一种使用偏转路上的多信道ATM交换网络

支持多信道传输的多信道交换技术是网络资源有效利用的方法之一。本文提出了一种偏转路由的多信道ＡＴＭ交换网络，可以解决输出的信道群中的信道竞争问题，说明了它的结构和原理，并阐述了多信道带宽分配问题，最后给出在一种突发业务流量模型上的性能分析。     

一种多信道ATM交换机的实现

本文研究了一种多信道ATM交换网络,使用一种多路径交换结构网络作为多信道交换的路由网络代替Banyan网络。给出了信道分配网络的设计原理。阐明了多信道ATM交换的带宽分配方案,重点说明了传输阶段的带宽分配方法。     

多信道ATM交换和多信道传输技术

ATM技术以其统计复用的最大特点正在被广泛采用。支持多信道传输的多信道交换技术是网络资源有效利用的方法之一。本文论述多信道ATM交换和多信道传输技术的原理,说明了多信道带宽分配方案和多信道交换技术要解决的关键问题,以及多信道交换网络设计中存在的一些问题。     

一种多信道ATM交换机的实现

本文研究了一种多信道ＡＴＭ交换网络,使用一种多路径交换结构网络作为多信道交换的路由网络代替Ｂａｎｙａｎ网络,给出了信道分配网络的设计原理,阐明是了多信道ＡＴＭ交换的带宽分配方案,重点说明了传输阶段的带宽分配方法。     

一种用于多信道ATM交换的路由网络

主要提出了一种多信道交换的路由网络,叙述了多信道交换路由网络的工作原理,阐明了信元序列问题的处理方法。     

Ad Hoc网络支持QoS保障的多信道MAC协议

提出一种基于多信道的QoS保障方案,结合业务区分和资源预留两种QoS保障策略,保证优先级高的业务及时接入信道;并且建立节点发送链表,给数据通信预留一段时间,实现数据信道上连续的帧交换,有效地使用了数据信道资源。     

Ad Hoc网络支持QoS保障的多信道MAC协议

提出一种基于多信道的Qo S保障方案,结合业务区分和资源预留两种Qo S保障策略,保证优先级高的业务及时接入信道;并且建立节点发送链表,给数据通信预留一段时间,实现数据信道上连续的帧交换,有效地使用了数据信道资源。     

无线通信的交换网络设计

本文着重介绍了利用ＭＣＳ－５１系列单片微机技术，实现对模拟开关阵列集成电路的控制构成交换矩阵网络，完成多条有线电话与多个无线信道之间的自动接续，完成多个无线信道与多个无线信道之间的自动接续。     

一种宽带多输入多输出双向信道的频域辨识方法

提出一种基于空间交换最大期望(SAGE)算法的信道频域辨识方法。该方法能够有效地估计收发联合宽带多输入多输出(MIMO)双向信道的三维离开角、到达角、极化等特征参数。仿真的结果表明:该方法能准确地估计MIMO双向信道的参数,适合MIMO信道建模的需求。     

基于空分复用的多信道机间紫外光通信定向MAC协议

为了弥补飞行编队任务分配情况和不同模式下紫外光定向通信存在耳聋问题的缺陷,采用一种基于空分复用的多信道机间紫外光通信定向信道接入协议,建立了机间紫外光通信网络模型。通过在紫外节点安装多个不同方向的紫外收发装置来实现多信道信息交换,并仿真验证了多信道通信使耳聋问题得到明显缓解,提高了网络吞吐量,降低了网络时延,使得网络性能显著改善。结果表明,多信道通信与单信道通信相比,网络吞吐量增加,平均时延减小,网络性能大幅度提高,并且采用三信道通信模式通信效果最佳。     

A nonblocking architecture for broadband multichannel switching

The paper investigates multichannel switching as a promising alternative to traditional single-channel switching where virtual paths established in a switch are between a single input channel and a single output channel. A particular non-blocking condition is derived for flip networks, which is exploited to realize a multichannel switching architecture that supports an arbitrary number of channel groups. The architecture is internally nonblocking and bufferless. Using one flip network recursively a number of times based on the number of channel groups, the resulting architecture becomes efficient in the sense that the cross point complexity is O(N log₂ N) for N inputs. Other distinguishing features are the abilities to provide multicasting, superrate switching (i.e., rates that exceed the capacity of a single channel are accommodated), multirate switching (i.e., bit pipes of different rates are supported simultaneously), multiple performance requirements (i.e., services with different performance requirements are treated accordingly), and fair access to all inputs (i.e., no input is systematically discriminated against). In multichannel switching, cells belonging to a single session can traverse multiple channels. Providing the cell sequencing integrity becomes a challenging issue. The architecture proposed in the paper accomplishes the task without employing any cell resequencing mechanism     

A Multirate Switching Network for Broadband Channels

A broadband ISDN switching network model is presented, switching the channel types H2, H3, and H4 envisaged by the CCITT. The synchronous time division multiplex technique is applied. The switching network operates at the basic bit rate of the H2-channel; H3and H4-connections are established via multichannel connections of up to four basic channels. H2-connections which are part of one H3- or H4-connection always have to use common interconnection links. This is a favorable solution to keep digit sequence integrity for multichannel connections, but influences blocking characteristics of the switching network. The implementation of an optimal path selection method plays a fundamental role. In such a multichannel switching network, blocking probabilities for H2-, H3-, and H4-connections must be distinguished. They do not only depend on the total offered load, but also on the proportions of H2-, H3-, and H4-connections (traffic mix). The simulation results presented in this paper prove that multirate switching via multichannel connections is feasible for the broadband channel types H2, H3, and H4, and that the proposed switching network has a sufficiently high traffic capacity whatever the traffic mix may be.     

