构时域置零处理引入的非线性失真,并通过迭代提高重构的准确性;最后,从频域接收信号中减去重构的非线性失真。仿真结果表明,所提改进算法与传统置零法相比,有非常大的性能提升,增强了电力线OFDM通信系统对脉冲噪声的抵抗能力。 相似文献
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Lampe L. Schober R. Simon Yiu 《Selected Areas in Communications, IEEE Journal on》2006,24(7):1389-1400
In this paper, we consider transmission in relatively wide-stretched power line communication (PLC) networks, where repeaters are required to bridge the source-to-destination distance. In particular, it is assumed that each network node is a potential repeater and that multihop transmission is accomplished in an ad hoc fashion without the need for complex routing protocols. In such a scenario, due to the broadcasting nature of the power line channel, multiple repeater nodes may receive and retransmit the source message simultaneously. It is shown that, if no further signal processing is applied at the transmitter, simultaneous retransmission often deteriorates performance compared with single-node retransmission. We therefore advocate the application of distributed space-time block codes (DSTBCs) to the problem at hand. More specifically, we propose that each network node is assigned a unique signature sequence, which allows efficient combining at the receiver. Most notably, DSTBC-based retransmission does not require explicit collaboration among network nodes for multihop transmission and detection complexity is not increased compared with single-node retransmission. Numerical results for multihop transmission over PLC networks show that DSTBC-based retransmission achieves a considerably improved performance in terms of required transmit power and multihop delay compared with alternative retransmission strategies. 相似文献
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Intrabuilding power lines provide a readily available and easily accessed network for personal computer (PC) communications within buildings. The use and performance of carrier-sense multiple access with priority acknowledgements (CSMA/PA) on such networks is described. The communication characteristics of intrabuilding power-line channels are summarized and found to suffer from highly variable and unpredictable signal-to-noise ratios and bit-error rates. The advantages of CSMA/PA relative to polling and token-passing access protocols are discussed. The architecture of a CSMA/PA implementation is described. The choice of the best data-link packet length is determined from throughput measurements to be approximately 1000 bits. Delay-throughput performance is measured at 1.2, 2.4, 4.8, and 9.6 kb/s using a phase-shift-keyed (PSK) spread-spectrum modem. Results are included for the potentially difficult problem of transmission across power phases. A discussion of results obtained and their implications for PC intrabuilding communications is also included 相似文献
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Katayama M. Yamazato T. Okada H. 《Selected Areas in Communications, IEEE Journal on》2006,24(7):1267-1276
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Kohno R. Imai H. Hatori M. Pasupathy S. 《Selected Areas in Communications, IEEE Journal on》1990,8(4):691-699
The authors propose and investigate an adaptive canceller of intersymbol and cochannel interference due to channel distortion and cross-correlation among pseudonoise sequences assigned to individual users of a DS-SSMA (direct-sequence spread-spectrum multiple-access) system. In order to implement a local area network (LAN) by using a power line installed in a building wall as a transmission channel, the authors have investigated utilization of DS-SSMA which has advantages such as robustness against narrow-band interference and noise and realization of asynchronous code division multiple access. In a power line, however, restriction of transmission bandwidth for communications makes it difficult to suppress cochannel interference and the channel is also time-varying due to fluctuation of loads. Since the proposed canceller adaptively eliminates cochannel interference as well as intersymbol interference, it can facilitate synchronization and increase the number of the simultaneously accessing users on a power line with restricted processing gain. The error probability in the output of the canceller is theoretically calculated for the steady-state case by using a Markov model. Computer simulations illustrate stable convergence properties of the canceller 相似文献
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According to the problem that the threshold for traditional blanking depends on the characteristic parameters of noise and exist large deviation,an adaptive noise mitigation algorithm based on peak estimate and feedback compensation(ANMPEFC)in power line communication was proposed.First,SLM mapping preprocessing method was employed to reduce the PAPR of emission signal,peak information was used to estimate the frequency of the received signal and the relationship between peak frequency and impulse characteristics was established.Next,received signal was processed by blanking block and feedback compensation block adaptively according to estimated pulse frequency.Finally, performance of proposed algorithm and existing algorithms were analyzed based on threshold deviation.According to the results from simulation,it is clearly demonstrated that the proposed ANMPEFC can work in power line impulse noise environment without knowing the noise characteristics and has better performance in contrast to existing impulse noise suppression algorithm. 相似文献
