刘月阳; 纪红; 乐光新
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0001-05
A wireless sensor network is typically composed of hundreds, even thousands of tiny sensors used to monitor physical phenomena. As data collected by the sensors are often redundant, data aggregation is important for conserving energy. In this paper, we present a new routing protocol with optimal data aggregation. This routing protocol has good performance due to its optimal selection of aggregation point locations. This paper details the optimal selection of aggregation point locations.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0006-04
This paper describes an onboard computer with dual processing modules. Each processing module is composed of 32 bit ARM reduced instruction set computer processor and other commercial-off-the-shelf devices. A set of fault handling mechanisms is implemented in the computer system, which enables the system to tolerate a single fault. The onboard software is organized around a set of processes that communicate among each other through a routing process. Meeting an extremely tight set of constraints that include mass, volume, power consumption and space environmental conditions, the fault-tolerant onboard computer has excellent data processing capability that can meet the erquirements of microsatellite missions. 16 Refs. In English.
赵锐 李焱 杨大成
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0010-05
It is well known that it is impossible for complex orthogonal space-time block codes with full diversity and full rate to have more than two transmit antennas while non-orthogonal designs will lose the simplicity of maximum likelihood decoding at receivers. In this paper, we propose a new quasi-orthogonal space-time block code . The code is quasi-orthogonal and can reduce the decoding complexity significantly by employing zero-forced and minimum mean squared error criteria. This paper also presents simulation results of two examples with three and four transmit antennas respectively.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0015-05
This paper proposes a novel energy-aware geographical forwarding protocol utilizing adaptive sleeping, in which each node selects its relay based on a new criterion that is based on its residual energy reserves and its geographical location to guarantee energy efficiency. In addition, this paper presents an adaptive sleep mechanism fully integrated into the new relay criterion, in which each node sleeps for a variable duration based on its residual energy reserves. Simulation results show that the proposed protocol significantly reduces the energy consumption of the network and improves its balance, especially when on heavy traffic load in dense networks. Our protocol is 20 times better in balancing the energy consumption compared with geographical random forwarding protocol. 14 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0020-05
This paper proposes a sectorized distributed antenna system for the orthogonal frequency division multiplexing system in order to both reduce the co-channel interference introduced by frequency reuse and maintain high spectral efficiency. The proposed system is composed of many 120-degree sectorized antennas that are uniformly distributed throughout the whole coverage area. Three adjacent sectors from different antennas share the same frequency band, which can be reused on the adjacent antennas. The new structure provides downlink interference divergence that greatly reduces co-channel interference and improves the system capacity, compared to the traditional cell structure with frequency reuse factor equal to 3. Multiple antennas broadcasting the same signal for a user using the same frequency, known as simulcasting, has been widely studied in distributed antenna systems. However,this paper demonstrates that simulcasting is not suitable for the close interfering structure. Multiple input multiple output distributed antenna systems might be a better choice. 18 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)-01-0025-04
The complex orthogonal designs with maximal rates and minimal delays is an open problem for space-time block codes. Maximal rates can effectively transmit symbols to the lonest distance in the space dimension ; and minimal delays is the least decoding delays in the time dimension. Many authors have observed that regarding the complex orthogonal designs for space-time block codes with the antennas n = 4k (k N), its minimal delay is the same as that for n=4k-1. However none was able to prove it.In this paper, we use the characteristics of Hadamard matrix to prove this property to fulfill this vacancy. 16 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0029-05
This paper presents an approach to build a flow of grid services named GFlow. This approach converts all of the services’ interfaces in globus toolkit 3 into platform independent model format. The conversion uses eclipse modeling framework plug-ins and graphical editing framework plug-ins to parse the models into platform specific models, which are responsible for implementation of grid services’ clients and servers and their automatic deployment. This paper emphasizes on design method, which uses model drive architecture, and design process, which uses model-view-control. 14 Refs. In English.
胡晓; 宋俊德; 宋梅; 周威
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0034-06
Hierarchical mobility management is sensitive to the failure of gateway mobility agents and prone todegrade performance on heavy loads. This paper proposes a distributed and adaptive location management scheme based on Hierarchical Mobile IPv6. This scheme can balance the loads of mobility anchor points and increase the robustness of the hierarchical structure to certain extents. In this scheme, the optimized IP paging scheme is adopted to reduce the paging signaling cost and improve the scalability of the hierarchical mobility management. We implement the distributed and adaptive location management scheme in a simulation platform and compare its performance with that of two other location management schemes. Our simulation results show that our scheme is capable of balancing the signaling and traffic loads of mobility anchor points, decreasing the average handover latency, and increasing the throughout of the visited networks. 16 Refs. In English.
