Coordinated multi-point (CoMP) transmission is put forward in the long term evolution-advanced (LTE-A) system to improve both average and cell-edge throughput. CoMP-joint pro- cessing (JP) scheme can get a large...Coordinated multi-point (CoMP) transmission is put forward in the long term evolution-advanced (LTE-A) system to improve both average and cell-edge throughput. CoMP-joint pro- cessing (JP) scheme can get a larger cell-edge throughput and a lower bit error rate (BER) than the CoMP-coordinated beamform- ing (CB) scheme, but it also has higher complexity due to data sharing. A hybrid coordinated strategy with parameter c~, which indicates the proportion of users employing the CoMP-JP scheme, is proposed to apply the CoMP-JP scheme to improve the poorer communication quality of cell edge and employ the CoMP-CB scheme for other users to enhance average throughput and spec- tral efficiency. This paradigm selects users defined by the certain threshold of signal to interference plus noise power ratio (SINR) corresponding to the parameter a to the CoMP-JP scheme. This paper compares the BER performance between the block diag- onalization (BD) based precoding and the linear precoders by maximizing signal to leakage and noise ratio (SLNR), and also in- dicates that the SLNR based precoding algorithm gets lower BER than the BD based precoding algorithm with certain signal-to-noise ratios (SNRs). Finally, this paper discusses that the system perfor- mance is partially affected by the percentage of CoMP-JP users and concludes that 50% of users sorted to communicate under the CoMP-JP scheme will reach the best system performance.展开更多
Coordinated multi-point (CoMP) joint transmission is considered in the 3rd generation partnership project (3GPP) long term evolution (LTE)-advanced as a key technique to mitigate inter-cell interference and impr...Coordinated multi-point (CoMP) joint transmission is considered in the 3rd generation partnership project (3GPP) long term evolution (LTE)-advanced as a key technique to mitigate inter-cell interference and improve the cell-edge performance. To effectively apply CoMP joint transmission,efficient frequency reuse schemes need to be designed to support resource management cooperation among coordinated cells. However,most of the existing frequency reuse schemes are not suitable for CoMP systems due to not considering multi-point joint transmission scenarios in their frequency reuse rules. In addition,the restrictions of frequency resources in those schemes result in a high blocking probability. To solve the above two problems,a multi-beam cooperative frequency reuse (MBCFR) scheme is proposed in this paper,which reuses all the available frequency resources in each sector and supports multi-beam joint transmission for cell-edge users. Besides,the blocking probability is proved to be efficiently reduced. Moreover,a frequency-segment-sequence based MBCFR scheme is introduced to further reduce the inter-cell interference. System level simulations demonstrate that the proposed scheme results in higher cell-edge average throughput and cell-average throughput with lower blocking probability.展开更多
Coordinated multipoint(CoM P)transmission and reception is a technique to reduce intercell interference and increase the cell edge throughput.In order to get maximum CoM P gain the networks and terminals involved in C...Coordinated multipoint(CoM P)transmission and reception is a technique to reduce intercell interference and increase the cell edge throughput.In order to get maximum CoM P gain the networks and terminals involved in CoM P communication should be robust against time and frequency offset due to asynchronism between terminals and base stations.However,the modulation techniques proposed in LTE-Advanced standard(SC-FDMA and OFDMA)are quite sensitive to frequency offset because of DFT/IDFT used in the modulation systems,which brings difficulties for commercial implementation of CoM P technique based on LTE-Advanced.To relax the synchronization requirement in CoM P system,in this paper we introduce a CoM P technique based on a new multicarrier modulation scheme-multicarrier time division multiple access(MC-TDMA).In comparison with SC-FDMA and OFDMA,the MC-TDMA modulation can significantly improve the CoM P performance in case of carrier frequency offset.Simulation shows that at 20%of carrier frequency offset the CoM P system with MC-TDMA modulation can also keep high performance,while the system with SC-FDMA and OFDMA is totally lost in work.展开更多
在协作多点传输(coordinated multiple points transmission,CoMP)系统中,为了提高小区边缘用户传输速率和系统总吞吐量,提出了一种联合天线选择和功率分配的优化算法。在基于信道容量增量的天线选择策略(antenraselection lased on cap...在协作多点传输(coordinated multiple points transmission,CoMP)系统中,为了提高小区边缘用户传输速率和系统总吞吐量,提出了一种联合天线选择和功率分配的优化算法。在基于信道容量增量的天线选择策略(antenraselection lased on capacity increment,CIAS)中,推导了当用户端采用最大比合并时用户信道容量的表达式,并根据所设定的信道容量增量选择出所有满足条件的天线;在最优功率分配算法(optimal power allocation,OPA)中,推导了协作多点多用户系统中用户传输速率的表达式,在总功率受限的情况下通过采用优化的迭代功率分配算法,得到了最优的功率分配。理论分析和仿真结果表明,与等功率分配策略(equal power allocation,EPA)和功率与信道增益成正比的功率分配策略(proportion to channel gain,PCG)相比,联合了天线选择和功率分配的算法不仅能最大提升对边缘用户的传输速率,而且能更好地提高系统的信道容量。展开更多