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For fixed quality-of-service constraints and varying channel interference, how should a mobile node in a wireless network adjust its transmitter power so that energy consumption is minimized? Several transmission schemes are considered, and optimal solutions are obtained for channels with stationary, extraneous interference. A simple dynamic power management algorithm based on these solutions is developed. The algorithm is tested by a series of simulations, including the extraneous-interference case and the more general case where multiple, mutually interfering transmitters operate in a therefore highly responsive interference environment. Power management is compared with conventional power control for models based on FDMA/TDMA and CDMA cellular networks. Results show improved network capacity and stability in addition to substantially improved battery life at the mobile terminals. 相似文献
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An interconnected type-1 fuzzy algorithm for impulsive noise cancellation in multicarrier-based power line communication systems 总被引:1,自引:0,他引:1
Ribeiro M.V. Duque C.A. Romano J.M.T. 《Selected Areas in Communications, IEEE Journal on》2006,24(7):1364-1376
This paper introduces an interconnected type-1 fuzzy algorithm which is trained by a modified version of the Scaled Conjugated Gradient method for impulsive noise cancellation in discrete multitone/orthogonal frequency-division multiplexing (DMT/OFDM)-based systems for broadband power line communications. The advanced algorithm makes use of the fuzzy systems capacity of dealing with uncertainties to reduce the presence of high-power impulsive noises while the DMT/OFDM technique copes with the severe intersymbol interference observed in power line channels. As a result, for a given error probability, a high number of bits can be allotted to each subchannel due to the signal-to-noise ratio enhancements achieved by the proposed fuzzy algorithm. The simulation results show that the novel fuzzy algorithm not only achieve a high data rate, but it also outperforms the standard impulsive noises techniques and other computational intelligence-based techniques, especially in the presence of additive and high-power impulsive noises. 相似文献
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基于ASON的电力通信网演进策略 总被引:2,自引:0,他引:2
文章简要介绍了自动交换光网络(ASON)设备的应用现状、电力光传输网的网络结构、建设方式、业务类型和流向及存在的问题,指出了ASON适用于骨干/城域网的特点,并从网络规划设计、演进方式、ASON与传统光网络的互通和演进过程中需要注意的问题等方面简要阐述了电力通信网基于ASON技术的演进策略. 相似文献
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电力线通信为配电自动化业务的开展提供了廉价的数据通信平台,但由于配电网具有网络拓扑未知和信道时变的特点,会导致可靠性降低和通信距离存在不足,这些问题很难在物理层进行解决,需要通过上层的通信协议来解决。为此提出一种自适应的路由算法,通过此算法可以形成节点之间的正常路由功能和链路修复功能,以增大电力线载波通信的通信距离,并提高其可靠性。仿真结果表明,该算法能够快速有效地找到网络协调节点到目的节点的路由。 相似文献
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Chang‐Keun Park Joon‐Myung Kang Mi‐Jung Choi James Won‐Ki Hong Yong‐Hun Lim Seongho Ju Moon‐Suk Choi 《International Journal of Network Management》2010,20(1):35-55
Power line communication (PLC) is an evolving technology which uses existing power lines for data transmission. Like any other communication network, PLC networks need to be managed to ensure efficient use of resources and secure operations. Currently, major PLC chip vendors are trying to provide network management solutions based on the Simple Network Management Protocol (SNMP) by developing their own management systems, but they cannot manage heterogeneous PLC networks comprised of PLC devices from various PLC chip vendors. In this paper, we provide our experience of developing and testing an integrated management system for a heterogeneous PLC network based on SNMP. We present our approach for integrated management by defining the common PLC management information base (MIB) and an integrated PLC proxy agent for providing interoperability to legacy PLC devices which do not support the common PLC MIB. We also present the development of an integrated PLC network management system and its test in heterogeneous PLC networks deployed in South Korea. The contribution of our work is to provide a guideline for developing and testing integrated NMSs for any heterogeneous networks including PLC networks. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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A hybrid relay control mechanism for ribbon topology in low‐voltage power line communication networks 下载免费PDF全文
The communication reliability and distance of the low‐voltage power line communication system are seriously affected by the channel interference and the time variant load impedance. Therefore, how to control the relay nodes to reduce the communication delay and improve the communication reliability is mainly considered in the design. A novel hybrid relay control mechanism (HRCM) that includes the static relay pre‐configuration and the dynamic relay selection is designed for the ribbon topology in the low‐voltage power line communication networks. In the ribbon topology, the initial configuration for the communication link is realized through the pre‐configure relay nodes, which guarantees that the concentrator can communicate with the furthest terminal node. During the normal operations, the dynamic relay node is selected according to the sequence number of the uplink or downlink data frame and the data discard strategy. With the relay node dynamical selected mechanism, the frame repeated transmission can be avoided and the communication delay is reduced. The actual test results show that the hybrid relay control mechanism can effectively extend the communication distance, improve the communication real‐time and the reliability of the low‐voltage power line communication. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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