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Linear Dispersion Orthogonal Space-Time Block Codes
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作者 高明 葛建华 李靖 《Journal of Beijing Institute of Technology》 EI CAS 2010年第3期357-361,共5页
A new architecture of space-time codes as a combination of orthogonal space-time block codes (OSTBC) and linear dispersion codes (LDC) is proposed in order to improve the bit error rate(BER) performance of OSTBC... A new architecture of space-time codes as a combination of orthogonal space-time block codes (OSTBC) and linear dispersion codes (LDC) is proposed in order to improve the bit error rate(BER) performance of OSTBC.The scheme proposed is named linear dispersion orthogonal space-time block codes (LDOSTBC).In LDOSTBC scheme,firstly,the data is coded into LDC codewords.Then,the coded LDC substreams are coded into OSTBC codewords again.The decoding algorithm of LDOSTBC combines linear decoding of OSTBC and ML decoding or suboptimum detection algorithms of LDC.Compared with OSTBC scheme when the rate of LDC is MtR,the performance of LDOSTBC scheme can be improved without decreasing the data rate,where Mt is the number of transmit antennas and R is the spectral efficiency of the modulation constellation.If some rate penalty is allowed,when the rate of LDC is less than MtR the performance of LDOSTBC can be improved further. 展开更多
关键词 space-time coding linear dispersion codes (LDC) orthogonal space-time block codes (OSTBC)
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Differential modulation based on space-time block codes
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作者 李正权 胡光锐 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第3期407-412,共6页
A differential modulation scheme using space-time block codes is put forward. Compared with other schemes, our scheme has lower computational complexity and has a simpler decoder. In the case of three or four transmit... A differential modulation scheme using space-time block codes is put forward. Compared with other schemes, our scheme has lower computational complexity and has a simpler decoder. In the case of three or four transmitter antennas, our scheme has a higher rate a higher coding gain and a lower bit error rate for a given rate. Then we made simulations for space-time block codes as well as group codes in the case of two, three, four and five transmit antennas. The simulations prove that using two transmit antennas, one receive antenna and code rate of 4 bits/s/Hz, the differential STBC method outperform the differential group codes method by 4 dB. Useing three, four and five transmit antennas, one receive antenna, and code rate of 3 bits/s/Hz are adopted, the differential STBC method outperform the differential group codes method by 5 dB, 6. 5 dB and 7 dB, respectively. In other words, the differential modulation scheme based on space-time block code is better than the corresponding differential modulation scheme 展开更多
关键词 space-time block code coding gain differential modulation bit error rate.
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A New Generalized Complex Orthogonal Space-Time Block Codes
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作者 单红梅 胡光锐 《Journal of Shanghai University(English Edition)》 CAS 2005年第3期241-243,共3页
Recent research challenges in the wireless communication include the usage of diversity and efficient coding to improve data transmission quality and spectral efficiency. Space diversity uses multiple transmitting and... Recent research challenges in the wireless communication include the usage of diversity and efficient coding to improve data transmission quality and spectral efficiency. Space diversity uses multiple transmitting and/or receiving antennas to create independent fading channels without penalty in bandwidth efficiency. Space-time block coding is an encoding scheme for communication over Rayleigh fading channels using multiple transmitting antennas. Space-time block codes from complex orthogonal designs exist only for two transmitting antennas. This paper generalizes a new complex orthogonal space-time block code for four transmitting antennas, whose decoding complexity is very low. Simulations show that the generalized complex orthogonal space-time block code has low bit error rate, full rate and possibly large diversity. 展开更多
关键词 space diversity space-time block code multiple antennas generalized complex orthogonal designs.
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Space-time Block Codes Based on Quasi-Orthogonal Designs
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作者 李正权 胡光锐 单红梅 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期4-7,共4页
A new space-time block codes based on quasi-orthogonal designs are put forward. First the channel model is formulated. Then the connection between orthogonal /quasi-orthogonal designs and space-time block codes is exp... A new space-time block codes based on quasi-orthogonal designs are put forward. First the channel model is formulated. Then the connection between orthogonal /quasi-orthogonal designs and space-time block codes is explored. Finally we make simulations for the transmission of 4 bits/s/Hz and 6 bits/s/Hz using eight transmit antennas using the rate 3/4 quasi-orthogonal space-time block code and the rate 1/2 full-diversity orthogonal space-time block code. Simulation results show that full transmission rate is more important for very low signal noise ratio (SNR) and high bit error probability (BEP), while full diversity is more important for very high SNR and low BEP. 展开更多
关键词 space-time block code orthogonal design quasi-orthogonal.
