With the rapid development of mobile communication technology and the explosion of data traffic,high capacity communication with high data transmission rate is urgently needed in densely populated areas.Since multibea...With the rapid development of mobile communication technology and the explosion of data traffic,high capacity communication with high data transmission rate is urgently needed in densely populated areas.Since multibeam antennas are able to increase the communication capacity and support a high data transmission rate,they have attracted a lot of research interest and have been actively investigated for base station applications.In addition,since multi-beam antennas based on Butler matrix(MABBMs)have the advantages of high gain,easy design and low profile,they are suitable for base station applications.The purposes of this paper is to provide an overview of the existing MABBMs.The specifications,principles of operation,design method and implementation of MABBMs are presented.The challenge of MABBMs for 3G/LTE/5G/B5G base station applications is discussed in the end.展开更多
This paper presents the design and implementation of a miniaturized beam steering network that produces broadside beams when it is fed with a compact antenna array.Butler Matrix(BM)was used as the beam steering networ...This paper presents the design and implementation of a miniaturized beam steering network that produces broadside beams when it is fed with a compact antenna array.Butler Matrix(BM)was used as the beam steering network.It was completely built from a miniaturized 3 dB hybrid-couplers in planar microstrip technology.It was configured by feeding the BM with a Planar Inverted-E Antenna(PIEA)array separated at 0.3λas against the 0.5λseparation.This makes the BM produce a major radiation pattern at the broadside.Apart from the miniaturization,no modification was made from the BM side.However,employing effective mutual coupling reduction techniques helped to design the compact PIEA array.The validity of this BM based multibeam PIEA array was demonstrated by comparing the simulation results of the reflection coefficients,transmissions coefficients and the radiation pattern with measurements.The measurement results showed good agreement with simulations.展开更多
With the increasing demand for high speed reliable communications, smart antennas, such as the Butler Matrix array, can be used to develop a system that increases the performance of a wireless system. The Butler matri...With the increasing demand for high speed reliable communications, smart antennas, such as the Butler Matrix array, can be used to develop a system that increases the performance of a wireless system. The Butler matrix is a switched beam array system which can produce orthogonal uniform beams. The main objective is to improve the efficiency of the power in a 90-degree bend. Also, the double-mitered bend is particularly interesting since it provides a substantially lower reflection coefficient and a lower value of S12 at a frequency of 2.4 GHz compared to an unmitered one. Therefore, this paper describes an optimum design using a double-mitered method with a 2 × 2 and a 4 × 4 Butler Matrix array, operating at 2.4 GHz which is used in wireless systems with an FR4 substrate.展开更多
The design and analysis of special type beam former, the Butler matrix, toachieve orthogonal beam-forming networks is presented in this paper. A 4 X 4 microstrip planar arrayantenna is assumed to simulate a 4 X 4 Butl...The design and analysis of special type beam former, the Butler matrix, toachieve orthogonal beam-forming networks is presented in this paper. A 4 X 4 microstrip planar arrayantenna is assumed to simulate a 4 X 4 Butler matrix to demonstrate orthogonal beam forming andbeam steering. The dimensions of rectangular patches in the planar array are chosen according to theDolph-Chebyshev current distribution in order to minimize the side-lobe level ratio for a givenvalue of beamwidth. The simulations are carried out using an antenna design and analysis softwarePCAAD. It is shown that orthogonal beams can be formed to cover about 163° angle with a constantbeam crossover level and high directivity.展开更多
In this paper,a new approach to design terahertz(THz)E-plane crossover coupler is reported.By cascading two symmetrical septum polarizers,a simple structure with wide operating bandwidth and high isolation performance...In this paper,a new approach to design terahertz(THz)E-plane crossover coupler is reported.By cascading two symmetrical septum polarizers,a simple structure with wide operating bandwidth and high isolation performance is achieved.The working principle is explained by operating waveguide modes.To simplify the optimization process,the scattering matrix(S-matrix)of the crossover is calculated.Two prototypes loaded and unloaded electromagnetic band gap(EBG)are fabricated and measured.The electrical contact problem at assembly plane is eliminated by the prototype loaded EBG.A measured bandwidth of 17.3%from 92.5 to 110 GHz for reflection and isolation coefficients<-15 dB and transmission coefficient>-2 dB is achieved.展开更多
文摘With the rapid development of mobile communication technology and the explosion of data traffic,high capacity communication with high data transmission rate is urgently needed in densely populated areas.Since multibeam antennas are able to increase the communication capacity and support a high data transmission rate,they have attracted a lot of research interest and have been actively investigated for base station applications.In addition,since multi-beam antennas based on Butler matrix(MABBMs)have the advantages of high gain,easy design and low profile,they are suitable for base station applications.The purposes of this paper is to provide an overview of the existing MABBMs.The specifications,principles of operation,design method and implementation of MABBMs are presented.The challenge of MABBMs for 3G/LTE/5G/B5G base station applications is discussed in the end.
