KIMBA DIT ADAMOU Boubacar, ZOU Shi-hong, ABDOU Saley, MA Yi-hui, CHENG Shi-duan
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60169-7
摘要 ( 2158 ) PDF (263 KB)( 403 )
This article describes a new model of a cooperative file sharing system in a wireless Mesh network. The authors’ approach is to develop an efficient and cooperative file sharing mechanism based on opportunistic random linear Network Coding. Within this mechanism, every node transmits random linear combination of its packets according to cooperative priority, which is computed in a distributed manner according to the node-possible contribution to its neighbor nodes. With this mechanism, the more a node contributes to others, the more the node has chances to recover the entire file first. The performance metrics of interest here are: the delay until all the packets in a file have been delivered to all nodes, and an ideal packet size, by the use of which the authors can get the minimum transmission delay. Through extensive simulation the authors compare their mechanism with the current transmission process in a wireless Mesh network without random linear Network Coding. The authors found that using their mechanism, the nodes can cooperatively share the entire file with less transmission time and delay than the current transmission process without random linear network.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60170-3
摘要 ( 2333 ) PDF (198 KB)( 464 )
Target tracking is one of the most important applications of wireless sensor networks. Optimized computation and energy dissipation are critical requirements to save the limited resource of sensor nodes. A new robust and energy-efficient collaborative target tracking framework is proposed in this article. After a target is detected, only one active cluster is responsible for the tracking task at each time step. The tracking algorithm is distributed by passing the sensing and computation operations from one cluster to another. An event-driven cluster reforming scheme is also proposed for balancing energy consumption among nodes. Observations from three cluster members are chosen and a new class of particle filter termed cost-reference particle filter (CRPF) is introduced to estimate the target motion at the cluster head. This CRPF method is quite robust for wireless sensor network tracking applications because it drops the strong assumptions of knowing the probability distributions of the system process and observation noises. In simulation experiments, the performance of the proposed collaborative target tracking algorithm is evaluated by the metrics of tracking precision and network energy consumption.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60171-5
摘要 ( 3013 ) PDF (215 KB)( 412 )
Routing is one of the most important supporting parts in wireless sensor networks (WSNs) application that directly affects the application efficiency. Routing time and energy consumption are two major factors used to evaluate WSNs routing. This article proposes a minimum routing time and energy consumption (MiniTE) routing, which can ensure feasibility of the routing protocol both in routing time and energy consumption. Based on the MiniTE, WSNs can be partitioned into different regions according to the received signal strength indication (RSSI). Messages are sent by nodes in the region to their parent node and again up to their parent node until finally to the sink node. Theoretic evaluation and simulation results are given to verify the features of the protocol.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60172-7
摘要 ( 2940 ) PDF (240 KB)( 442 )
There are correlations of data in adjacent sensor nodes in wireless sensor networks (WSNs). Distributed source coding (DSC) is an idea to improve the energy efficiency in WSNs by compressing the sensor data with correlations to others. When utilizing the DSC, the network architecture that, deciding which nodes to transmit the side information and which nodes to compress according to the correlations, influences the compression efficiency significantly. Comparing with former schemes that have no adaptations, a dynamic clustering scheme is presented in this article, with which the network is partitioned to clusters adaptive to the topology and the degree of correlations. The simulation indicates that the proposed scheme has higher efficiency than static clustering schemes.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60173-9
摘要 ( 2165 ) PDF (216 KB)( 408 )
The non-uniform transmission and network topological structure are combined to investigate the spreading behavior of susceptible-infected-susceptible (SIS) epidemic model. Based on the mean-field theory, the analytical and numerical results indicate that the epidemic threshold is correlated with the topology of underlying networks, as well as the disease transmission mechanism. These discoveries can greatly help us to further understand the virus propagation on communication networks.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60174-0
摘要 ( 2978 ) PDF (259 KB)( 423 )
Waveforms play a key role in overlapping time division multiplexing (OvTDM) system. The OvTDM has been proved to be a novel transmission technique that can utilize time diversity to improve the bit error ratio (BER) performance in Rayleigh channel. According to the resulted law, the BER performance of Gaussian waveform in OvTDM also improves with the increase in the waveform parameter monotonically, and the rectangular waveform is the worst case of Gaussian waveform. In contrast, the spectrum effectiveness of Gaussian waveform OvTDM decreases with the increase in the waveform parameter. In the study, it is obtained that waveforms can achieve the best performance when the smallest correlation coefficient between neighbor symbols is .
