Low Electromagnetic Coupling Achievement of a Quad-Element UWB MIMO Antenna Using Miniaturization Technique
Aicha Mchbal,
Naima Amar Touhami,
Abdelhafid Marroun
Issue:
Volume 11, Issue 3, June 2023
Pages:
67-76
Received:
5 May 2023
Accepted:
31 May 2023
Published:
20 June 2023
Abstract: This research presents a study of a four-element MIMO antenna, whose objective is to design a miniaturized or a reduced inter-elements spacing of a quad–element MIMO antenna that operates in UWB spectrum ranging between 3.1-10.6 GHz, and that characterizes by a reduced inter-element electromagnetic coupling which is due to nearfield coupling and surface current propagation between ports. The proposed MIMO antenna radiating elements are developed from a simple rectangular patch antenna. With the aim to reduce the electromagnetic coupling between radiators and cover the whole UWB bandwidth, diverse techniques are employed, including the employment of the polarization diversity technique, whereas the use of decoupling structures is prevented so as to avoid a bulky antenna assembly. Measurements show that the studied UWB MIMO antenna is characterized by a good compactness whose dimension is about 31×31×0.8 mm3, and it offers a -10 dB impedance bandwidth of 3-12.8 GHz, a mutual coupling <-15 dB, correlation coefficients<0.3, a diversity gain of about 8.75 and a total active reflection coefficient less than -12 dB. Results prove that despite of the miniaturized size of the studied antenna assembly and the disuse of decoupling mechanisms, the presented antenna provides potential diversity performances for use in UWB applications.
Abstract: This research presents a study of a four-element MIMO antenna, whose objective is to design a miniaturized or a reduced inter-elements spacing of a quad–element MIMO antenna that operates in UWB spectrum ranging between 3.1-10.6 GHz, and that characterizes by a reduced inter-element electromagnetic coupling which is due to nearfield coupling and su...
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Research on Optimization of CNC Milling Process Parameters Based on Carbon Emission
Juan Wei,
Yaxin Wei,
Mengdi Wei,
Simin Ren
Issue:
Volume 11, Issue 3, June 2023
Pages:
77-81
Received:
10 April 2023
Accepted:
17 June 2023
Published:
27 June 2023
Abstract: In order to achieve the low carbon and efficient working effect of CNC machine tools, this paper takes the 2243 VMC machining centre as the research object to study the problem between carbon emission and time, cost and process parameters in the machining process of machining centre machine tools, and establish the optimization model of CNC milling process parameters based on carbon emission. Carbon emissions, machining cost and machining time are taken as the optimisation objectives, tool life, roughness and machine power are taken as constraints, and spindle speed, feed per tooth, cutting width and depth of cut are taken as optimisation variables. The model is solved using a particle swarm algorithm (PSO) to produce a Pareto solution set for multi-objective optimisation. Finally, the optimisation results were compared with the calculated results for the empirical parameters to verify the feasibility of the model. The results show that the calculated results for the optimised parameters provide a 19.53% reduction in carbon emissions, a 12.96% reduction in processing costs and a 13.72% reduction in processing time after optimisation by the algorithm compared to the calculated results for the empirical parameters, indicating that the algorithm provides a better optimisation than the empirical parameters.
Abstract: In order to achieve the low carbon and efficient working effect of CNC machine tools, this paper takes the 2243 VMC machining centre as the research object to study the problem between carbon emission and time, cost and process parameters in the machining process of machining centre machine tools, and establish the optimization model of CNC milling...
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