宋江旺; 糜正锟; 成际镇
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0040-04
One of the limitations of current content delivery networks is lack of support for environment aware content delivery. This paper first discusses the requirements of such support, and proposes a new metadata gateway based environment aware content delivery architecture. The paper discusses in some details key functions and technologies of environment aware content delivery architecture, including its APIs and control policies. Finally the paper presents an application to illustrate advantages of environment aware content delivery architecture in the context of next generation network. 16 Refs. In English.
任勋益; 王汝传; 王海艳
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0044-05
This paper proposes a distributed denial-of-service attack detection method based on self similar and wavelet analysis. This method adopts an optimized transmission control protocol cookie technology for filter optimization in order to accurately detect and efficiently filter the traffic of distributed denial-of-service attack. This paper presents the design of our software, and describes all important algorithms of detection and filtering. Experimental results showed that our method has only a low delay to detect abnormal traffic of distributed denial-of-service attacks，and with a high percentage of filtering. 15 Refs. In English.
姜光兴; 朱洪波; 曹伟
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0049-04
This paper presents the design of a class of pulses that are based-on Hermite functions for ultra-wideband communication systems. The presented class of pulses can not only meet the power spectral emission constraints of federal communications commission , but also have a short duration for multiple accesses. This paper gives closed form expressions of auto- and cross-correlation functions of the proposed pulses, which can be used to evaluate the performance of the correlator receiver. Furthermore, the paper investigates, under various channel conditions, the spectrum characteristic and the bit error rate of the pulses’ waveforms. The investigation conditions include additive white Gaussian noise channels, multiple-access interference channels, and fading multipath channels. Our results indicates that our systematic algorithm is flexible for designing ultra-wideband pulses that conform to spectral emission constraints and offer good bit error rate performance. 17 Refs. In English.
顾雪琳; 田辉; 杨宁; 张平
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0053-07
Based on a discussion of the requirements for the multiple acess control protocol of beyond third-generation mobile systems, we in this paper articulate the needs of the new multiple acess control protocol with support of high-speed transmission and guaranteed quality of service, for voice, video and audio. In light of these, we present the design of a new multiple acess control protocol, called intelligent slot-subcarriered assignment multiple acess control protocol, to support multiple service categories and to yield high spectral efficiency. Our simulation results verify that intelligent slot-subcarriered assignment multiple acess control protocol can not only provide low delays for the real-time traffic by using bandwidth reservation and effectual scheduling, but also make full use of the limited bandwidth by using a dynamic sub-carrier assignment algorithm. 15 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0060-03
KASUMI is a block cipher that forms the heart of the 3GPP confidentiality algorithm f8, and the 3GPP integrity algorithm f9. This paper presents a hardware-based high-performance field programmable gate array implementation of the KASUMI algorithm. Our KASUMI implementation uses pipeline techniques and a field programmable gate array device, and outperforms previous published KASUMI implementations in terms both of clock frequency and of throughput. 10 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0063-04
This paper presents an unified comprehensive model for the analysis of the spectral properties of Fabry-Pérot laser diodes and conventional semiconductor optical amplifiers. We develop the model by considering the wide-band amplified spontaneous emission fields and the input optical signal fields in a general frame. Specifically, this paper discusses theoretical aspects of the model in details, which are based upon the spectra of material gain and spontaneous emission power, nonlinear gain suppression, and longitudinal spatial hole burning. This paper also presents simulation results of the model for the case of conventional semiconductor optical amplifier and the case of Fabry-Pérot laser diode to demonstrate its capabilities. 18 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0067-04
This paper presents a novel self-synchronization scheme utilizing a semiconductor optical amplifier and an optical band-pass filter. Implemented using cross gain modulation and self frequency shift, the proposed scheme has a simple structure that does not need any special marker pulses. With proper tuning of semiconductor optical amplifier and optical band-pass filter parameters and delay time of the control pulse, we, through simulation, obtain a synchronization clock with the intensity contrast ratio of more than 20 dB from RZ pseudorandom bit sequence at different operation speeds. 16 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0071-04
This paper discusses the design of a fully differential 2.1 GHz CMOS low noise amplifier using the TSMC 0.25 μm CMOS process. Intended for use in 3G, the low noisse amplifier is fully integrated and without off-chip components. The design uses an LC tank to replace a large inductor to achieve a smaller die area, and uses shielded pad capacitances to improve the noise performance. This paper also presents evaluation results of the design. 18 Refs. In English.
