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Mathematical demonstration of correlation of optical prime code 被引量:1
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作者 李传起 张明德 孙小菡 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期153-158,共6页
Starting from the configuration of the optical prime code, a kind of key signature code for the optical code-division multiple access (OCDMA) system, based on the linear congruence theory in the finite Galois field,... Starting from the configuration of the optical prime code, a kind of key signature code for the optical code-division multiple access (OCDMA) system, based on the linear congruence theory in the finite Galois field, the correlation properties of the basic prime code, the extended prime code and the modified prime code are mathematically analyzed, the distribution of cross-correlation values is given and the overlap area of "1"s in the case of periodically circularly shifting is indicated. It is mathematically demonstrated that the maximum cross-correlation of the basic prime code is 2, and that of the extended prime code and the modified prime code is 1. The integrated correlation analysis process is proposed. The signal-interfere ratio (SIR) and the BER performance of the systems employing different signature codes are calculated, respectively, and the performances of OCDMA systems employing different signature codes mode are compared. 展开更多
关键词 fiber-optic communication optical code-division multiple access optical prime code CORRELATION
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ANALYSIS OF SPECTRAL PHASE ENCODING OCDMA SYSTEM WITH PSEUDORANDOM CODING 被引量:2
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作者 张海滨 宋文涛 +1 位作者 黄培中 李荣玉 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第1期1-3,共3页
Multiple access interference (MAI) is the most serious interference in spectral phase encoding optical code division multiple access (SPE OCDMA) systems. This paper focuses on the behavior of MAI in SPE OCDMA systems ... Multiple access interference (MAI) is the most serious interference in spectral phase encoding optical code division multiple access (SPE OCDMA) systems. This paper focuses on the behavior of MAI in SPE OCDMA systems with pseudorandom coding. The statistical expectation of multi access interference (MAI) is derived and plotted. The results confirm that MAI can be suppressed effectively by pseudorandom coding with m sequences. 展开更多
关键词 optical code-division MULTIPLE-ACCESS (OCDMA) SPECTRAL phase encoding M-SEQUENCES MULTIPLE-ACCESS inteference (MAI)
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JOINT SPACE-FREQUENCY MULTIUSER SYMBOL DETECTOR FOR MC-CDMA SYSTEM WITH UNIFORM LINEAR ARRAY 被引量:3
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作者 Wu Xiaojun Yin Qinye Feng Aigang Zhao Zheng Zhang Jianguo(institute of Information Engineering, Xi’an Jinotong University, Xi’an 710049) 《Journal of Electronics(China)》 2002年第4期337-345,共9页
The MultiCarrier Code Division Multiple Access (MC-CDMA) scheme is promising for relieving capacity limit problems of Direct Sequence (DS-) CDMA systems due to serious InterChip Interference (ICI) and MultiUser Interf... The MultiCarrier Code Division Multiple Access (MC-CDMA) scheme is promising for relieving capacity limit problems of Direct Sequence (DS-) CDMA systems due to serious InterChip Interference (ICI) and MultiUser Interference (MUI) in high-data-rate wireless communication systems. In this paper, the Uniform Linear Array (ULA) is applied to the base station of macrocellular MC-CDMA systems in a frequency-selective fading channel environment. A joint space-frequency multiuser symbol sequence detector is developed for all active users within one macrocell without space-frequency channel estimation. Simultaneously, Directions-Of-Arrivals (DOAs) of all active users can also be estimated. By dividing the ULA into two identical overlapping subarrays, a specific auxiliary matrix is constructed, which includes both symbol sequence and DOA information of all active users. Then, based on the subspace method, performing the eigen decomposition on such auxiliary matrix, the closed-form solution of symbol sequences and DOAs for all active users can be obtained. In comparison with schemes based on channel estimation, our algorithm need not explicitly estimate the space-frequency channel for each active user,so it has lower computation complexity. Extensive computer simulations demonstrate the overall performance of this novel scheme. 展开更多
关键词 Multicarricr code-division multiple access Frequency-selective fading Multiuser detector Uniform linear array Space-frequency channel DIRECTION-OF-ARRIVAL
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THE PERFORMANCE OF MT-CDMA SYSTEM IN THE PRESENCE OF CARRIER FREQUENCY OFFSET 被引量:1
