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The compressive strength prediction model of carbon fiber concrete is first introduced. Based on the limit equilibrium method and Hill-cabbage composite damage criterion, the calculation model of axial compression ultimate load capacity considering the fiber volume rate, GFRP tube thickness and fiber winding angle for GFRP confined carbon fiber concrete short column is proposed. According to the existing literature test results, the rationality of the calculation model is verified which shows the proposed calculation model of axial compression ultimate load capacity for GFRP confined fiber reinforced concrete short columns can satisfy the needs of engineering application very well.

In this paper, the problems such as negative power and scattering mechanism ambiguity in original polarimetric SAR three-component decomposition are introduced, and the remaining flaws in its improved approaches are in depth analyzed. Based on these, an adaptive three-component decomposition is proposed, and more generalized scattering models are used. Because in one pixel there may exist two odd or double bounce scattering targets with different orientation angels, the proposed method firstly considers this situation, so that the surface and double bounce scattering can be preserved more sufficiently. And then the alpha parameter is used to identify the dominant scattering except for the volume scattering. Lastly, an optimization measure to the pixels with negative power is proposed, which significantly decreases the negative power pixels count, so the decomposition will be more accurate and more valid. The results show great improvements in real scattering characteristics extraction and the flaws in model based decomposition approaches can be better resolved.

CE-1 Lunar Microwave Sounder (CELMS) is the first passive microwave radiometer in the world to sound the surface of the moon in the lunar orbit at altitude of 200 km. The scientific objective of CELMS is to obtain global brightness temperature (TB) of the moon, to retrieve information on lunar regolith, and to evaluate the distribution of helium-3 on the moon implanted by solar wind. Before launch of CELMS, a series of experiments were carried out in laboratories to test the performances of the systems, and to calibrate the responses between the input of TB and the output of voltage from the receivers. However, the thermal condition exposed to CELMS is more complicated in lunar orbit than on the Earth, which makes the temperatures of different parts of CELMS wave vary greatly, and the cosmic background is not very clean due to the pointing of cold space antenna to the direction of the satellite running, which brings uncertainties into data-processing of CELMS when the temperature of cold space is used as a calibrator. Furthermore, the lack of knowledge on the lunar ingredients and compositions, distributions of physical temperatures, and properties on lunar microwave radiation leads to difficulties in validating the measurements and retrievals of CELMS. By analyzing the results of ground experiments and the measurements of CELMS in-orbit, along with our knowledge of the properties of lunar surface, here we give algorithms on calibration and antenna pattern correction (APC) of CELMS. We also describe in detail the principle of microwave transfer among the elements of CELMS, and discuss the method on testing calibration parameters of the system. In addition, the theory and model on correction antenna pattern of CELMS are developed by comparing antenna temperatures by CELMS with those simulated by microwave radiative transfer models. The global distribution of TB is given and the features of TB are analyzed. Our results show rich information included in TB on the properties of lunar regolith, especially the thickness and dielectric constant, which are nearly directly reflected by the differences of TB at day and those at night.

Among many scientific objectives of lunar exploration, investigations on lunar soil become attractive due to the existence of He3 and ilmenite in the lunar soil and their possible utilization as nuclear fuel for power generation. Although the composition of the lunar surface soil can be determined by optical and γ/X-ray spectrometers, etc., the evaluation of the total reserves of He3 and ilmenite within the regolith and in the lunar interior are still not available. In this paper, we give a rough analysis of the microwave brightness temperature images of the lunar disc observed using the NRAO 12 meter Telescope and Siberian Solar Radio Telescope. We also present the results of the microwave dielectric properties of terrestrial analogues of lunar soil and, discuss some basic relations between the microwave brightness temperature and lunar soil properties.

China plans to implement its first lunar exploration mission Chang'E-1 by 2007. The mission objectives are

Fully polarimetric microwave radiometer is a new type of passive microwave sensor for measuring ocean wind vector. Digital correlation technology is used in it to get all the four Stokes parameters of ocean emission in this paper. Digital correlator is the main part of fully polarimetric radiometer. In the paper, design of a novel digital correlator is presented. Two high-speed, dual A/D converters are used to sample four signals, and the sampling results are operated in FPGA-Vertex5 to make both self- and cross-correlation calculations. The test results of the correlator are given. The four channels are sampled at 360 MHz. For both 100 MHz and 150 MHz input, the correlation coefficient between the measurements and their ideal results is above 0.9999999. The whole power of digital correlator is 11.3 W.

The 3D imaging microwave altimeter is a proposed instrument for obtaining centimeter level accuracy of topography for ocean and meter-level accuracy of topography for land. In order to ensure the normal operation of the system and improve its performance, the EMI and EMC problems should be considered in design phase. In this paper, the architecture of altimeter system is shown and the main EMI sources in the system are pointed out. According to the characters of EMI sources, EMC design for RF circuit and some key components including TWTA, high-speed AD converter and ICs is outlined.

Carrier lock detection function based on QPSK digital receiver has been analyzed in details. Beginning with how to construct a carrier lock detector, we point out the conditions that a good carrier lock detection function should conform to. Then a new carrier lock detector was proposed, which surpasses the traditional methods in performance and hardware cost. By comparing the performances of all of these carrier lock detectors, we conclude that the new carrier lock detector has the better performance at lower SNR, which indicate it is more suitable for lower demodulator threshold digital receivers.