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In this paper, a rectangular dielectric resonator antenna (RDRA) based on substrate integrated suspended line platform (SISL) is proposed for millimeter-wave applications. The dielectric resonator is embedded in the air cavity and fixed by the substrate 3. The cone feed line of the RDRA is presented in this design to excite the TEx1Δ1 (1 < Δ < 2) radiation mode. By using the SISL structure, the loss is reduced and a high gain is realized. Compared to the traditional DRA fed by microstrip line and coupling slot, the proposed design presents merits of low substrate lost, self-packaging and high efficiency. Simulated results show that the proposed RDRA obtained 10 dB impedance bandwidth of 11.41 % from 24.95 to 27.97 GHz. At 26.03 GHz, the simulated gain is 6.58 dBi.

In this paper, considering a multi-user pair and multi-untrusted relay two-way transmission network, a user pair-relay matching scheme is proposed. To maximize the achievable secrecy rate and reduce the complexity, we model the proposed matching problem as a bipartite graph and utilize the Kuhn-Munkres (KM) algorithm to find the maximum weighted complete matching. Furthermore, considering the fairness among the user pairs, we put a constraint on the minimum quality of service (QoS) requirements into the previous optimization problem. The existence of optimal matching is studied and the corresponding optimal solution is then presented after modifying the weight matrix. Simulation results finally validate that the proposed matching schemes can achieve improvement of average secrecy rate and harvest the diversity with more relays.

Viterbi algorithm is a commonly used algorithm for Gaussian filtered minimum frequency shift keying (GMSK) demodulation, but there exist some problems such as large delay, high overhead, and data overflow in the hardware implementation. Aiming at the problems of delay and overhead, we propose a novel update rule to optimize the stored transfer-state information table and realize one-step backtracking in this paper. It also ensures the realization of pipeline operation, reduces demodulation delay, and saves hardware resources. Furthermore, we adopt combinational logic to perform pre-decision, which not only satisfies the timing requirements, but also achieves the anti-overflow. The hardware implementation results demonstrate the feasibility and correctness of the design.

Metal-Organic Frameworks (MOFs) attract increasing attention in the field of energy storage, however, poor conductivity in most MOFs largely hinders their electrical properties. In this work, an effective strategy is developed to make the polyaniline (PANI) molecular chains grow in the pores of UiO-66 as one of the MOFs (labeled as PANI/UiO-66) to form a fixed interpenetrating network structure by using the highly stable porous MOFs, through a variety of synergistic effects to enhance the conductivity and electrochemical properties. Moreover, the design and analysis about PANI/UiO-66 is reported for the first time to our knowledge. In addition, PANI/UiO-66 exhibits an extraordinary capacitance of 1015 F g−1 at 1 A g−1 by electrochemical test. At the same time, the symmetric flexible solid-state supercapacitors is also assembled and tested. The resultant supercapacitor shows a favorable specific capacitance of 647 F g−1 at 1 A g−1 and a high cycling stability (91% capacitance retention after 5000 cycles). The bending test indicates that the obtained supercapacitor is flexible and its performance is only decreased 10% after 800 bending cycles with a bending angle of 180. This flexible solid-state supercapacitor shows great potential in energy storage device.