Design Of A Miniaturized Three-way Power Divider For Harmonic Suppressio

The power divider is a device that divides a single input microwave signal into multiple outputs,and is widely used in the phased array radar’s multi-channel analog beamforming and the phased array antenna feed network.The appearance of the three-way power divider provides a new idea for the design of phased array radars with non-2~N signal channels,and the power divider that integrates harmonic suppression and filtering functions makes the local oscillator power divider network of the mixer front end no need to cascade additional filter circuits,which is conducive to the simplification of the number of channels and the miniaturization of the array frequency conversion system.In addition,the triangular grid antenna array with compact array element arrangement also puts forward an urgent demand for the three-way feed network.Based on the above application background,this paper starts with three different power division structures,designs and measures a number of miniaturized three-channel planar power dividers with harmonic suppression and filtering functions.The main work and innovations of the paper are as follows:Firstly,the theoretical analysis and simulation of the cascaded three-way power divider based on power recombination are carried out,and the influence of the inter-stage connection lines of different electrical lengths on the transmission performance of the power divider is analyzed,and the harmonic suppression function is designed based on this structure.The three-way power divider.The transition structure between cascaded devices is selected as the adjustment variable for impedance matching and circuit layout,and the principle of harmonic suppression of branch line resonators is used to achieve second and third harmonic suppression on a planar circuit.Secondly,in order to make up for the shortcomings of the inconsistency between the insertion loss and the output end of the cascaded three-way power divider,a parity-like analysis method suitable for the three-way symmetric Wilkinson power divider is proposed and designed accordingly.A three-way power divider with a ring-shaped symmetrical structure.The designed power divider achieves the suppression of the second and third harmonics while completing the miniaturized layout.The loop circuit area is onlyπ(λ_g/8)~2.The test results show that the device has good in-band transmission performance and the output amplitude and phase consistency is enough.Furthermore,with the Luzzatto power divider as the basic structure,a miniaturized three-way Luzzatto filter power divider is designed.By discussing the feasible form of the isolation network between adjacent output ports and its filtering response,it is proposed to use 6 half-wavelength lines in the isolation network to achieve the bandpass filtering performance of the power splitter,reaching a relative bandwidth of 49.5%,and the folded microstrip lines reduce the radius of the loop circuit toλ_g/8.Finally,in order to improve the out-of-band harmonic suppression of the above-mentioned Luzzatto filtering power divider,an improved double-harmonic suppression miniaturized T-shaped structure was proposed to replace the quarter-wavelength line of the Luzzatto power divider,and two designs were designed.Three-way miniaturized filter power divider with harmonic suppression function.The dimensions of the two plane circuits are bothπ(λ_g/8)~2.The first one achieves 35.1d B suppression at the second harmonic frequency,and the second one achieves 32.8d B and 39.2d B suppression at the second and third harmonics,respectively.The actual processing measurement results are consistent with the simulation data.In summary,this article takes the three-way power divider as the research object,and gradually proposes three power divider designs that meet the planar layout,and explores the design ideas of multi-functional integration from different ways.The functional miniaturized filter power divider provides several design solutions to miniaturized three-way dividers for filtering and harmonic-suppression responses.