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In this study, aiming at fulfilling the requirement of polarization acquisition and utilization, a method for active deception jamming recognition based on the time-varying polarization-conversion metasurface is investigated. First, an anisotropic phase-modulated metasurface supporting 3-bit phase quantization in the 9.6～10.1 GHz frequency band is designed. By optimizing the periodical phase coding, the polarization state can be converted on demand. And then, loading the polarization-conversion metasurface on a single polarization radar antenna so that the polarization states of the antenna can change along a specific trajectory. By extracting the difference in the polarization domain between target and active deception jamming, the active deception jamming could be distinguished from the radar echo. The simulation results show that under the constraints of three different polarization trajectories, the active deception jamming and targets exhibit a significant clustering effect, and the identification effect is stable. Compared with jamming identification methods that rely on dual-polarization or full-polarization radar systems, the proposed method has both low cost and high efficiency, which has great application potential in radar anti-jamming.

In order to solve the severe damage and difficult support of lower group coal roadways under the influence of mining in upper group coal seams near Malan Mine, a field survey, numerical simulation, and theoretical analysis were conducted to analyze the stress environment of roadway surrounding rock during tunnel excavation and upper group coal mining. Based on this analysis, a strengthening support plan with combination structure of original plan and pipe cable was proposed, comparing the development of plastic zones and surrounding rock deformation between the original support plan and the strengthening support plan. The results showed that under the strengthening support plan, the vertical displacement and horizontal displacement of roadway surrounding rock reduced by 12.76%, 11.09%, and 17.06%, 16.63% respectively under tunnel excavation and mining influence, and the development of plastic zones was also significantly improved compared to the original support; the combination structure of pipe cable strengthening support plan has good supporting effect and can effectively control roadway surrounding rock development.

This paper proposes an adaptive filtering method called the Adaptive Moving spectral Depolarization Ratio (AMsDR) filter to mitigate the clutter for dual-polarization weather radar based on Jensen-Shannon divergence principle. Specifically, the spectral depolarization ratio in the range-Doppler domain is the main variable distinguishing precipitation from clutter. The AMsDR filter can remove the clutter and noise and retain precipitation based on the difference of the spectral polarization feature and the spectral continuity of precipitation and clutter. The AMsDR filter can adaptively select the filter threshold depending on the echo difference between precipitation and clutter in different azimuths. Thus, the performance of the proposed filter is better than that of the current methods.

To mitigate Radio Frequency Interference (RFI) for polarimetric Doppler weather radars, this paper proposes to use spectral polarimetric filters. Polarimetric weather radars can be divided into two basic categories: Simultaneously Transmitting and Simultaneously Receiving (STSR) and Alternately Transmitting and Simultaneously Receiving (ATSR). First, the real RFI measurements from an operational C-band STSR weather radar help characterize the temporal, spectral and polarimetric features of RFI. Then, RFI is simulated in an X-band ATSR radar to quantify the performances of spectral polarimetric filters. Overall, spectral polarimetric filters can keep the precipitation and remove RFI in an ATSR radar. Finally, the data division method is put forward for STSR radars by mimicking the ATSR measurements. Good performance in RFI mitigation is also verified by using the same spectral polarimetric filters.

Micromotion targets can enable microDoppler modulation on electromagnetic waves owing to their motion components in different directions, resulting in the defocusing effects of the target imaging features along the azimuth direction. This phenomenon has been widely considered and investigated in target recognition and antirecognition. As a research hotspot, electronically controlled time-varying electromagnetic materials have fast modulation characteristics; however, their imaging characteristics have not received much attention. This study investigates the Synthetic Aperture Radar (SAR) modulation characteristics along the range direction of electronically controlled time-varying electromagnetic materials. Then, this study establishes the time-varying electromagnetic material spectrum transformation model and analyzes the SAR target characteristic control principle. Taking the Phase-Switched Screen (PSS) as an example, a nonperiodic PSS phase modulation model is established, and its spectrum has continuous frequency shift characteristics. On this basis, the influence of continuous frequency shift modulation induced by nonperiodic PSS on SAR was further discussed and the defocusing phenomenon of the target along the range direction was detected. Through the simulation of measured data, the validity of the proposed theoretical method is verified.

