For increasing the cross-track resolution, the multiple input multiple output (MIMO) technique is introduced into the swath bathymetry system and a new swath bathymetry approach using MIMO sonar is proposed. The MIM...For increasing the cross-track resolution, the multiple input multiple output (MIMO) technique is introduced into the swath bathymetry system and a new swath bathymetry approach using MIMO sonar is proposed. The MIMO sonar is composed of two parallel transmitting uniform linear arrays (ULAs) and a receiving ULA which is perpendicular to the former. The spacing between the two transmitting ULAs is equal to the product of the receiving sensor number and the receiving inter-sensor spacing. Furthermore, two narrowband linear frequency modulation (LFM) pulses, sharing the same frequency band but with opposite modulation slopes, are used as transmitting waveforms of the two transmitting ULAs. With such an array layout and transmitting signals, the MIMO sonar can sound a swath with the cross-track resolution doubling that of the traditional multibeam sonar using a Mills cross array. Numerical examples are provided to verify the effectiveness of the proposed approach.展开更多
An accurate, complete and realistic channel model is re- quired to accurately analyze the system performance of a multiple input multiple output (MIMO) broadband satellite mobile commu- nication system with dual-ort...An accurate, complete and realistic channel model is re- quired to accurately analyze the system performance of a multiple input multiple output (MIMO) broadband satellite mobile commu- nication system with dual-orthogonal polarized antennas (DPAs). In most current studies, the channel characteristic matrix (CCM) is always formed by an independent identical distribution (i.i.d) model of Rayleigh or Rice distribution and nevertheless incomplete and inaccurate to describe a broadband dual-orthogonal polarized MIMO land mobile satellite (BDM-LMS) channel. This paper fo- cuses on establishing the BDM-LMS channel statistical model, which combines the 4-state broadband LMS channel model, the time selective fading features, the channel covariance information (CCI) channel model and polarization correlations between an- tennas. The modeling steps of the channel model are introduced. The main emphasis is placed on the effects of the factors, such as antenna numbers, temporal correlations, terminal environments, elevation angles and polarization correlations between the DPAs, on the channel capacity in the BDM-LMS system. Many simulation results are provided to illustrate the effects of these factors through comparisons of the transmit rate, ergodic capacity and outage capacity with different factor values. Besides, the MIMO outage capacity advantages, which indicate the benefits of MIMO com- pared with a single input single output (SISO) system under the same channel condition, are also studied under i.i.d or BDM-LMS channel.展开更多
基金supported by the National Natural Science Foundation of China(11104222)the Doctorate Foundation of Northwestern Polytechnical University(CX201101)
文摘For increasing the cross-track resolution, the multiple input multiple output (MIMO) technique is introduced into the swath bathymetry system and a new swath bathymetry approach using MIMO sonar is proposed. The MIMO sonar is composed of two parallel transmitting uniform linear arrays (ULAs) and a receiving ULA which is perpendicular to the former. The spacing between the two transmitting ULAs is equal to the product of the receiving sensor number and the receiving inter-sensor spacing. Furthermore, two narrowband linear frequency modulation (LFM) pulses, sharing the same frequency band but with opposite modulation slopes, are used as transmitting waveforms of the two transmitting ULAs. With such an array layout and transmitting signals, the MIMO sonar can sound a swath with the cross-track resolution doubling that of the traditional multibeam sonar using a Mills cross array. Numerical examples are provided to verify the effectiveness of the proposed approach.
基金supported by the National Natural Science Foundation of China(61301105)the China Postdoctoral Science Foundation Funded Project(2013M531351)
文摘An accurate, complete and realistic channel model is re- quired to accurately analyze the system performance of a multiple input multiple output (MIMO) broadband satellite mobile commu- nication system with dual-orthogonal polarized antennas (DPAs). In most current studies, the channel characteristic matrix (CCM) is always formed by an independent identical distribution (i.i.d) model of Rayleigh or Rice distribution and nevertheless incomplete and inaccurate to describe a broadband dual-orthogonal polarized MIMO land mobile satellite (BDM-LMS) channel. This paper fo- cuses on establishing the BDM-LMS channel statistical model, which combines the 4-state broadband LMS channel model, the time selective fading features, the channel covariance information (CCI) channel model and polarization correlations between an- tennas. The modeling steps of the channel model are introduced. The main emphasis is placed on the effects of the factors, such as antenna numbers, temporal correlations, terminal environments, elevation angles and polarization correlations between the DPAs, on the channel capacity in the BDM-LMS system. Many simulation results are provided to illustrate the effects of these factors through comparisons of the transmit rate, ergodic capacity and outage capacity with different factor values. Besides, the MIMO outage capacity advantages, which indicate the benefits of MIMO com- pared with a single input single output (SISO) system under the same channel condition, are also studied under i.i.d or BDM-LMS channel.