In order to overcome the main drawbacks of coaxial, waveguide, and stripline couplers, the analysis and the design of a compact coaxial-to-microstrip directional coupler convenient for power and antenna control applic...In order to overcome the main drawbacks of coaxial, waveguide, and stripline couplers, the analysis and the design of a compact coaxial-to-microstrip directional coupler convenient for power and antenna control application, are presented using the method of moments (MoM) in two dimensions. This technique is adapted to study the complex configuration of the line’s system, which does not have a simple analytical solution. The modeling of this structure consists in analyzing the primary inductive and capacitive matrices ([L] and [C]). When these matrices are determined, it is possible to calculate the inductive and capacitive coupling coefficients (kL and kC) and estimate the resulting scattering parameters of the coupler using an adapted numerical model. The coupler can be integrated into a printed circuit board (PCB) and operates over 17 to 35 dB coupling coefficients and is always compensated. The compensation is achieved by the proper displacement of a tuning ground plane with respect to the edge of the PCB from 0.1 to 3.3 mm. As an application, we present the design of a compact coupler with 7.5 × 4.8 × 25.8 mm of size and having approximately 20 dB of coupling coefficient at 2 GHz and a minimum directivity of 23.3 dB in the frequency range [0.1 - 4] GHz. In order to check our numerical calculations by the MoM we made simulations in 3D by using CST MICROWAVE STUDIO software for the same geometrical and physical parameters of our designed coupler. The results obtained by the two numerical models (MoM and CST) show a good agreement of the frequency responses of the coaxial-to-microstrip directional coupler. The studied structure represents a great improvement for high power measurement systems, since it has broad-band, good directivity, and can be easily designed and fabricated.展开更多
In this paper, a new idea of reconfigurable 3/6 dB branch line coupler is proposed. The proposed coupler is tuned through a simple open and short circuit at the coupler’s branches’ edges. At the short edges case, a ...In this paper, a new idea of reconfigurable 3/6 dB branch line coupler is proposed. The proposed coupler is tuned through a simple open and short circuit at the coupler’s branches’ edges. At the short edges case, a 3 dB branch line coupler is obtained. In this case, the coupler’s branches are considered as microstrip transmission lines with 0.3 mm slot width which is etched in each coupler’s branch. At the open edges case, the coupler’s branches are considered as asymmetric coupled microstrip lines. In this case, a 6 dB branch line coupler is obtained. Both CST and IE3D simulators are used to optimize the reconfigurable 3/6 dB branch line coupler dimensions. As a prototypes, two BLCs are designed, analyzed and tested at the “on” and “off” states at 2.5 GHz. The measured S-parameters confirm the proposed concept of the reconfigurable 3/6 dB branch line coupler.展开更多
文摘In order to overcome the main drawbacks of coaxial, waveguide, and stripline couplers, the analysis and the design of a compact coaxial-to-microstrip directional coupler convenient for power and antenna control application, are presented using the method of moments (MoM) in two dimensions. This technique is adapted to study the complex configuration of the line’s system, which does not have a simple analytical solution. The modeling of this structure consists in analyzing the primary inductive and capacitive matrices ([L] and [C]). When these matrices are determined, it is possible to calculate the inductive and capacitive coupling coefficients (kL and kC) and estimate the resulting scattering parameters of the coupler using an adapted numerical model. The coupler can be integrated into a printed circuit board (PCB) and operates over 17 to 35 dB coupling coefficients and is always compensated. The compensation is achieved by the proper displacement of a tuning ground plane with respect to the edge of the PCB from 0.1 to 3.3 mm. As an application, we present the design of a compact coupler with 7.5 × 4.8 × 25.8 mm of size and having approximately 20 dB of coupling coefficient at 2 GHz and a minimum directivity of 23.3 dB in the frequency range [0.1 - 4] GHz. In order to check our numerical calculations by the MoM we made simulations in 3D by using CST MICROWAVE STUDIO software for the same geometrical and physical parameters of our designed coupler. The results obtained by the two numerical models (MoM and CST) show a good agreement of the frequency responses of the coaxial-to-microstrip directional coupler. The studied structure represents a great improvement for high power measurement systems, since it has broad-band, good directivity, and can be easily designed and fabricated.
文摘In this paper, a new idea of reconfigurable 3/6 dB branch line coupler is proposed. The proposed coupler is tuned through a simple open and short circuit at the coupler’s branches’ edges. At the short edges case, a 3 dB branch line coupler is obtained. In this case, the coupler’s branches are considered as microstrip transmission lines with 0.3 mm slot width which is etched in each coupler’s branch. At the open edges case, the coupler’s branches are considered as asymmetric coupled microstrip lines. In this case, a 6 dB branch line coupler is obtained. Both CST and IE3D simulators are used to optimize the reconfigurable 3/6 dB branch line coupler dimensions. As a prototypes, two BLCs are designed, analyzed and tested at the “on” and “off” states at 2.5 GHz. The measured S-parameters confirm the proposed concept of the reconfigurable 3/6 dB branch line coupler.