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60175-2
摘要 ( 2358 ) PDF (277 KB)( 481 )
Resource allocation problem in multiuser multiple input single output-orthogonal frequency division multiple access (MISO-OFDMA) systems with downlink beamforming for frequency selective fading channels is studied. The article aims at maximizing system throughput with the constraints of total power and bit error rate (BER) while supporting fairness among users. The downlink proportional fairness (PF) scheduling problem is reformulated as a maximization of the sum of logarithmic user data rate. From necessary conditions on optimality obtained analytically by Karush-Kuhn-Tucker (KKT) condition, an efficient user selection and resource allocation algorithm is proposed. The computer simulations reveal that the proposed algorithm achieves tradeoff between system throughput and fairness among users.
赵爽,尧文彬,杨鸿文, WANG Ya-feng
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60176-4
摘要 ( 2633 ) PDF (188 KB)( 394 )
Switch-and-examine combining (SEC) is an interesting diversity technique that is simpler than selection combining (SC), whereas its performances is similar in terms of bit error rate (BER) and diversity order. As ergodic capacity is also a key performance index in modern wireless systems, this article analyzes the ergodic capacity of the SEC system. The numerical results show that the ergodic capacity of SEC with optimal threshold is similar to that of SC for arbitrary number of diversity branches.
李学华,CAO Yi-qing, 李振松,杨大成
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60177-6
摘要 ( 2220 ) PDF (227 KB)( 444 )
This article studies the degree distribution property of low density parity check (LDPC) codes by Gaussian approximation (GA) and presents an efficient hybrid automatic repeat quest (HARQ) scheme for LDPC-coded orthogonal frequency division multiplexing (OFDM) system. In the scheme, the important bits with large degrees have high retransmission priorities and are mapped to the sub-carriers with better channel quality indicator (CQI) levels in the OFDM system. The new scheme provides more protection to the bits with large degrees and thus contributes more to the decoding process by offering more transmission power. In this way the system performance would be improved. The statistics and simulation results also prove the new scheme.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60178-8
摘要 ( 2225 ) PDF (267 KB)( 391 )
In future wireless network, one user will require multiple homogeneous or heterogeneous services simultaneously. Then, the scheduling algorithm is not only responsible for assigning a resource block to different users but also sharing the assigned resource block among multiple services for one user. Most of the traditional scheduling algorithms are designed to serve one service per user, and cannot be applied directly to this scenario because of the fairness criterion. This article focuses on adaptive resource allocation for multiple services per user at the downlink of orthogonal frequency division multiplexing (OFDM) based system. This article addresses this integrative resource scheduling problem based on utility function. First, the optimal algorithm for dynamic subcarrier allocation and share is deduced for homogeneous best-effort service system. Then the algorithm is extended to heterogeneous services system by classifying the delay sensitive service according to the head-of-line packet delay. The design goal is to maximize aggregate utility function to exploit multiuser diversity gain to the greatest extent even as guaranteeing quality of service (QoS) for delay sensitive service.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60179-X
摘要 ( 2089 ) PDF (283 KB)( 452 )
The chaotic ant swarm algorithm (CAS) is an optimization algorithm based on swarm intelligence theory, and it is inspired by the chaotic and self-organizing behavior of the ants in nature. Based on the analysis of the properties of the CAS, this article proposes a variation on the CAS called the modified chaotic ant swarm (MCAS), which employs two novel strategies to significantly improve the performance of the original algorithm. This is achieved by restricting the variables to search ranges and making the global best ant to learn from different ants’ best information in the end. The simulation of the MCAS on five benchmark functions shows that the MCAS improves the precision of the solution.