The technical background of EM metamaterials was introduced, the development history and working mechanism of electrically controlled LC technology, the latest developments in the research and application of electrically controlled LC phased array antenna were illustrated.The electrically controlled LC phased array antenna’s advantages and disadvantages were summarized.Finally, the future prospect of LC metamaterials in the fi eld of EM metamaterials was expounded.

Independent processing of each polarization channel and three-dimensional multistage imaging ignore the correlation between data, resulting in the mismatch between scattering centers and the inaccurate acquisition of polarization scattering matrices. To address these issues, a full-polarization Synthetic Aperture Radar (SAR) joint multidimensional reconstruction method based on sparse reconstruction is proposed in this study. In this method, all polarization channels and dimensions are integrated by setting the joint sparse constraints, and the full-polarization SAR joint multidimensional reconstruction is modeled as a multichannel joint sparse reconstruction problem. After the model is simplified by data interpolation, an efficient model-solving method is proposed by combining the three-dimensional fast Fourier transform, conjugate gradient method, and Newton iteration method, where the polarization scattering matrix and three-dimensional information of the target can be obtained at the same time. The proposed method ensures that the sparse support sets of different polarization channels and dimensions are consistent and utilizes the additional information generated by the correlation between data. On the basis of the simulation and electromagnetic calculation data, the experimental results indicate that the proposed method is tolerant of noise and immune to the types of targets. Moreover, the proposed method can effectively obtain the multidimensional reconstruction results of the target, where both the resolution of the imaging results and the estimation accuracy of the polarization scattering matrix are high.

Synthetic Aperture Radar (SAR) is an all-weather and all-time imaging radar with high resolution, which is widely used for enemy reconnaissance to provide timely and accurate intelligence for taking decisions during wars. It has become a hot issue in the contemporary electronic warfare to suppress and disorder the reconnaissance imaging of SAR equipment for protecting high-value targets and important strategic areas. This study discusses the development and future trend of SAR jamming techniques. First, the history of development of SAR jamming techniques is discussed and explained in detail. Then, the advantages and disadvantages of the typical SAR jamming models are comparatively analyzed together with simulation experiments. Finally, the current defects of the SAR jamming techniques are summarized and the future trend of the SAR jamming techniques is also pointed out, providing some reference for experts and scholars.

Suppression position of the traditional noise convolution modulation Synthetic Aperture Radar (SAR) jamming lags behind in range and suppression area in azimuth is uncontrollable. Considering this defect, an enhanced jamming method is proposed herein. First, the frequency of the intercepted signal is shifted in fast-time to control the suppression position in range. Then, the convolution with the noise is implemented, which has been filtered in slow-time, to control the suppression area in azimuth. Theoretical analysis and simulation results demonstrate that the proposed jamming method can efficiently control the jamming position in range and suppression area when compared with the traditional noise convolution modulation jamming. Even if some reconnaissance errors exist, the local scenario can still be shielded effectively. Furthermore, the utilization efficiency of jamming energy is also improved under the same condition, which will provide some reference values and inputs for engineering applications.

Background and objective Flubendazole is an anthelmintic and categorized in benzimidazole. Previous evidence indicates its suppression on proliferation of colon cancer and breast cancer cells. Our study aims to explore the effects of flubendazole on non-small cell lung cancer A549 and H460 cell lines and the underlying mechanism. Methods CCK-8 assay was used to detect the effect of flubendazole at different concentrations on viability of both cell lines A549 and H460. We used western blot to detect the expression levels of autophagy-related proteins p62 and LC3 after flubendazole treatment. Cells were transfected with tandem fluorescent adenovirus (mRFP-GFP-LC3), and the impact of flubendazole treatment on autophagic flux were analyzed. Results Cell viability analysis showed a dose-dependent inhibitory effect on proliferation of both A549 and H460, comparing to cells without flubendazole treating (P