存在严重通道误差情况下的SAR-GMTI方法分析

天线方向图不一致和天线相位中心间距误差等通道幅相误差会使传统多通道地面运动目标检测方法的杂波抑制性能下降,从而最终影响地面运动目标的检测性能.分析了空时自适应处理技术和相位中心偏置天线技术2种方法在较大通道误差情况下的性能,并介绍了一种二维自适应的通道误差校正方法.该误差校正方法是一种运算量小且性能较好的误差估计与补偿方法.通过实测数据验证了分析的正确性和方法的有效性.     

Capacity of Multichannel Wireless Networks Under the Protocol Model

This paper studies the capacity of a n node static wireless network with c channels and m radio interfaces per node under the protocol model of interference. In their seminal work, Gupta and Kumar have determined the capacity of a single channel network (c=1, m=1). Their results are also applicable to multichannel networks provided each node has one interface per channel (m=c) . However, in practice, it is often infeasible to equip each node with one interface per channel. Motivated by this observation, we establish the capacity of general multichannel networks (m les c). Equipping each node with fewer interfaces than channels in general reduces network capacity. However, we show that one important exception is a random network with up to O(logn) channels, where there is no capacity degradation even if each node has only one interface. Our initial analysis assumes that the interfaces are capable of switching channels instantaneously, but we later extend our analysis to account for interface switching delays seen in practice. Furthermore, some multichannel protocols proposed so far rarely require interfaces to switch, and therefore, we briefly study the capacity with fixed interfaces as well.     

MOSAIC: a multiwavelength optical subcarrier multiplexed controllednetwork

The experimental demonstration of MOSAIC, a reconfigurable WDM add/drop network with subcarrier multiplexed control, is presented. The MOSAIC network implements the optical layer protocol to support bit-rate transparent multichannel lightpaths. Two types of add/drop multiplexers are implemented and combined in a three-node experiment. Multihop lightpaths are established giving an end-to-end bit error rate of better than 10^-9 at 1.2 Gbps. The reconfigurable add/drop multiplexer is based on a novel dilated 2×2 acoustooptic filter switch crossconnect and an analog optoelectronic crossconnect that drives a ten-wavelength laser array transmitter up to 2.5 Gbps per wavelength. The fixed wavelength add/drop multiplexer utilizes a fast digitally tunable laser transmitter. Both add/drop multiplexers support bit-rate transparent 2R optoelectronic regeneration as well as wavelength translation. Subcarrier multiplexing on each wavelength is used to support channel state monitoring and channel equalization as well as transmission of digital network control information. Systems experiments demonstrate cascaded 2R optoelectronic regeneration with wavelength translation and cascaded multichannel optical switching with up to seven hops. It is shown that combining cascaded 2R optoelectronic regeneration with cascaded multichannel optical switching can be used to balance jitter accumulation and amplified spontaneous emission generated amplitude noise to yield high signal-to-noise ratio for lightpaths     

An Efficient Representation Method for ICLD with Robustness to Spectral Distortion

The inter‐channel level difference (ICLD) is a cue parameter to estimate spectral information in binaural cue coding that has been recently in the spotlight as a multichannel audio signal compression technique. Even though the ICLD is an essential parameter, it is generally distorted by quantization. In this paper, a new modified ICLD representation method to minimize the quantization distortion is proposed by adopting a flexible determination of the reference channel and the unidirectional quantization scheme. Our experimental result confirms that the proposed method improves the multichannel audio output quality even with the reduced bit‐rate.     

一种信噪比指导信道均衡方式切换的算法

针对短波信道数据引导均衡算法(Data-Directed Equalization Algorithm,DDEA)及其判决反馈式DDEA(Decision Feed-back Equalizer DDEA,DFE-DDEA)算法在高低信噪比上误码性能互补的特点,在分析最大似然信噪比估计算法基础上,提出了采用实时信噪比估计以指导信道均衡方式、在DDEA与DFE-DDEA间动态切换的DS-DDEA(DynamicSwitching DDEA)算法,改善误码率整体性能。仿真算法验证了信噪比估计和DS-DDEA算法的可行性和有效性。     

MCAS:车载网络中带负载均衡的多信道接入机制

近几年车载自组织网络在学术界和工业界都发生了巨大的变化。车载网络运用多信道操作模式来提供开放的安全服务和安全有效的驾驶体验,由此可见多信道接入在车载网络中占据非常重要的角色。吞吐量和时延是两个很重要的指标。基于最新标准,提出了基于信道通信间负载均衡和车辆间信道协作的多信道接入机制MCAS。理论分析和仿真结果都表明,MCAS在吞吐量和服务传输时延上都优于WAVE。     

Channel switching between receivers of FDM coherent optical star network

The authors present channel switching results obtained between receivers of an FDM optical coherent fibre star network. The system consists of six optical channels FSK-modulated at 200 Mbit/s and spaced by 2.2 GHz. The channels are multiplexed by a 16*16 optical star coupler. Two of the multichannel signals exiting this device are demultiplexed by their respective random access digitally tuned heterodyne receivers. Simultaneous switching between pairs of channels is obtained by command of a personal computer controlling both receivers.<>