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Unitary (USTM) has got more attention for its potential in implementing high data rate transmission in a noncoherent multiple-antenna Rayleigh flat fading channel. In this paper, we have given out a bandwidth efficient turbo trellis-coded modulation scheme for the non-coherent multiple-antenna Rayleigh fading channel, where the channel state information (CSI) is not necessary both at the transmitter and the receiver. In this proposal, we combine USTM as constellations with the turbo trellis-coded modulation, resulting in the turbo trellis-coded USTM (TTC-USTM), with the trellis-coded USTM encoder as the component encoders. We have also applied the iterative maximum a posteriori (MAP) algorithm. According to PC simulations, we demonstrated that without bandwidth expansion, TTC-USTM produces obvious coding gains over its uncoded counterparts.

During numerical simulation of laser and tissue thermal interaction, the light fluence rate distribution should be formularized and constituted to the source term in the heat transfer equation. Usually the solution of light irradiative transport equation is given in extreme conditions such as full absorption (Lambert-Beer Law), full scattering (Lubelka-Munk theory), most scattering (Diffusion Approximation) et al. But in specific conditions, these solutions will induce different errors. The usually used Monte Carlo simulation (MCS) is more universal and exact but has difficulty to deal with dynamic parameter and fast simulation. Its area partition pattern has limits when applying FEM (finite element method) to solve the bio-heat transfer partial differential coefficient equation. Laser heat source plots of above methods showed much difference with MCS. In order to solve this problem, through analyzing different optical actions such as reflection, scattering and absorption on the laser induced heat generation in bio-tissue, a new attempt was made out which combined the modified beam broaden model and the diffusion approximation model. First the scattering coefficient was replaced by reduced scattering coefficient in the beam broaden model, which is more reasonable when scattering was treated as anisotropic scattering. Secondly the attenuation coefficient was replaced by effective attenuation coefficient in scattering dominating turbid bio-tissue. The computation results of the modified method were compared with Monte Carlo simulation and showed the model provided reasonable predictions of heat source term distribution than past methods. Such a research is useful for explaining the physical characteristics of heat source in the heat transfer equation, establishing effective photo-thermal model, and providing theory contrast for related laser medicine experiments.

Technology for fluorescence spectral imaging of microscopic has made significant strides advantages in the past several years. These advances have led to the enhanced choice of suitable diagnosis bases. Of course, fluorescence imaging can facilitate the study of disease at the molecular level in vivo. And this type of optical imaging has enabled real-time research to track cell movement, cell growth and other cell functions. With the addition of spectral imaging, fluorescence spectral imaging could complete a so-called 4-dimension imaging for the object. The investigator can obtain either the color imaging information or the information beyond it. The combination of both of them could show the relative completeness message. For evolution of software tools to deal with the resulting high-dimensionality datasets, it is necessary to find some effective and comparative reliable datasets analytical methods. In this paper, it also describes some quantitative fluorescence in tissue and addresses further applications of fluorescence spectral imaging. It includes MSE (Minimum Squared Error), PCA (Principal Components Analysis), ICA (Independent Component Analysis), FEA (Finite-Element Analysis), wavelet theory and their applications. They are useful in intact animals for disease detection, screening, diagnosis, treatment evaluation and drug development.

The obstacle of limb movement caused by brain hurtfuled disease is the patients' most encountered symptom. At present the general measurement and evaluation method is for monitoring the obstacle degree of patient's limb function, which depends on doctor's personal experience and his/hers subjective judgement, that is a visual and subjective method; it is not only fuzzy (non-quantitative) but also non-standardised. In this article a novel approach for the objective and quantitative measurement and evaluation with modern computerized imaging technique is reported. A new marking and grading method for obstacle degrees of limb movement is presented, and a practical computerized imaging system for measuring and evaluation is developed, which has been proved to be effective.

An optical fiber sensing system for biomedical and biochemical sensing was developed. The system was designed for multiparameter sensing to pH, SO2, NH3/NH4+. In the developed system, two light emitting diodes are used as light sources, a silicon photo-diode is used as light signal detector, a multimold stepped bifurcate optical fiber bundle with great aperture is used as light transmissive medium, the dyestuff is coupled to fiber by different methods. The new design idea is double beam compensation. The system is small, cheap but stable and sensitive, its response for pH is about 0.01 pH, the detective limits are 2 micrometers ol/L for NH+4 in water, 2 X 10-4 mol/L for SO32- in water, respectively. The system is powered with battery, so can be used for fieldwork.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.