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作者 Huang Ying Yang Wei Liu Junying 《Journal of Electronics(China)》 2007年第1期128-132,共5页
In this letter,the sensitivity of an uplink Multi-Tone Code-Division Multiple Access (MT-CDMA) system to the Carrier Frequency Offset (CFO) is investigated. The analytical expression for the Bit Error Rate (BER) of up... In this letter,the sensitivity of an uplink Multi-Tone Code-Division Multiple Access (MT-CDMA) system to the Carrier Frequency Offset (CFO) is investigated. The analytical expression for the Bit Error Rate (BER) of uplink MT-CDMA in the presence of CFO is derived in a multipath Rayleigh fading channel which is verified through simulations. Both Maximal Ratio Combining (MRC) and Equal Gain Combining (EGC) are considered in combining multipath signals in the analysis. It is found that the BER performance can be improved with the number of multipath increasing in the presence of CFO. 展开更多
关键词 MultiCarrier (MC) code-division Multiple Access (CDMA) Carrier Frequency Offset (CFO)
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AN OPTIMIZED SCHEME FOR FAST HANDOFF IN IP-BASED CDMA WIRELESS COMMUNICATION NETWORKS
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作者 DUAN Shi-ping(段世平) +5 位作者 XU You-yun(徐友云) SONG Wen-tao(宋文涛) LUO Han-wen(罗汉文) 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第2期190-193,共4页
This paper proposed an optimized fast handoff scheme for real time applications in next generation IP based CDMA wireless networks. The idea is to utilize optimized IP multicasting handoff (based on PIM SM), which is ... This paper proposed an optimized fast handoff scheme for real time applications in next generation IP based CDMA wireless networks. The idea is to utilize optimized IP multicasting handoff (based on PIM SM), which is triggered by CDMA layer 2 functionality. An IP based cellular network model with WCDMA FDD air interface and IP based packet traffic is adopted. No special network entities and signaling for handoff are added in our network model. The simulation results show that low delay and low packet lost rate can be obtained. 展开更多
关键词 fast HANDOFF code-division MULTIPLE-ACCESS (CDMA) IP-BASED WIRELESS networks
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Fitness Landscape Analysis for Optimum Multiuser Detection Problem
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作者 WANG Shaowei ZHU Qiuping 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期1073-1076,共4页
Optimum multiuser detection (OMD) for CDMA systems is an NP-complete combinatorial optimization problem. Fitness landscape has been proven to be very useful for understanding the behavior of combinatorial optimizati... Optimum multiuser detection (OMD) for CDMA systems is an NP-complete combinatorial optimization problem. Fitness landscape has been proven to be very useful for understanding the behavior of combinatorial optimization algorithms and can help in predicting their performance. This paper analyzes the statistic properties of the fitness landscape of the OMD problem by performing autocorrelation analysis, fitness distance correlation test and epistasis measure. The analysis results explain why some random search algorithms are effective methods for OMD problem and give hints how to design more efficient randomized search heuristic algorithms for OMD. 展开更多
关键词 code-division multiple access EPISTASIS fitness landscape optimal nultiuser detection
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LOW-COMPLEXITY BLIND MULTIUSER DETECTION OF DS-CDMA SIGNAL IN DISPERSIVE CHANNELS
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作者 Lin Zhiqiang You Xiaohu Wang Yong(National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096) 《Journal of Electronics(China)》 2001年第4期330-336,共7页
The problem of blind multiuser detection in dispersive channels of Code-Division Multiple-Access (CDMA) in the presence of both Multiple-Access Interference (MAI) and InterSymbol Interference (ISI) is considered. In p... The problem of blind multiuser detection in dispersive channels of Code-Division Multiple-Access (CDMA) in the presence of both Multiple-Access Interference (MAI) and InterSymbol Interference (ISI) is considered. In practice, it is showed that by incorporating the desired user's signature waveform and the auxiliary vector, the information of the user can be identified using the suboptimal subspace method. The major contribution of this paper is to propose a minimum-mean-square-error detector with the suboptimal subspace-based blind technique for joint suppression of MAI and ISI in the dispersive CDMA channels. 展开更多
关键词 code-division MULTIPLE-ACCESS MULTIUSER detection MULTIPLE-ACCESS INTERFERENCE Intersymbol INTERFERENCE
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SVM multiuser detection based on heuristic kernel
