Nonlinear optical CsB3O5 single crystals have been grown successfully using NaF as a flux. The primary CsB3O5-NaF quasi-binary system has been investigated by X-ray diffraction and differential thermal analysis. There...Nonlinear optical CsB3O5 single crystals have been grown successfully using NaF as a flux. The primary CsB3O5-NaF quasi-binary system has been investigated by X-ray diffraction and differential thermal analysis. There is a single eutectic point, and the eutectic composition corresponds to 40mol% NaF with the temperature of 690.5 ℃ in CsB3O5-NaF system. Volatility of the CsB3O5-NaF system along the liquidus has been measured, and the volatiles of the solution were collected and detected by XRD method. Growth of CsB3O5 crystals was carried out by different composition of NaF in CsB3O5-NaF system, and the growth parameters were discussed. Simultaneously, the properties of grown crystals from NaF flux were characterized by transmission spectrum and scanning electron microscopy.展开更多
This paper studies the adaptive beamforming algorithm based on the frequency diverse array(FDA)array where the interference is located at the same angle(but different range)with the target.We take the cross subarray-b...This paper studies the adaptive beamforming algorithm based on the frequency diverse array(FDA)array where the interference is located at the same angle(but different range)with the target.We take the cross subarray-based FDA with sinusoidal frequency offset(CSB sin-FDA)as the receiving array instead of the basic FDA.The sampling covariance matrix under insufficient snapshot can be corrected by the automatic diagonal loading method.On the basis of decomposing the mismatched steering vector error into a vertical component and a parallel one,this paper searches the vertical component of the error by the quadratic constraint method.The numerical simulation verifies that the beamformer based on the CSB sin-FDA can effectively hold the mainlobe at the target position when the snapshot is insufficient or the steering vector is mismatched.展开更多
基金This work was financially supported by the National Natural Science Foundation of China (No. 60378026)
文摘Nonlinear optical CsB3O5 single crystals have been grown successfully using NaF as a flux. The primary CsB3O5-NaF quasi-binary system has been investigated by X-ray diffraction and differential thermal analysis. There is a single eutectic point, and the eutectic composition corresponds to 40mol% NaF with the temperature of 690.5 ℃ in CsB3O5-NaF system. Volatility of the CsB3O5-NaF system along the liquidus has been measured, and the volatiles of the solution were collected and detected by XRD method. Growth of CsB3O5 crystals was carried out by different composition of NaF in CsB3O5-NaF system, and the growth parameters were discussed. Simultaneously, the properties of grown crystals from NaF flux were characterized by transmission spectrum and scanning electron microscopy.
基金supported by the National Natural Science Foundation of China(61503408)
文摘This paper studies the adaptive beamforming algorithm based on the frequency diverse array(FDA)array where the interference is located at the same angle(but different range)with the target.We take the cross subarray-based FDA with sinusoidal frequency offset(CSB sin-FDA)as the receiving array instead of the basic FDA.The sampling covariance matrix under insufficient snapshot can be corrected by the automatic diagonal loading method.On the basis of decomposing the mismatched steering vector error into a vertical component and a parallel one,this paper searches the vertical component of the error by the quadratic constraint method.The numerical simulation verifies that the beamformer based on the CSB sin-FDA can effectively hold the mainlobe at the target position when the snapshot is insufficient or the steering vector is mismatched.