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A new microstrip tri‐band filtering power divider (FPD) with favourable filtering and isolation performance based on the tri‐mode fork‐type resonator is presented in this study. By constructing the coupling scheme between the input transmission line and two pairs of symmetric fork‐type resonators, a nice tri‐passband filtering power division response can be easily achieved without an additional matching network. Meanwhile, the desired port‐to‐port isolation is attained by elaborately arranging two resistors between the symmetrical resonators with respect to the central input line. To demonstrate the authors’ design concept, one tri‐band FPD prototype is implemented with good agreement between the simulation results of the electromagnetic simulation software and the measurement results of the vector network analyser. Results show that the new tri‐band FPD exhibits sharp roll‐off with five transmission zeros at passband edges, 17.1 dB harmonic suppression up to 4.6 GHz [2.35f0 (f0 = 1.95 GHz)], and better than 15.7 dB in‐band isolation.

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This letter presents a simple and effective design method for multiband filtering power divider (FPD) in wireless communication systems. By elaborately coupling multiple pairs of stub‐loaded resonators (SLRs) with input/output feedlines, a flexible topology for multiband FPD is built. Not only can each pair of the SLRs generate one passband, but also control the respective center frequency and bandwidth independently. Meanwhile, isolation resistors are arranged between each pair of the SLRs to independently adjust each band isolation, finally achieving nice isolation over a wide frequency band. To validate the design concept, a prototype triple‐band FPD working at 1.30, 1.62, and 2.22 GHz is devised, simulated, and tested. Measurements have good agreement with simulations, indicating that the FPD has the advantages of its independently controllable frequency and bandwidth, high passband selectivity, and good isolation over a broadband frequency band.

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This paper is devoted to a study of the automorphism groups of three series of finite dimensional special odd Hamiltonian superalgebras g over a field of prime characteristic. Our aim is to characterize the connections between the automorphism groups of g and the automorphism groups of the corresponding underlying superalgebras. Precisely speaking, we embed the former into the later. Moreover, we determine the images of the normal series of the automorphism groups and homogeneous automorphism groups of g.

Suppose the ground field is algebraically closed and of characteristic different from 2. In this paper, we described the intrinsic connections among linear super-commuting maps, super-biderivations and centroids for Lie superalgebras satisfying certain assumptions. This is a generalization of the results of Brešar and Zhao on Lie algebras.

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