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作者 杨涛 Hu Bo 《High Technology Letters》 EI CAS 2007年第2期189-193,共5页
A support vector machine (SVM) based multiuser detection (MUD) scheme in code-division multi- ple-access (CDMA) system is proposed. In this scheme, the equivalent support vector (SV) is obtained through a kern... A support vector machine (SVM) based multiuser detection (MUD) scheme in code-division multi- ple-access (CDMA) system is proposed. In this scheme, the equivalent support vector (SV) is obtained through a kernel sparsity approximation algorithm, which avoids the conventional costly quadratic pro-gramming (QP) procedure in SVM. Besides, the coefficient of the SV is attained through the solution to a generalized eigenproblem. Simulation results show that the proposed scheme has almost the same bit er-ror rate (BER) as the standard SVM and is better than minimum mean square error (MMSE) scheme. Meanwhile, it has a low comoutation complexity. 展开更多
关键词 kernel function support vector machine muhiuser detection code-division multiple-access
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A New Family of Optical Codes Based on Complementary Theory for OCDMA System
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作者 Xing Chen Weixiao Meng 《Communications and Network》 2013年第3期176-180,共5页
A new family of optical codes for Optical Code-division Multiple Access (OCDMA) systems, named as Optical Complementary Codes (OCCs), is proposed in this paper. The constructions of these codes consist of multiple sub... A new family of optical codes for Optical Code-division Multiple Access (OCDMA) systems, named as Optical Complementary Codes (OCCs), is proposed in this paper. The constructions of these codes consist of multiple sub-codes, and the codes have an auto-correlation interference constraint as 0 and a cross-correlation interference constraint as 1. Compared with conventional optical codes such as OPCs, OOCs and 2-D OOCs, the OCC has a shorter code length and higher code efficiency with better correlation property. 展开更多
关键词 OPTICAL code-division Multiple Access (OCDMA) COMPLEMENTARY Code
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BLIND MULTIUSER DETECTION FOR V-BLAST CODED MULTICARRIER CDMA SYSTEM
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作者 Deng Ke Yin Qinye Zhang Hong 《Journal of Electronics(China)》 2006年第1期14-19,共6页
Focusing on the space-time coded multiuser mobile communication systems in the frequency-selective fading environment, this paper proposes a Vertical Bell labs LAyered Space-Time (V-BLAST) coded Multicarrier Code-Divi... Focusing on the space-time coded multiuser mobile communication systems in the frequency-selective fading environment, this paper proposes a Vertical Bell labs LAyered Space-Time (V-BLAST) coded Multicarrier Code-Division Multiple-Access (MC-CDMA) scheme and its blind channel identification algorithm. This algorithm employs an ESPRIT-like method and the singular value decomposition, and the channels between every transmit antenna of every user and every receive antenna of the base station are blindly estimated with a closed-form solution. Based on it, an equivalent Minimum Mean-Squared Error (MMSE) time-domain multiuser detector is derived. Moreover, the proposed scheme exploits the precoding in the transmitter in order to eliminate the constraint of more receive antennas than transmit ones, required by most conventional V-BLAST codec schemes. Computer simulation results demonstrate the validity of this proposed scheme. 展开更多
关键词 MULTICARRIER code-division multiple-access Vertical Bell labs layered space-time code Multiuser detection
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SUCCESSIVE BEAMFORMING,MULTIUSER DETECTION AND DIVERSITY RECEPTION FOR MULTICARRIER DS-CDMA SYSTEM WITH ANTENNA ARRAY
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作者 Yang Wei Chen Junshi +1 位作者 Tan Zhenhui Cheng Shixin 《Journal of Electronics(China)》 2007年第5期607-612,共6页
Code-Division Multiple-Access (CDMA) systems are interference limited,and therefore efficient interference management is necessary to enhance the performance of a CDMA system.In this paper,a successive beamforming (sp... Code-Division Multiple-Access (CDMA) systems are interference limited,and therefore efficient interference management is necessary to enhance the performance of a CDMA system.In this paper,a successive beamforming (spatial filtering),linear decorrelating MultiUser Detection (MUD, temporal filtering) and diversity reception structure for uplink multicarrier Direct Sequence CDMA (DS-CDMA) system with antenna array are proposed.By beamforming,the antenna array suppresses interference according to the distinct array signature.Subsequently,linear decorrelating MUD is ap- plied to separate the signals of different users and eliminate Multiple Access Interference (MAI).Finally, the decorrelated signals at different subcarriers that belong to the same user are combined to achieve frequency diversity.Simulation results show that the proposed structure offers significant Bit Error Rate (BER) performance improvement by successively exploiting the space-time-frequency processing. 展开更多