余华; 邹雪城; 陈朝阳
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0075-04
This paper presents a super performance bandgap voltage reference for DC-DC converter with adjustable output. It generates a wide range of voltage reference ranging from sub-1V to 1.221 7 V and has a low temperature coefficient of 2.3×10-5/K over the temperature variation using the current feedback and resistive subdivision. In addition, the power supply rejection ration of the proposed bandgap voltage reference is 78 dB. When supply voltage varies from 2.5 V to 6 V, output VREF is 1.221 685±0.055mV. 19 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0079-05
In certain cases, noises can improve signal transmission or signal processing. This phenomenon is the so-called stochastic resonance. In this paper, we firstly present two theorems to prove that the noisy threshold neuron shows SR in terms of the probability of correct reception. Secondly, we analytically discuss stochastic resonance effects and give the probability-optimal noise levels for four representative noises. Finally, we discuss the stochastic gradient ascent learning law, which can be used to find the probability-optimal noise levels. We also present our simulation results for the four representative noises. These results indicate that stochastic resonance is favorable both in biological neurons and in signal processing. 22 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0084-04
This paper proposes a new inter-cell interference cancellation algorithm called subspace projection in order to eliminate the stronger inter-cell interference . This algorithm is designed for the reverse link of time division duplex-code division multiple access systems. The algorithm works by projecting desired users’ signal vector onto the subspace orthogonal to the subspace that interfers the users’ signal. Low-level simulation results show that the scheme eliminates the inter-cell interference efficiently, improves the receiver performance, and increases the system capacity. 9 Refs. In English.
张永忠; 赵银亮; 李增智
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0088-05
In this paper, we discuss quality of service requirements and impacts of different workloads of each service class on the resource proportion allocation scheme, and formulize the problem of minimizing the quality of service miss rate of service requests by using the queuing theory. The optimally allocating resource proportion scheme is obtained by the Lagrangian optimization approach. Our simulation results show that our scheme is efficient. 20 Refs. In English
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0093-06
This paper derives a low-complexity turbo equalization algorithm for turbo coded multiple input multiple output / orthogonal frequency division systems. This algorithm consists of soft-output decision-feedback equalization with a probabilistic data association algorithm and a soft-input soft-output turbo channel decoder using iterative operations. In each iteration, extrinsic information extracted from the probabilistic data association algorithm detector and from the channel decoder is used as the prior information for the next iteration to realize iterative channel equalization and channel decoding. Our simulation results show that the algorithm improves the signal noise ratio around 1dB with bit error rate reaching 10-6 when the Eb/No=4 dB compared to minimum mean square error and match filter, and can greatly reduce the intersymbol interference at a low overall complexity of O(N3) after 2 iterations. 20 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0099-05
Extend case transfer architecture inter-organization workflow management fits the needs of collaboration commerce. However, during the third step of Extend case transfer architecture, modifications of private workflows might cause some fatal problems, such as dead locks, live locks and dead tasks. These problems could change the soundness and efficiency of overall workflow. This paper presents a Petri net based approach to protect the inheritance of public workflows in private domains, and discusses an implementation of our collaboration commerce workflow model. 19 Refs. In English.
王治宇; 邱燕琳; 桂世河
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0104-05
This paper reviews the development of quality management and competitive advantage, and explores the notion of strategic status of quality as a source of sustained competitive advantage. In addition, the paper presents a number of suggestions to the Chinese telecommunications industry on the development of quality competence in order to sustain an advantage over foreign competitors. 17 Refs. In English.
中国邮电高校学报(英文版), 2006, 13 (1). doi： 1005-8885(2006)01-0109-05
This paper discusses the design of a customer satisfaction measurement index system of express mail service. It presents objectives and principles of the design based on hierarchical structures. We have devised a diagram for modeling customer satisfaction, and a detailed analysis of customer satisfaction is conducted. This paper presents our customer satisfaction model and analysis results. 15 Refs. In English.