In the literatures about Ultra Wide Band （UWB） to date, the receiver structure is mainly based on Rake receiver. But due to the wave distortion caused by overlapped between the received and the sent pulses, a lot of...In the literatures about Ultra Wide Band （UWB） to date, the receiver structure is mainly based on Rake receiver. But due to the wave distortion caused by overlapped between the received and the sent pulses, a lot of energy in demodulator will be lost. In this paper, a new receiver is developed by adopting maximum likelihood algorithm, in which RAKE structure is not needed and can also be implemented easily. The simulation showed that this method has BER advantage over the traditional RAKE receiver with maximal ratio combining at high SNR, and over the autocorrelation receiver as well.展开更多
In this paper, a cluster-based virtual multiple-input multiple-output （MIMO） transmission architecture is proposed for energy-constrained wireless sensor networks. In the proposed architecture, instead of using clus...In this paper, a cluster-based virtual multiple-input multiple-output （MIMO） transmission architecture is proposed for energy-constrained wireless sensor networks. In the proposed architecture, instead of using cluster members as cooperative nodes, multiple cluster heads cooperate to form virtual antenna array so that MIMO transmission can be implemented. According to the MIMO techniques used in this architecture, two different schemes, vertical Bell Laboratories layered space-time （V-BLAST） based cluster heads cooperative transmission （VCHCT） and space time block code （STBC） based cluster heads cooperative transmission （SCHCT）, are developed. Based on the communication energy consumption model, theoverall energy consumption model for both VCHCT and SCHCT are derived. Detailed comparison between these two schemes and the original low-energy adaptive clustering hierarchy （LEACH） is performed to investigate the performance of these two schemes. Simulation results not only verify the theoretical analysis but also show that the two schemes have their specific application scenarios. When the sink is far from the sensor area, SCHCT scheme is much more energy efficient than LEACH and VCHCT scheme even if it consumes additional inter-cluster communication energy. When the distance to sink is near the sensor area, VCHCT is preferable.展开更多
基金This work is supported by National "863" High Technology Project (2003AA12331004) , and National Nature Scientific Fundation of China(60472070) .
文摘In the literatures about Ultra Wide Band （UWB） to date, the receiver structure is mainly based on Rake receiver. But due to the wave distortion caused by overlapped between the received and the sent pulses, a lot of energy in demodulator will be lost. In this paper, a new receiver is developed by adopting maximum likelihood algorithm, in which RAKE structure is not needed and can also be implemented easily. The simulation showed that this method has BER advantage over the traditional RAKE receiver with maximal ratio combining at high SNR, and over the autocorrelation receiver as well.
基金supported by the National Natural Science Foundation of China (60871042, 60872049, 60971082, and 60972073)National Great Science Specific Project (2009ZX03003-001,2009ZX03003-011)
文摘In this paper, a cluster-based virtual multiple-input multiple-output （MIMO） transmission architecture is proposed for energy-constrained wireless sensor networks. In the proposed architecture, instead of using cluster members as cooperative nodes, multiple cluster heads cooperate to form virtual antenna array so that MIMO transmission can be implemented. According to the MIMO techniques used in this architecture, two different schemes, vertical Bell Laboratories layered space-time （V-BLAST） based cluster heads cooperative transmission （VCHCT） and space time block code （STBC） based cluster heads cooperative transmission （SCHCT）, are developed. Based on the communication energy consumption model, theoverall energy consumption model for both VCHCT and SCHCT are derived. Detailed comparison between these two schemes and the original low-energy adaptive clustering hierarchy （LEACH） is performed to investigate the performance of these two schemes. Simulation results not only verify the theoretical analysis but also show that the two schemes have their specific application scenarios. When the sink is far from the sensor area, SCHCT scheme is much more energy efficient than LEACH and VCHCT scheme even if it consumes additional inter-cluster communication energy. When the distance to sink is near the sensor area, VCHCT is preferable.