明洋,SHEN Xiao-qin, WANG Yu-min
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60180-6
摘要 ( 2901 ) PDF (141 KB)( 437 )
In this article, based on Chatterjee-Sarkar’ hierarchical identity-based encryption (HIBE), a novel identity-based encryption with wildcards (WIBE) scheme is proposed and is proven secure in the standard model (without random oracle). The proposed scheme is proven to be secure assuming that the decisional Bilinear Diffie-Hellman (DBDH) problem is hard. Compared with the Wa-WIBE scheme that is secure in the standard model, our scheme has shorter common parameters and ciphertext length.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60181-8
摘要 ( 2177 ) PDF (141 KB)( 477 )
Three broadcast schemes for small receiver set using the property of RSA modulus are presented. They can solve the problem of data redundancy when the size of receiver set is small. In the proposed schemes, the center uses one key to encrypt the message and can revoke authorization conveniently. Every authorized user only needs to store one decryption key of a constant size. Among these three schemes, the first one has indistinguishability against adaptive chosen ciphertext attack (IND-CCA2) secure, and any collusion of authorized users cannot produce a new decryption key but the sizes of encryption modulus and ciphertext are linear in the number of receivers. In the second scheme, the size of ciphertext is half of the first one and any two authorized users can produce a new decryption key, but the center can identify them using the traitor tracing algorithm. The third one is the most efficient but the center cannot identify the traitors exactly.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60182-X
摘要 ( 2070 ) PDF (190 KB)( 486 )
The research on the identification scheme is an important and active area in computer and communication security. A series of identification schemes were proposed to improve the efficiency and security of the protocols by various methods. Based on the hardness assumption of the discrete logarithm problem in a gap Diffie-Hellman group and the difficulty of the collusion attack algorithm with k traitors, an efficient identification scheme is presented. Without random oracle models, the proposed scheme is then proved secure against impersonation and reset attacks in both concurrent and reset attack setting. Since the proposed scheme is simple, memory-saving, computation-efficient, and perfectly-secure, it is well suitable for use in smart cards.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60183-1
摘要 ( 2353 ) PDF (177 KB)( 392 )
The timing and Hamming weight attacks on the data encryption standard (DES) cryptosystem for minimal cost encryption scheme is presented in this article. In the attack, timing information on encryption processing is used to select and collect effective plaintexts for attack. Then the collected plaintexts are utilized to infer the expanded key differences of the secret key, from which most bits of the expanded secret key are recovered. The remaining bits of the expanded secret key are deduced by the correlations between Hamming weight values of the input of the S-boxes in the first-round. Finally, from the linear relation of the encryption time and the secret key’s Hamming weight, the entire 56 bits of the secret key are thoroughly recovered.
Using the attack, the minimal cost encryption scheme can be broken with known plaintexts and about calculations at a success rate . The attack has lower computing complexity, and the method is more effective than other previous methods.
贾华宇,CHEN Gui-can, ZHANG Hong
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60184-3
摘要 ( 2117 ) PDF (343 KB)( 406 )
The article presents a new (1+1)-bit/stage structure for pipelined analog-to-digital converters (ADC). When the input analog signal of the structure exceeds the converting range of the whole ADC, the signal can still be converted precisely and the output residue voltage of the structure will be in the converting range of the ADC. The structure is used in a 12-bit 40 MS/s pipelined ADC to test its function. The testing results show that the structure has right function and can correct the transition error induced by offset of comparators’ decision levels. The ADC implemented in Semiconductor Manufactory International Corporation (SMIC) 0.18 μm CMOS process consumes 210 mW and occupies a chip area of 3.2×3.7 mm2.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60185-5
摘要 ( 2982 ) PDF (281 KB)( 510 )
In this article, a design for the adaptive deblocking filter is proposed. To understand the real-time performance, a FILTER unit that can process eight pixels beside an edge simultaneously is applied in this design to increase filtering efficiency, and local memory is used to store all temporary data generated by the FILTER to reduce access to system bus. The filter makes every 4×4 sample block pipelined through the process units and achieves an efficiency of 80% for both the FILTER unit and the bus access unit. It can fulfill filtering process for a crystallographic information file (CIF, 352×288) format picture in 95 k clock cycles. The proposed design is part of a H.264/AVC decoder system-on-chip (SOC), which is fabricated in 0.18 μm complementary metal oxide semiconductor (CMOS) process. The filter module consists of 60 k gates and 25.7 kb static random access memory (SRAM) and it can filter a macro-block in 240 clock cycles.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60186-7