文摘This paper presents the design and implementation of a miniaturized beam steering network that produces broadside beams when it is fed with a compact antenna array.Butler Matrix(BM)was used as the beam steering network.It was completely built from a miniaturized 3 dB hybrid-couplers in planar microstrip technology.It was configured by feeding the BM with a Planar Inverted-E Antenna(PIEA)array separated at 0.3λas against the 0.5λseparation.This makes the BM produce a major radiation pattern at the broadside.Apart from the miniaturization,no modification was made from the BM side.However,employing effective mutual coupling reduction techniques helped to design the compact PIEA array.The validity of this BM based multibeam PIEA array was demonstrated by comparing the simulation results of the reflection coefficients,transmissions coefficients and the radiation pattern with measurements.The measurement results showed good agreement with simulations.
文摘With the increasing demand for high speed reliable communications, smart antennas, such as the Butler Matrix array, can be used to develop a system that increases the performance of a wireless system. The Butler matrix is a switched beam array system which can produce orthogonal uniform beams. The main objective is to improve the efficiency of the power in a 90-degree bend. Also, the double-mitered bend is particularly interesting since it provides a substantially lower reflection coefficient and a lower value of S12 at a frequency of 2.4 GHz compared to an unmitered one. Therefore, this paper describes an optimum design using a double-mitered method with a 2 × 2 and a 4 × 4 Butler Matrix array, operating at 2.4 GHz which is used in wireless systems with an FR4 substrate.
文摘The design and analysis of special type beam former, the Butler matrix, toachieve orthogonal beam-forming networks is presented in this paper. A 4 X 4 microstrip planar arrayantenna is assumed to simulate a 4 X 4 Butler matrix to demonstrate orthogonal beam forming andbeam steering. The dimensions of rectangular patches in the planar array are chosen according to theDolph-Chebyshev current distribution in order to minimize the side-lobe level ratio for a givenvalue of beamwidth. The simulations are carried out using an antenna design and analysis softwarePCAAD. It is shown that orthogonal beams can be formed to cover about 163° angle with a constantbeam crossover level and high directivity.
基金the National Natural Science Foundation of China under Grant No.61474112 and Grant No.62001039.
文摘In this paper,a new approach to design terahertz(THz)E-plane crossover coupler is reported.By cascading two symmetrical septum polarizers,a simple structure with wide operating bandwidth and high isolation performance is achieved.The working principle is explained by operating waveguide modes.To simplify the optimization process,the scattering matrix(S-matrix)of the crossover is calculated.Two prototypes loaded and unloaded electromagnetic band gap(EBG)are fabricated and measured.The electrical contact problem at assembly plane is eliminated by the prototype loaded EBG.A measured bandwidth of 17.3%from 92.5 to 110 GHz for reflection and isolation coefficients<-15 dB and transmission coefficient>-2 dB is achieved.
