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Airborne system is developing towards the direction of integration, intelligence and automation. The integration of the system is usually realized by the way of cross-linking of the system. The cross-linking relationship among systems is complex, and the number of cables is large, which can increase the complexity of the whole airborne system. Requirements for hardware resources of the airborne system are very high, and the contradiction between the high demand for the integrated airborne system and the slow upgrade speed of hardware resources appears. The demands for intelligent airborne systems are also developed. A distributed cloud-edge-terminal intelligent architecture for airborne system is proposed, which combines cloud-edge-terminal technology, distributed network control technology and distributed integrated modular avionics system technology. The architecture is reasonably constructed through cloud management platform, edge control platform and terminal platform, and is configured with high-speed secure real-time network and container software technology. The architecture proposed in this paper can increase the degree of integration of the multi-aircraft airborne system while without increasing the whole aircraft complexity. The architecture can meet the requirement of the new technologies application such as artificial intelligence, information fusion, large data processing, and the expansion of new functions.

In this article, a newly spoof surface plasmon polaritons (SSPPs) is proposed and used to design a compact wideband bandpass filter (BPF). Different from the traditional SSPP unit cell with one-shaped structure, the unit cell of the proposed SSPPs consists of an H-shaped slotline and a bilateral T-shaped slotline. Benefiting from the hybrid structure, no transition portion is needed for impedance matching in the design of the microwave filter, which highly reduces the horizontal size of the SSPPs-based filter. The transition structure of microstrip to slotline provides a capacitance with a highpass frequency response, which enables the realization of a passband by cooperating with the natural lowpass property of SSPPs. Also, the upper and lower cutoff frequencies of the proposed filter can be adjusted independently by the key parameters. Besides, a wide upper stopband can be obtained by properly designing the SSPPs unit cell and the microstrip to slotline structure. Finally, a well-designed BPF operated at 1.3–6.2 GHz and its upper stopband rejection reaching 20 GHz is fabricated and measured. The test results are in good agreement with the simulations, which verifies the feasibility of the proposed structure and design method. [ABSTRACT FROM AUTHOR]

In this letter, a novel dual‐band bandpass filter (BPF) with independently controllable center frequencies, bandwidths, and transmission zeros (TZs) is presented. The proposed BPF is realized by using eighth‐mode substrate‐integrated circular cavities (EMSICCs) and coplanar waveguide (CPW) resonators. The CPW resonators are embedded in the upper surface of the EMSICCs, allowing for a compact size without additional circuit dimensions. Finally, a dual‐band BPF for WLAN is designed and fabricated with center frequencies of 2.45 and 5.2 GHz. The measured results closely align with the simulated ones, validating the performance of the filter. Multiple TZs are generated by cross‐coupling and source‐load coupling, which results in good out‐of‐band rejection performance. [ABSTRACT FROM AUTHOR]

Quasi‐reflectionless balanced bandpass filters (BPFs) using absorption network for common‐mode (CM) rejection and stopband extension are proposed and demonstrated. First, a quasi‐reflectionless balanced BPF is constructed by using absorption network and a uniform impedance resonator (UIR), where absorption network consists of lossy stubs loaded at both the input/output port and the ends of the coupling line (CLs). Owning to the resonating of absorption network, a three‐pole balanced BPF with CM and differential‐mode (DM) reflectionless performance are realized. Meanwhile, harmonic of DM is suppressed by exploring the loading position of the resistor. Second, to improve the selectivity of the filter, two open stubs are symmetrically loaded to the center of the UIR, a five‐pole quasi‐reflectionless balanced BPF with two transmission zeros are presented. Both proposed quasi‐reflectionless balanced BPFs are fabricated and measured. The measured results are in good agreement with the simulated ones, verifying the proposed design concept. [ABSTRACT FROM AUTHOR]

Population size is a critical indicator used to assess the demographic profile and conservation status of animal species living in disturbed habitats. Using GIS technology, we calculated the remaining habitat area and estimated the population size of the Guizhou snub-nosed monkey (Rhinopithecus brelichi), an Endangered primate endemic to China. The last remaining population of this species resides in the Fanjingshan National Nature Reserve (FNNR). We combined data on forest cover and patterns of group movement to estimate the size and continuity of their habitat. The results indicated that the area of remaining suitable habitat is 69.6 km2. However the monkeys are confined to an area of only 27.8 km2 (6.6% of the total reserve area of 419 km2) located in the northern part of the reserve. The remaining 28.5 km2 of suitable habitat is located in the southern part of the reserve and inaccessible to the monkeys because of the recent construction of an aerial tram. Based on estimates of population density, we calculated that the remaining world’s population of R. brelichi is approximately 125–336 individuals. In order to protect this species from extinction, we recommend that the highly fragmented evergreen and deciduous broadleaf mixed forest adjacent to the remaining troop’s home range be given protected status and an active program of forest regeneration in this area be implemented immediately.