关键词 Antenna array Multicarrier Direct Sequence code-division Multiple-Access (DS-CDMA) MultiUser Detection (MUD) Diversity
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Equivalent Time-Domain Representation and Uplink Channel Estimator for Multicarrier CDMA Systems
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作者 吴晓军 殷勤业 曾明 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第3期1-7,共7页
Many blind channel estimation methods have been proposed for direct sequence (DS) code-division multiple access (CDMA) systems, so we can certainly use them to estimate the finite impulse response (FIR) channel for th... Many blind channel estimation methods have been proposed for direct sequence (DS) code-division multiple access (CDMA) systems, so we can certainly use them to estimate the finite impulse response (FIR) channel for the multi-carrier (MC-) CDMA system. In this paper, the MC-CDMA system is interpreted as an equivalent time-domain DS-CD-MA system with specific spreading codes. Then, an equivalently time-domain blind channel estimator is derived for the uplink MC-CDMA, which is based on second-order statistics of the received data. By exploiting singular value decomposition (SVD) and the finite alphabet property of transmitted symbols, the time-domain channel impulse response (CIR) for the uplink MC-CDMA can be accurately identified. Computer simulations illustrate both the validity and the overall performance of the proposed estimator. 展开更多
关键词 Multicarrier code-division multiple access Channel impulse response Multiple access interference Intersym-bol interference Cyclic prefix Blind channel estimation Multiuser detection.
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Tunable Super-Structured Fiber Bragg Gratings with Perfect Sequences Based on m-Sequence
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作者 Joao S.Pereira Marco P.M.Ferreira Marko Gasparovic 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第4期358-363,共6页
Recently, a tunable fiber Bragg grating(FBG) was developed by using stress-responsive colloidal crystals. In this paper, we have simulated the application of these nanoparticles into the super-structured fiber Bragg g... Recently, a tunable fiber Bragg grating(FBG) was developed by using stress-responsive colloidal crystals. In this paper, we have simulated the application of these nanoparticles into the super-structured fiber Bragg grating(SSFBG) written with perfect sequences derived from a short maximal-length sequence. A tunable SSFBG will be available to overcome the prohibitive temperature variation of the optical codecs. Nevertheless,we presented a method to implement coherent time spreading optical code-division multiple-access(OCDMA) where a unique code(or perfect sequence) can be reused and mixed with different wavelengths to obtain a tunable wavelength-division multiplexing(WDM)system. In order to maximize the binary throughput, we have selected a unique short maximal-length sequence composed of 7 chips that can be tuned with 7 different optical wavelengths. We found thousands of different tunable combinations that presented power contrast ratios(P/C) higher than 12 dB. When a WDM-OCDMA system used 2 different combinations simultaneously, the perfect binary detection with error correction codes was achieved successfully. The tunable SSFBG with colloidal crystals will be a simple and good alternative choice for fiber-to-the-home(FTTH) communications. 展开更多
关键词 Optical code-division multiple-access(OCDMA) super-structured fiber Bragg grating(SSFBG) wavelength-division multiplexing OCDMA(WDM-OCDMA)
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HYBRID ORTHOGONAL/RANDOM MULTIPLE ACCESS SCHEME WITH IMPROVED PERFORMANCE FOR DOWNLINK CDMA SYSTEMS
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作者 Zhou Gao Fan Pingzhi Hao Li 《Journal of Electronics(China)》 2008年第1期47-52,共6页
In this paper, a hybrid orthogonal and random multiple access scheme with improved performance for capacity-enhanced downlink Code-Division Multiple-Access (CDMA) systems is presented, which is in fact a combination o... In this paper, a hybrid orthogonal and random multiple access scheme with improved performance for capacity-enhanced downlink Code-Division Multiple-Access (CDMA) systems is presented, which is in fact a combination of the conventional orthogonal spreading scheme and the synchronous Interleave Division Multiple Access (IDMA) scheme. The proposed scheme can achieve near single user performance for very large number of users by the iterative turbo like detection. Analysis and simulation results show that the proposed scheme performs better than the synchronous IDMA scheme for the same time complexity. Meanwhile, larger capacity can be provided compared with the conventional orthogonal schemes. 展开更多
