A novel framework of which combines smart antennas multiple antenna systems, （SA） with multiple-inputmultiple-output （mimo） at the receiver, is proposed. The uplink SA-mimo system is investigated. The joint optim...
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A novel framework of which combines smart antennas multiple antenna systems, （SA） with multiple-inputmultiple-output （mimo） at the receiver, is proposed. The uplink SA-mimo system is investigated. The joint optimization problem corresponding to the uplink capacity of the single-user SA-mimo system is deduced. Then the closedform expression of the capacity is obtained in the case of equal power allocation and the same direction-of-arrivals （DOAs） from different transmit antennas at the same antenna array, and an upper bound of the capacity is also given in the case of different DOAs at the same antenna array. After that, for the general case, a suboptimal method for the capacity optimization problem is presented. Some numerical results are also given to compare the capacities of conventional mimo and SA-mimo systems and show that the proposed method is viable.
The dynamic resource allocation problem in high-speed railway downlink orthogonal frequency-division multiplexing（OFDM） systems with multiple-input multiple-output（mimo） antennas is ***-carriers,antennas,time slot...
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The dynamic resource allocation problem in high-speed railway downlink orthogonal frequency-division multiplexing（OFDM） systems with multiple-input multiple-output（mimo） antennas is ***-carriers,antennas,time slots,and power are jointly *** problem of multi-dimensional resource allocation is formulated as a mixed-integer nonlinear programming *** effect of the moving speed on Doppler shift is analyzed to calculate the inter-carrier interference *** optimization objective is to maximize the system throughput under the constraint of a total transmitted power that is no greater than a certain *** order to reduce the computational complexity,a suboptimal solution to the optimization problem is obtained by a two-step ***,sub-carriers,antennas,and time slots are assigned to users under the assumption of equal power ***,the power allocation problem is solved according to the result of the first-step resource *** results show that the proposed multi-dimensional resource allocation strategy has a significant performance improvement in terms of system throughput compared with the existing one.
A new type hybrid automatic repeat request(HARQ) scheme based on orthogonal space-time block code(OSTBC) is proposed and evaluated in multiple-inputmultiple-output(mimo) *** transmit antennas are selected based on th...
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A new type hybrid automatic repeat request(HARQ) scheme based on orthogonal space-time block code(OSTBC) is proposed and evaluated in multiple-inputmultiple-output(mimo) *** transmit antennas are selected based on the feedback from the *** modulated symbols are encoded by spacetime block code(STBC) and obtained by space time code blocks which are suitable for the number of selected *** total packet error rate(PER) is given by defining the decoding function and the best value of the maximum number of HARQ retransmissions is *** and simulation results illustrate that:this new HARQ scheme with antenna selection method has lower PER and the result is also satisfying.
A transmit antenna selection(TAS)multi-input multi-output orthogonal frequency-division multiplexing(mimo-OFDM)system based on channel-orthogonalized space-frequency block coding(CO-SFBC)schemes was proposed for bette...
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A transmit antenna selection(TAS)multi-input multi-output orthogonal frequency-division multiplexing(mimo-OFDM)system based on channel-orthogonalized space-frequency block coding(CO-SFBC)schemes was proposed for better ***,the principles and criterions for designing CO-STBC/SFBC schemes with angle feedback were proposed,and then the effect of quantization for the feedback angle information within such schemes was ***,the TAS scheme was applied to the system to further improve the overall *** results show that the combination of the proposed CO-STBC and TAS schemes can significantly improve the system performance,which is much larger than only applying them to systems individually.
In this paper,considering the channel estimation error and the presence of co-channel interferences（CCIs）,we analyze the performance of multiuser multiple-inputmultiple-output wireless systems employing transmit be...
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In this paper,considering the channel estimation error and the presence of co-channel interferences（CCIs）,we analyze the performance of multiuser multiple-inputmultiple-output wireless systems employing transmit beamforming and maximum ratio combining（mimo MRC）.Exact closed-form cumulative distribution function expression of the signal-to-noise-plus-interference ratio（SINR）is ***,we present the average capacity of mimo MRC systems with multiuser *** results demonstrate the accuracy of our analytical expressions.
Space-time signal processing based on multiple-input multiple-output（mimo） systems is an active research field in which interfering signals are cancelled and multiuser detection is achieved using space diversity. In...
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Space-time signal processing based on multiple-input multiple-output（mimo） systems is an active research field in which interfering signals are cancelled and multiuser detection is achieved using space diversity. In a Rayleigh fading channel, space-time block cedes using multiple transmitting antennas can improve system performance and reduce bit-error-rate for multiuser detection. In this paper, several antenna configurations are designed for DS-CDMA communication in mimo systems. Space-time linear multinser detection and space-time serial interference cancellation multiuser detection are simulated. Bit-error-rate and computation complexities of the two methods are compared. Conclusions are given in the end.
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