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EXACT ERROR PROBABILITY OF ORTHOGONAL SPACE-TIME BLOCK CODES OVER FLAT FADING CHANNELS
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作者 Xu Feng Yue Dianwu 《Journal of Electronics(China)》 2007年第4期462-469,共8页
Space time block coding is a modulation scheme recently discovered for the transmit an- tenna diversity to combat the effects of wireless fading channels. Using the equivalent Single-Input Single-Output (SISO) model, ... Space time block coding is a modulation scheme recently discovered for the transmit an- tenna diversity to combat the effects of wireless fading channels. Using the equivalent Single-Input Single-Output (SISO) model, this paper presents closed-form expressions for the exact Symbol Error Rate (SER) and Bit Error Rate (BER) of Orthogonal Space-Time Block Codes (OSTBCs) with M-ary Phase-Shift Keying (MPSK) and M-ary Quadrature Amplitude Modulation (MQAM) over flat un- correlated Nakagami-m and Ricean fading channels. 展开更多
关键词 Orthogonal space-time block code (OSTBC) Nakagami-m fading channel Ricean fading channel
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Bit Error Rate (BER) Performance Evaluation of Various Space-time Block Codes in MIMO Wireless Communications
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作者 Sanjay Kumar Sharma Syed Naseem Ahmad 《通讯和计算机(中英文版)》 2010年第3期32-38,共7页
关键词 空时分组码 无线通信 MIMO BER 误码率 评价 性能
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Capacity of orthogonal space-time block codes in MISO fading channels with co-channel interference and noise 被引量:2
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作者 YUE DianWu WANG Qian 《Science in China(Series F)》 2009年第9期1697-1703,共7页
Orthogonal space-time block codes (OSTBCs) are an efficient mean in order to exploit the diversity offered by the wireless multiple-input multiple-output (MIMO) channel. This paper considers capacity problems of O... Orthogonal space-time block codes (OSTBCs) are an efficient mean in order to exploit the diversity offered by the wireless multiple-input multiple-output (MIMO) channel. This paper considers capacity problems of OSTBCs over spatially correlated multiple-input single-out (MISO) Rayleigh fading channels in the presence of spatially correlated Rayleigh co-channel interference and additive Gaussian noise, and derives exact expressions of the ergodic capacity and outage probability (capacity distribution) for such OSTBCs. Some numerical examples are given to illustrate the effect of co-channel interference on the ergodic and outage capacity of OSTBCs. 展开更多
关键词 multiple-input single-output orthogonal space-time block code capacity co-channel interference noise
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A Theoretical Method for Estimating Performance of Reed-Solomon Codes Concatenated with Orthogonal Space-Time Block Codes 被引量:3
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作者 LUOTao HAOJian-Jun 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2002年第1期30-34,共5页
Based on the studies of Reed-Solomon codes and orthogonalspace-time block codes over Rayleigh fading channel, a theoreticalmethod for estimating performance of Reed-Solomon codes concatenatedwith orthogonal space- tim... Based on the studies of Reed-Solomon codes and orthogonalspace-time block codes over Rayleigh fading channel, a theoreticalmethod for estimating performance of Reed-Solomon codes concatenatedwith orthogonal space- time block codes is presented in this paper.And an upper bound of the bit error rate is also obtained. It isshown through computer simulations that the signal-to-noise ratioreduces about 15 dB or more after orthogonal space-time block codesare concatenate with Reed-Solomon(15,6)codes over Rayleigh fadingchannel, when the bit error rate is 10^-4. 展开更多
关键词 channel codes space-time codes concatenated codes diversity technology
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Design of super-orthogonal space-time trellis codes based on trace criterion
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作者 耿嘉 曹秀英 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期456-460,共5页
A design of super-orthogonal space-time trellis codes (SOSTTCs) based on the trace criterion (TC) is proposed for improving the design of SOSTTCs. The shortcomings of the rank and determinant criteria based design... A design of super-orthogonal space-time trellis codes (SOSTTCs) based on the trace criterion (TC) is proposed for improving the design of SOSTTCs. The shortcomings of the rank and determinant criteria based design and the advantages of the TC-based design are analyzed. The optimization principle of four factors is presented, which includes the space-time block coding (STBC) scheme, set partitioning, trellis structure, and the assignment of signal subsets and STBC schemes in the trellis. According to this principle, systematical and handcrafted design steps are given in detail. By constellation expansion, the code performance can be further improved. The code design results are given, and the new codes outperform others in the simulation. 展开更多
关键词 super-orthogonal space-time trellis codes trace criterion handcrafted and systematical design