关键词 code-division Multiple-Access (CDMA) Interleave-Division Multiple-Access (IDMA) Multi-User Detection (MUD) Hybrid multiple access
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PDA DETECTOR FOR DS-CDMA COOPERATIVE SYSTEM
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作者 Mei Zhonghui Meng Qingmin +1 位作者 Li Xiaofei Wu Lenan 《Journal of Electronics(China)》 2009年第6期812-818,共7页
This paper considers the uplink of a cooperative Code-Division Multiple-Access (CDMA) system where parts of mobile nodes serve as source nodes while the others serve as relay nodes at any instant in time. When the non... This paper considers the uplink of a cooperative Code-Division Multiple-Access (CDMA) system where parts of mobile nodes serve as source nodes while the others serve as relay nodes at any instant in time. When the non-orthogonal spreading codes are adopted,Multiple Access Interference (MAI) will exist at both the relay nodes and the base node,causing diversity gain to diminish. To mitigate MAI and exploit full advantages of cooperation,the Probabilistic Data Association (PDA) is developed at the relay nodes and the base node. Simulation results demonstrate that some performance gains can be obtained by the PDA detector over the Minimum Mean Square Error (MMSE) detector at high Signal-to-Noise Ratio (SNR) and conversely at low SNR. 展开更多
关键词 Cooperative communication Multiuser detection Probabilistic Data Association (PDA) code-division Multiple-Access (CDMA)
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A Particle Filter of Blind Equalization and Multiuser Detection in Asynchronous DS/CDMA Systems
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作者 张静 董建萍 张谦 《Journal of Donghua University(English Edition)》 EI CAS 2008年第3期263-268,共6页
The particle filter (PF) is proposed to be the asynchronous direct-sequence code-division multiple-access (DS/CDMA) multiuser detector without knowing the channel state information. The PF performs symbol detectio... The particle filter (PF) is proposed to be the asynchronous direct-sequence code-division multiple-access (DS/CDMA) multiuser detector without knowing the channel state information. The PF performs symbol detection according to the joint posterior density probability of simulated particles including relative delays, fading gains and symbols via sequential importance sample and resample. A simplified scheme is also proposed by separating the indepent relative delays and fading with symbols. These parameters are modeled as the extended aggressive processes and estimated by the Kalman filter, so as to provide their arbitrary distribution for symbol detection. Simulation results show that the bit error rate of the PF is less than conventional detectors. Moreover, the complexity of PF is moderate comparable to other nonlinear suboptimal approaches. 展开更多
关键词 code-division multiple-access CDMA) spread spectrum multiuser detection interference suppression channel estimation sequential Monte Carlo particle filter
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THE STUDY OF AN M-ARY MC-CDMA SYSTEM BASED ON CYCLIC SPREADING CODES & PRE-EQUALIZATION
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作者 ChuZhenyong YingXiaofan +1 位作者 YiKechu TianHongxin 《Journal of Electronics(China)》 2005年第3期273-280,共8页
A novel fast despreading scheme for M-ary Multi-Carrier Code-Division Multiple Access (MC-CDMA) system is proposed based on cyclic spreading codes and pre-equalizer. In the transmitter, the M spreading codes of each u... A novel fast despreading scheme for M-ary Multi-Carrier Code-Division Multiple Access (MC-CDMA) system is proposed based on cyclic spreading codes and pre-equalizer. In the transmitter, the M spreading codes of each user are generated by circularly shifting the prototype spreading code. A feedback pre-equalizer is employed to process the M-ary MC- CDMA signal before transmitted. The received signal is multiplied by the Inverse Discrete Fourier Transform (IDFT) result of the mirror image code of the prototype spreading code, and then demodulated by Orthogonal Frequency-Division Multiplexing (OFDM) demodulator. Compared with the conventional M-ary MC-CDMA receiver, the proposed scheme increases bandwidth efficiency, meanwhile, it achieves M-ary despread spectrum and multi-carrier demodulation, which reduces computation complexity remarkably. 展开更多
