Joint Singular Value Decomposition Research Articles

領域分割のための結合特異値分解による多重画像からの部分画像の選択

領域分割のための結合特異値分解による多重画像からの部分画像の選択

Performance of Dual-Polarized MIMO for TD-HSPA Evolution Systems

As the migration from code division multiple access (CDMA) to orthogonal frequency-division multiple access (OFDMA) involves a technological revolution in physical layer, the high speed packet access (HSPA) evolution (HSPA+) has been proposed for a smooth migration. HSPA+ is an effort to further improve radio performance of HSPA, and wideband CDMA (WCDMA) HSPA+ and time division-synchronous CDMA (TD-SCDMA) HSPA+ (TD-HSPA+) are two HSPA+ systems evolving from WCDMA and TD-SCDMA, respectively. Different from WCDMA HSPA+ system, TD-HSPA+ system utilizes eight antennas at Node B and two antennas at user equipment (UE) for 8 x 2 Multi-Input and Multi-Output (MIMO) transmission to achieve antenna array gain and diversity gain. Furthermore, to facilitate 8 x 2 MIMO configuration, the antenna elements are partitioned into two groups for dual-polarization transmissions. This paper focuses on 8 x 2 MIMO schemes in TD-HSPA+ systems, including the traditional single polarized MIMO (SP-MIMO), the separated and the joint singular value decomposition (SVD) based precoding dual-polarized MIMO (DP-MIMO) schemes. Performances of these TD-HSPA+ MIMO schemes are evaluated for both urban macro and micro scenarios. The simulation results show that the separated SVD based precoding DP-MIMO scheme performs better than the joint SVD based precoding DP-MIMO scheme, and the DP-MIMO scheme offers almost the same performance as the SP-MIMO due to the beamforming diversity gain and multiplex gain in TD-HSPA+ systems.

Patterns of co-variability between physical and biological parameters in the Arabian Sea

The relationship between physical forcing and biological response observed in the Arabian Sea for the years 1978–1986 were examined. Spatial and temporal patterns of variability in a climatological time-series of three possible physical forcing parameters and CZCS-derived phytoplankton pigment concentration during the annual cycle were quantified using single and joint empirical orthogonal function (EOF) and singular-value decomposition (SVD) analyses. Monthly composites of the NASA regional pigment data were interpolated to fill data voids and binned corresponding to the physical flux data. Nearly all the spatial-temporal analyses consistently partitioned a large portion of the variability using only 1 or 2 dominant modes and indicated a lag in the timing of the peak pigment concentration behind the maxima in physical forcing. In all cases, major modes of variability resembled the Southwest Monsoon pattern, with the Northeast Monsoon contributing very little to the total variance and covariance. The Joint EOF and SVD analyses incorporated subtle features surrounding the peak Southwest Monsoon phenomena. Correlation maps of the joint EOF analysis depicted differences in spatial variability of pigment concentration associated with stress and curl, showing areas of curl-driven upwelling distinct from coastal upwelling, with possible off-shore advection of the curl-induced high pigment waters.