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An Improved Group Space-Time Block Code Through Constellation Rotation 被引量:1
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作者 ZHANG Hong-wei(张红伟) +7 位作者 ZHANG Hai-bin(张海滨) SONG Wen-tao(宋文涛) LUO Han-wen(罗汉文) LIU Xing-zhao(刘兴钊) 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第4期349-353,共5页
A new improved group space-time block code (G-STBC) based on constellation rotation for four transmit antennas was proposed. In comparison with the traditional G-STBC coding scheme, the proposed space-time code has lo... A new improved group space-time block code (G-STBC) based on constellation rotation for four transmit antennas was proposed. In comparison with the traditional G-STBC coding scheme, the proposed space-time code has longer code length and adopts proper rotation-based symbols, which can increase the minimum distance of space-time codes and thereby improve code gain and achieve full diversity performance. The simulation results verify that the proposed group space-time code can achieve better bit error performance than both the traditional group space-time code and other quasi-orthogonal space-time codes. Compared with Ma’s full diversity full rate (FDFR) codes, the proposed space-time code also can achieve the same excellent error performance. Furthermore, the design of the new space-time code gives another new and simple method to construct space-time codes with full diversity and high rate in case that it is not easy to design the traditional FDFR space-time codes. 展开更多
关键词 group space-time block code constellation rotation multiple-input multiple-output (MIMO) full diversity full rate
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Joint channel estimation and symbol detection for space-time block code
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作者 单淑伟 罗汉文 宋文涛 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第3期266-269,共4页
The simplified joint channel estimation and symbol detection based on the EM (expectation-maximization) algorithm for space-time block code (STBC) are proposed. By assuming channel to be invariant within only one STBC... The simplified joint channel estimation and symbol detection based on the EM (expectation-maximization) algorithm for space-time block code (STBC) are proposed. By assuming channel to be invariant within only one STBC word and utilizing the orthogonal structure of STBC, the computational complexity and cost of this algorithm are both very low, so it is very suitable to implementation in real systems. 展开更多
关键词 space-time block code expectation-maximization algorithm channel estimation symbol detection.
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UNIT-RATE COMPLEX ORTHOGONAL SPACE-TIME BLOCK CODE CONCATENATED WITH TURBO CODING
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作者 Yu Xiangbin Bi Guangguo 《Journal of Electronics(China)》 2006年第3期346-349,共4页
Space-Time Block (STB) code has been an effective transmit diversity technique for combating fading due to its orthogonal design, simple decoding and high diversity gains. In this paper, a unit-rate complex orthogonal... Space-Time Block (STB) code has been an effective transmit diversity technique for combating fading due to its orthogonal design, simple decoding and high diversity gains. In this paper, a unit-rate complex orthogonal STB code for multiple antennas in Time Division Duplex (TDD) mode is proposed. Meanwhile, Turbo Coding (TC) is employed to improve the performance of proposed STB code further by utilizing its good ability to combat the burst error of fading channel. Compared with full-diversity multiple antennas STB codes, the proposed code can implement unit rate and partial diversity; and it has much smaller computational complexity under the same system throughput. Moreover, the application of TC can effectively make up for the performance loss due to partial diversity. Simulation results show that on the condition of same system throughput and concatenation of TC, the proposed code has lower Bit Error Rate (BER) than those full-diversity codes. 展开更多
关键词 space-time block (STB) codes Turbo-Coding (TC) Unit-rate Multiple antennas Transmit diversity
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Adaptive OFDM system based on space-time block code
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作者 孙绪宝 钟顺时 《Journal of Shanghai University(English Edition)》 CAS 2006年第5期421-424,共4页
To satisfy the request of wireless communication for new generation communication system, a new scheme consisting of a combination of adaptive technology and space-time code-OFDM is presented. The proposed method, exp... To satisfy the request of wireless communication for new generation communication system, a new scheme consisting of a combination of adaptive technology and space-time code-OFDM is presented. The proposed method, exploits adaptive bit allocation scheme over multipath fading channel. Numerical simulations have shown that the proposed scheme can greatly improve the performance of non-adaptive STBC-OFDM system. 展开更多
关键词 space-time coding ADAPTIVE transmit diversity.