关键词 Multi-Carrier code-division Multiple Access (MC-CDMA) M-ary spread spec- trum Cyclic spreading codes PRE-EQUALIZATION Computation complexity
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The Application of Optical CDMA-Based Fiber Radio Networks in Wireless Sensor Networks
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作者 Chao-Chin YANG 《Wireless Sensor Network》 2009年第2期61-67,共7页
One fiber radio scheme using shifted prime codes for interference elimination is proposed for optical code-division multiple-access (OCDMA) network. By taking advantage of the cyclic property of the shifted prime code... One fiber radio scheme using shifted prime codes for interference elimination is proposed for optical code-division multiple-access (OCDMA) network. By taking advantage of the cyclic property of the shifted prime codes in the same code groups, the proposed compact decoder is low cost and suitable to be used in the task manager node in the applications of wireless sensor networks. The performance comparison for sev-eral OCDMA-based fiber radio networks is also given to clarify the advantage of the proposed one. 展开更多
关键词 OPTICAL code-division MULTIPLE-ACCESS (OCDMA) Passive OPTICAL Network (PON) Arrayed Waveguide Grating (AWG) PRIME Code
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BER Performance of Space-Time Coded MMSE DFE for Wideband Code Division Multiple Access (WCDMA)
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作者 Sanjay Kumar SHARMA S. Naseem AHMAD 《International Journal of Communications, Network and System Sciences》 2009年第4期276-282,共7页
In recent times, there has been growing interests in integration of voice, data and video traffic in wireless communication networks. With these growing interests, WCDMA has immerged as an attractive access technique.... In recent times, there has been growing interests in integration of voice, data and video traffic in wireless communication networks. With these growing interests, WCDMA has immerged as an attractive access technique. The performance of WCDMA system is deteriorated in presence of multipath fading environment. The paper presents space-time coded minimum mean square error (MMSE) Decision Feedback Equalizer (DFE) for wideband code division multiple access (WCDMA) in a frequency selective channel. The filter coefficients in MMSE DFE are optimized to suppress noise, intersymbol interference (ISI), and multiple access interference (MAI) with reasonable system complexity. For the above structure, we have presented the estimation of BER for a MMSE DFE using computer simulation experiments. The simulation includes the effects of additive white Gaussian noise, multipath fading and multiple access interference (MAI). Furthermore, the performance is compared with standard linear equalizer (LE) and RAKE receiver. Numerical and simulation results show that the MMSE DFE exhibits significant performance improvement over the standard linear equalizer (LE) and RAKE receiver. 展开更多
关键词 Decision Feedback EQUALIZER Multiple Access Interference (MAI) RAKE Receiver Transmit Diversity Wideband code-division MULTIPLE-ACCESS (WCDMA) Bit Error Rate (BER)
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QPSK DS-CDMA System over Rayleigh Channel with a Randomly-Varying Frequency Narrow-Band Interference: Frequency Tracking Analysis
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作者 Aloys N. Mvuma 《Wireless Sensor Network》 2010年第3期243-249,共7页
This paper analyses frequency tracking characteristics of a complex-coefficient adaptive infinite-impulse response (IIR) notch filter used for suppression of narrow-band interference (NBI) with a randomly-varying freq... This paper analyses frequency tracking characteristics of a complex-coefficient adaptive infinite-impulse response (IIR) notch filter used for suppression of narrow-band interference (NBI) with a randomly-varying frequency in a quadriphase shift keying (QPSK) modulated direct-sequence code-division multiple-access (DS-CDMA) communication system. The QPSK DS-CDMA signals are transmitted over a frequency non-selective Rayleigh fading channel. The analysis is based on a first-order real-coefficient difference equation with respect to steady-state instantaneous frequency tracking error from which a closed-form expression that relates frequency tracking mean square error (MSE) with number of DS-CDMA active users and NBI power is obtained. Closed-form expressions for optimum notch bandwidth coefficient and step size constant that minimize the frequency tracking MSE are also derived. Computer simulations are included to substantiate the accuracy of the analyses. 展开更多
关键词 code-division Multiple Access (CDMA) Quadriphase Shift Keying (QPSK) Complex Adaptive IIR Notch Filter NARROW-BAND Interference (NBI) FREQUENCY Tracking MSE
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