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Polarization information can greatly improve the ability of detection, parameter retrieval, and classification for entomological radar. In recent, the instantaneous fully polarimetric measurement technique is used in entomological radar, so as to relax the restriction of invariant orientation during observation compared to the typical vertical-looking radar with linear-polarized rotation configuration. However, the fully polarimetric measurement is based on a multichannels’ radar system, and the imbalance and crosstalk between channels, namely, polarimetric errors, will severely affect the measurement of the polarimetric scattering matrix (PSM). Thus, polarimetric calibration is essential to obtain the accurate polarization information of targets. In contrast to inefficient and manual calibration methods, a data-driven polarimetric calibration method is proposed based on the assumption of reciprocity and bilateral symmetry of insects in this article. The polarimetric errors are elaborately decomposed into two components, which could be estimated by reciprocity and bilateral symmetry, respectively. In addition, because the proposed method is data-driven, the calibration process could be automatically executed to compensate for the temporal-variant polarimetric errors induced by temperature change and, thus, suitable for the long-term operation of entomological radar. Simulations and experiments are carried out to evaluate the performance of the proposed calibration method. Results show that it could achieve high accuracy when the number of insects used as calibrators is large enough. The proposed method has been applied in Ku-band high-resolution fully polarimetric entomological radars for cross-border migratory insect observation in Yunnan province, China. [ABSTRACT FROM AUTHOR]

Besides mosquitoes, ticks are regarded as the primary source of vector-borne infectious diseases. Indeed, a wide variety of severe infectious human diseases, including those involving viruses, are transmitted by ticks in many parts of the world. To date, there are no published reports on the use of next-generation sequencing for studying viral diversity in ticks or discovering new viruses in these arthropods from China. Here, Ion-torrent sequencing was used to investigate the presence of viruses in three Rhipicephalus spp. tick pools (NY-11, NY-13, and MM-13) collected from the Menglian district of Yunnan, China. The sequencing run resulted in 3,641,088, 3,106,733, and 3,871,851 reads in each tick pool after trimming. Reads and assembled contiguous sequences (contigs) were subject to basic local alignment search tool analysis against the GenBank database. Large numbers of reads and contigs related to known viral sequences corresponding to a broad range of viral families were identified. Some of the sequences originated from viruses that have not been described previously in ticks. Our findings will facilitate better understanding of the tick virome, and add to our current knowledge of disease-causing viruses in ticks living under natural conditions. [ABSTRACT FROM AUTHOR]