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A Design Method of Noncoherent Unitary Space-Time Codes
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作者 Li Peng Qiuping Peng Lingling Yang 《International Journal of Communications, Network and System Sciences》 2011年第7期430-435,共6页
We generalized an constructing method of noncoherent unitary space time codes (N-USTC) over Rayleigh flat fading channels. A family of N-USTCs with T symbol peroids, M transmit and N receive antennas was constructed b... We generalized an constructing method of noncoherent unitary space time codes (N-USTC) over Rayleigh flat fading channels. A family of N-USTCs with T symbol peroids, M transmit and N receive antennas was constructed by the exponential mapping method based on the tangent subspace of the Grassmann manifold. This exponential mapping method can transform the coherent space time codes (C-STC) into the N-USTC on the Grassmann manifold. We infered an universal framework of constructing a C-STC that is designed by using the algebraic number theory and has full rate and full diversity (FRFD) for t symbol periods and same antennas, where M, N, T, t are general positive integer. We discussed the constraint condition that the exponential mapping has only one solution, from which we presented a approach of searching the optimum adjustive factor αopt that can generate an optimum noncoherent codeword. For different code parameters M, N, T, t and the optimum adjustive factor αopt, we gave the simulation results of the several N-USTCs. 展开更多
关键词 NONCOHERENT Uintary space-time codes (N-USTC) Coherent space-time codes (C-STC) GRASSMANN Manifold Degree of Freedom Exponenatial Map Full Rate and Full Diversity (FRFD)
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REDUCED-COMPLEXITY DECODING ALGORITHMS FOR UNITARY SPACE-TIME CODES
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作者 Su Xin Yi Kechu +1 位作者 Tian Bin Sun Vongjun 《Journal of Electronics(China)》 2007年第1期112-115,共4页
Two reduced-complexity decoding algorithms for unitary space-time codes based on tree-structured constellation are presented. In this letter original unitary space-time constellation is divided into several groups. Ea... Two reduced-complexity decoding algorithms for unitary space-time codes based on tree-structured constellation are presented. In this letter original unitary space-time constellation is divided into several groups. Each one is treated as the leaf nodes set of a subtree. Choosing the unitary signals that represent each group as the roots of these subtrees generates a tree-structured constellation. The proposed tree search decoder decides to which sub tree the receive signal belongs by searching in the set of subtree roots. The final decision is made after a local search in the leaf nodes set of the se-lected sub tree. The adjacent subtree joint decoder performs joint search in the selected sub tree and its “surrounding” subtrees,which improves the Bit Error Rate (BER) performance of purely tree search method. The exhaustively search in the whole constellation is avoided in our proposed decoding al-gorithms,a lower complexity is obtained compared to that of Maximum Likelihood (ML) decoding. Simulation results have also been provided to demonstrate the feasibility of these new methods. 展开更多
关键词 Unitary space-time codes CONSTELLATION COMPLEXITY DECODING
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LOW RATE SPACE-TIME TRELLIS CODES INPOWER LIMITED WIRELESSCOMMUNICATION SYSTEMS
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作者 WuGang WangHafeng 《Journal of Electronics(China)》 2002年第3期241-247,共7页
Space-time trellis codes can achieve the best tradeoff among bandwidth efficiency, diversity gain, constellation size and trellis complexity. In this paper, some optimum low rate space-time trellis codes are proposed.... Space-time trellis codes can achieve the best tradeoff among bandwidth efficiency, diversity gain, constellation size and trellis complexity. In this paper, some optimum low rate space-time trellis codes are proposed. Performance analysis and simulation show that the low rate space-time trellis codes outperform space-time block codes concatenated with convolutional code at the same bandwidth efficiency, and are more suitable for the power limited wireless communication system. 展开更多
关键词 space-time trellis codes space-time transmit diversity Bandwidth efficiency
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A new design criterion and construction method for space-time trellis codes based on classification of error events
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作者 Qiang Yongquan(强永全) Wang Jiao Li Daoben 《High Technology Letters》 EI CAS 2005年第3期289-293,共5页
The known design criterions of Space-Time Trellis Codes (STFC) on slow Rayleigh fading channel are rank, determinant and trace criterion. These criterions are not advantageous not onlv in operation but also in perfo... The known design criterions of Space-Time Trellis Codes (STFC) on slow Rayleigh fading channel are rank, determinant and trace criterion. These criterions are not advantageous not onlv in operation but also in performance. With classifying the error events of STTC, a new criterion was presented on slow Rayleigh fading channels. Basod on the criterion, an effective and straighttbrward multi-step method is proposed to ennstruet codes with better performance. This method can reduce the computation of search to small enough. Simulation results show that the codes searched by computer have the same or even better performance than the repored codes. 展开更多