基金supported by the National Science and Technology Major Project of China(2013ZX03001024-003)
文摘Coordinated multi-point (CoMP) transmission is put forward in the long term evolution-advanced (LTE-A) system to improve both average and cell-edge throughput. CoMP-joint pro- cessing (JP) scheme can get a larger cell-edge throughput and a lower bit error rate (BER) than the CoMP-coordinated beamform- ing (CB) scheme, but it also has higher complexity due to data sharing. A hybrid coordinated strategy with parameter c~, which indicates the proportion of users employing the CoMP-JP scheme, is proposed to apply the CoMP-JP scheme to improve the poorer communication quality of cell edge and employ the CoMP-CB scheme for other users to enhance average throughput and spec- tral efficiency. This paradigm selects users defined by the certain threshold of signal to interference plus noise power ratio (SINR) corresponding to the parameter a to the CoMP-JP scheme. This paper compares the BER performance between the block diag- onalization (BD) based precoding and the linear precoders by maximizing signal to leakage and noise ratio (SLNR), and also in- dicates that the SLNR based precoding algorithm gets lower BER than the BD based precoding algorithm with certain signal-to-noise ratios (SNRs). Finally, this paper discusses that the system perfor- mance is partially affected by the percentage of CoMP-JP users and concludes that 50% of users sorted to communicate under the CoMP-JP scheme will reach the best system performance.
基金supported by the Sino-Swedish Project(2008DFA12110)the Key Project of BMSTC (D08080100620802)+1 种基金the National Natural Science Foundation of China (60872048)the National Science and Technology Special Project ‘Group Cell’ ( 2009ZX03003-011)
文摘Coordinated multi-point (CoMP) joint transmission is considered in the 3rd generation partnership project (3GPP) long term evolution (LTE)-advanced as a key technique to mitigate inter-cell interference and improve the cell-edge performance. To effectively apply CoMP joint transmission,efficient frequency reuse schemes need to be designed to support resource management cooperation among coordinated cells. However,most of the existing frequency reuse schemes are not suitable for CoMP systems due to not considering multi-point joint transmission scenarios in their frequency reuse rules. In addition,the restrictions of frequency resources in those schemes result in a high blocking probability. To solve the above two problems,a multi-beam cooperative frequency reuse (MBCFR) scheme is proposed in this paper,which reuses all the available frequency resources in each sector and supports multi-beam joint transmission for cell-edge users. Besides,the blocking probability is proved to be efficiently reduced. Moreover,a frequency-segment-sequence based MBCFR scheme is introduced to further reduce the inter-cell interference. System level simulations demonstrate that the proposed scheme results in higher cell-edge average throughput and cell-average throughput with lower blocking probability.
文摘Coordinated multipoint(CoM P)transmission and reception is a technique to reduce intercell interference and increase the cell edge throughput.In order to get maximum CoM P gain the networks and terminals involved in CoM P communication should be robust against time and frequency offset due to asynchronism between terminals and base stations.However,the modulation techniques proposed in LTE-Advanced standard(SC-FDMA and OFDMA)are quite sensitive to frequency offset because of DFT/IDFT used in the modulation systems,which brings difficulties for commercial implementation of CoM P technique based on LTE-Advanced.To relax the synchronization requirement in CoM P system,in this paper we introduce a CoM P technique based on a new multicarrier modulation scheme-multicarrier time division multiple access(MC-TDMA).In comparison with SC-FDMA and OFDMA,the MC-TDMA modulation can significantly improve the CoM P performance in case of carrier frequency offset.Simulation shows that at 20%of carrier frequency offset the CoM P system with MC-TDMA modulation can also keep high performance,while the system with SC-FDMA and OFDMA is totally lost in work.
文摘在协作多点传输(coordinated multiple points transmission,CoMP)系统中,为了提高小区边缘用户传输速率和系统总吞吐量,提出了一种联合天线选择和功率分配的优化算法。在基于信道容量增量的天线选择策略(antenraselection lased on capacity increment,CIAS)中,推导了当用户端采用最大比合并时用户信道容量的表达式,并根据所设定的信道容量增量选择出所有满足条件的天线;在最优功率分配算法(optimal power allocation,OPA)中,推导了协作多点多用户系统中用户传输速率的表达式,在总功率受限的情况下通过采用优化的迭代功率分配算法,得到了最优的功率分配。理论分析和仿真结果表明,与等功率分配策略(equal power allocation,EPA)和功率与信道增益成正比的功率分配策略(proportion to channel gain,PCG)相比,联合了天线选择和功率分配的算法不仅能最大提升对边缘用户的传输速率,而且能更好地提高系统的信道容量。