摘要 ( 2140 ) PDF (346 KB)( 482 )
A high performance white light emitter diode (LED) driver based on boost converter with novel single-wire serial-pulse digital dimming (SWSP) is proposed. The driver uses external serial programmed pulses and internal clock to simplify brightness control. By embedding a 5-bit digital analog converter (DAC) into the driver, wide dimming range is achieved. Moreover, a new dynamic slope compensation circuit is presented and other key circuits of the driver are optimized to get higher efficiency and fast transition response. A practical circuit is implemented with 0.6 um bipolar complementary-metal-oxide-semiconductor double-diffused-metal-oxide-semiconductor (BCD) technology. The simulation results show that the driver can provide both wide output current from 1.3 mA to 42 mA with 32-level digital dimming and higher efficiency up to 83% while it works at 1 MHz switching frequency with the input voltage variation from 2.7 V to 5.5 V.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60187-9
摘要 ( 2058 ) PDF (355 KB)( 370 )
Many ant colony routing (ACR) algorithms have been presented in recent years, but few have studied the problem that ants will get stuck with probability in any terminal host when they are searching paths to route packets around a network. The problem has to be faced when designing and implementing the ACR algorithm. This article analyzes in detail the differences between the ACR and the ant colony optimization (ACO). Besides, particular restrictions on the ACR are pointed out and the three causes of ant being-stuck problem are obtained. Furthermore, this article proposes a new ant searching mechanism through dual path-checking and online routing loop removing by every intermediate node an ant visited and the destination host respectively, to solve the problem of ant being stuck and routing loop simultaneously. The result of numerical simulation is abstracted from one real network. Compared with existing two typical ACR algorithms, it shows that the proposed algorithm can settle the problem of ant being stuck and achieve more effective searching outcome for optimization path.
李钝,MA Yong-tao, GUO Jian-li
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60188-0
摘要 ( 2133 ) PDF (145 KB)( 494 )
Based on the text orientation classification, a new measurement approach to semantic orientation of words was proposed. According to the integrated and detailed definition of words in HowNet, seed sets including the words with intense orientations were built up. The orientation similarity between the seed words and the given word was then calculated using the sentiment weight priority to recognize the semantic orientation of common words. Finally, the words’ semantic orientation and the context were combined to recognize the given words’ orientation. The experiments show that the measurement approach achieves better results for common words’ orientation classification and contributes particularly to the text orientation classification of large granularities.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60189-2
摘要 ( 3043 ) PDF (132 KB)( 481 )
The mismatch between the structured peer-to-peer (P2P) overlay network, which is based on Hashing, and the actual physical network, leads to query repeatedly passing through some nodes in the actual route when it is applied in Ad-hoc networks. An approach of getting an appropriate node identifier (ID) bearing its local physical information is proposed, in which the traditional theory of getting node ID through Hashing the node’s Internet protocol (IP) address is abandoned, and a topology-aware overlay network suiting Ad-hoc networks is constructed. The simulation results show that the overlay network constructed in the proposed method can avoid the route being iteratively accessed. Meanwhile, it can effectively minimize the latency and improve the load balance.
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60190-9
摘要 ( 2190 ) PDF (148 KB)( 440 )
A novel scheme for scalable video coding using three-band lifting-based motion-compensated transform is presented in this article. A series of flexible three-band motion-compensated lifting steps are used to implement the temporal wavelet transform, which provide improved compression performance by selecting specific motion model according to real video sequences, and offer higher temporal scalability flexibility by using three-band lifting steps. The experimental results compared with motion picture expert group (MPEG)-4 codec concerning standard video sequences demonstrate the effectiveness of the method.
陈黎明, ZOU Xue-cheng, LEI Jian-ming, LIU Zheng-lin
中国邮电高校学报(英文版), 2009, 16 (1). doi： 10.1016/S1005-8885(08)60191-0
摘要 ( 2836 ) PDF (289 KB)( 418 )
This article proposes a mechanism of low overhead and less runtime, termed dynamic cache resources allocation (DCRA), which allocates each application with required cache resources. The mechanism collects cache hit-miss information at runtime and then analyzes the information and decides how many cache resources should be allocated to the current executing application. The amount of cache resources varies dynamically to reduce the total number of misses and energy consumption. The study of several applications from SPEC2000 shows that significant energy saving is achieved for the application based on the DCRA with an average of 39% savings.