关键词 space-time trellis codes design criterion wireless communication
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Performance of Block Space-Time Code in Wireless Channel Dynamics
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作者 Won Mee JANG Jong Hak JUNG 《International Journal of Communications, Network and System Sciences》 2009年第6期461-468,共8页
In this work, we observe the behavior of block space-time code in wireless channel dynamics. The block space-time code is optimally constructed in slow fading. The block code in quasistatic fading channels provides af... In this work, we observe the behavior of block space-time code in wireless channel dynamics. The block space-time code is optimally constructed in slow fading. The block code in quasistatic fading channels provides affordable complexity in design and construction. Our results show that the performance of the block space-time code may not be as good as conventionally convolutional coding with serial transmission for some channel features. As channel approaches fast fading, a coded single antenna scheme can collect as much diversity as desired by correctly choosing the free distance of code. The results also point to the need for robust space-time code in dynamic wireless fading channels. We expect that self-encoded spread spec-trum with block space-time code will provide a robust performance in dynamic wireless fading channels. 展开更多
关键词 space-time codes DIVERSITY Multiple Transmit ANTENNAS Self-Encoded SPREAD SPECTRUM
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Low complexity suboptimal decode algorithms for quasi- orthogonal space time block codes
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作者 李正权 吴名 +2 位作者 沈连丰 王志功 贾子彦 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期1-5,共5页
Due to the high complexity of the pairwise decoding algorithm and the poor performance of zero forcing( ZF) /minimum mean square error( MMSE) decoding algorithm, two low-complexity suboptimal decoding algorithms, ... Due to the high complexity of the pairwise decoding algorithm and the poor performance of zero forcing( ZF) /minimum mean square error( MMSE) decoding algorithm, two low-complexity suboptimal decoding algorithms, called pairwisequasi-ZF and pairwise-quasi-MMSE decoders, are proposed. First,two transmit signals are detected by the quasi-ZF or the quasiMMSE algorithm at the receiver. Then, the two detected signals as the decoding results are substituted into the two pairwise decoding algorithm expressions to detect the other two transmit signals. The bit error rate( BER) performance of the proposed algorithms is compared with that of the current known decoding algorithms.Also, the number of calculations of ZF, MMSE, quasi-ZF and quasi-MMSE algorithms is compared with each other. Simulation results showthat the BER performance of the proposed algorithms is substantially improved in comparison to the quasi-ZF and quasiMMSE algorithms. The BER performance of the pairwise-quasiZF( pairwise-quasi-MMSE) decoder is equivalent to the pairwiseZF( pairwise-MMSE) decoder, while the computational complexity is significantly reduced. 展开更多
关键词 quasi-orthogonal space-time block code(QOSTBC) low-complexity decoding pairwise-quasi-ZF pairwise-quasi-MMSE bit error rate(BER)
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Method of combining space-time block coding with adaptive beamforming
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作者 沈克勤 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期254-259,共6页
A method of space-time block coding (STBC) system based on adaptive beamforming of cyclostationarity signal algorithm is proposed.The method uses cyclostationarity of signals to achieve adaptive beamforming,then con... A method of space-time block coding (STBC) system based on adaptive beamforming of cyclostationarity signal algorithm is proposed.The method uses cyclostationarity of signals to achieve adaptive beamforming,then constructs a pair of low correlated transmit beams based on beamform estimation of multiple component signals of uplink.Using these two selected transmit beams,signals encoded by STBC are transmitted to achieve diversity gain and beamforming gain at the same time,and increase the signal to noise ratio (SNR) of downlink.With simple computation and fast convergence performance,the proposed scheme is applicable for time division multiple access (TDMA) wireless communication operated in a complex interference environment.Simulation results show that the proposed scheme has better performance than conventional STBC,and can obtain a gain of about 5 dB when the bit error ratio (BER) is 10-4. 展开更多
关键词 space-time coding GAIN adaptive beamforming cyclostationary signal transmit diversity
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