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In this letter, an improved wideband dipole antenna is proposed for BEIDOU/GPS/GLONASS/GALILEO systems. The proposed antenna includes crossed narrow magneto-electric dipoles that are excited by two Γ-shaped strip probes, a 3-dB hybrid coupler, and reflecting plate. The experiment results reveal that the proposed antenna achieves a wide impedance bandwidth of 51.4% (1.1-1.85 GHz) for VSWR

Multi-band navigation receivers have been widely applied in mobile communication systems, and the low noise amplifier (LNA) is an important part of navigation receiver. This paper presents a broadband LNA based on balanced amplifier technique in order to get high gain, low noise figure and smaller size. To improve the LNA's stability, we use microstrip lines to replace traditional small inductors and achieve good results. The simulation and measurement results show that the LNA using balanced amplifier technique is absolutely stable with in the band range of 1.1–1.7 GHz, which can include the band of GPS, GLONASS, Galileo and BeiDou satellite navigation systems. Simulation and experimental results are described detailed.

This letter presents a wideband circularly polarized patch antenna for GPS/GLONASS/BEIDOU/GALILEO systems with reduced multipath effect. The proposed antenna includes four L-probe feeds that are connected the feed network, two circular patches, and a choke ring base. The choke ring base is designed to reduce the multipath effect of the receiver. Experiment results indicate that the bandwidth of the antenna is 50.9% under ${ S}_{11}{ dB from 1.0 to 1.7 GHz, the 3-dB axial-ratio bandwidth is 30.6% from 1.19 to 1.62 GHz, and the measured gains are all above 5 dB in the whole operating band. Moreover, low multipath effect is observed. Both simulated and measured results are presented.

In this paper, a novel Industrial, Scientific, Medical (ISM) band antenna using organic magnetic substrate antenna with frequency selective surface structure is proposed. In order to minimize the antenna's available area, organic magnetic material substrate is used. To increase the available bandwidth and achieve better performance, frequency selective surface structure is adopted. To verify the validity, a 5.56–6.3 GHz wide band patch antenna is fabricated; the simulation results for operating frequency band are shown to have good agreement with measurements.

In this paper, a novel circularly polarized, single-feed microstrip antenna is presented. The operating frequency can be controlled by adjusting the S-slot arm lengths and the feed point. The design has a reduced antenna size compared to the conventional circularly polarized microstrip antenna at a given operating frequency. Further more, the circularly polarized radiation quality is excellent over the entire upper hemisphere. The simulated 10dB return loss bandwidths is about 10% (1500M∼1655M), which covers the global positioning system and Glonass.

Wireless video transmission system obtains the widespread application in the modern society. In this paper, a novel microstrip antenna is introduced for wireless video transmission system. The work includes the design of the unit antenna, the design of the antenna array. Detailed results and conclusion are given in this paper. Simulated results show that the technical specification of the antenna satisfies the wireless video transmission system.

Course design of High-frequency Electronic Circuits is an important practiced process of the course,which has irreplaceable role in the realization of the training target for electronics and communications students. Through the implementation of curriculum design, students can understand the basic theoretical knowledge better; master the key technology and improve the ability of training, design thinking and innovation. Small low-cost production is the title among the courses, from which, we can arouse the practical ability of students, let students finish the processes of schematic design, component selection, circuit debugging. Students can combine theory and practical knowledge to enhance their ability and the role course design of High-frequency Electronic Circuits can be achieved really.

This paper describes a novel dual-band patch antenna on organic magnetic substrate for wireless local area networks (WLAN) wireless communication (at 2.4 and 5 GHz). The dual-band operation is obtained by embedding a pair of L-shaped slots. The magnetic material is adopted because the substrate can reduce the size of antenna 40%, comparing with rectangular microstrip antennas on normal dielectric substrate, and have wider bandwidths for both bands. Details of the proposed antenna design are presented and discussed, which can be a candidate for the requirement of WLAN, operating in 2.4 and 5GHz.

A novel ultra-wideband (UWB) coplanar patch antenna (CPA)with L-CPW fed is proposed with a wider impedance bandwidth than that of the conventional CPW fed patch antenna. A L-CPW was used to widen the bandwidth of the coplanar patch antenna. The antenna, operating at 7.7GHz was designed and fabricated. The results of return loss, radiation pattern and gain, both simulated and measured, were presented. A Good agreement between the simulation and measurement has been observed. The antenna has an impedance bandwidth at 10dB return loss about 17% and stable radiation patterns, which is suitable for the application of UWB.

A novel three dimension coplanar waveguide (CPW) fed bow-tie antenna for 1.67 GHz and 2.4 GHz is designed in this letter. The antenna consists of a slotted bow-tie antenna and an independent feed network. Part of CPW fed network is located in a separate microwave substrate. Two microwave substrates are connected and combined with an arbitrary angle of view in three-dimensional-space. By adjusting the bow-tie slot in the ground plane and U-slot on the top of the patch, good radiation characteristics and reasonable gain values can achieved with return loss below -lOdB. Detailed simulated results are presented.

The characteristic impedance of asymmetrical coplanar waveguide (ACPW) was calculated using multi-resolution time domain (MRTD) method which based on Daubechies compactly supported scaling functions. The good agreement between this paper and the conventional FDTD method was obtained. Efficiency of MRTD method was compared with FDTD method. Time and frequency domain results have been presented and explained. The curves of characteristic impedance varying with frequency were drawn from 1GHz to 60GHz. The effect of side strip width on characteristic impedance was analyzed.

This paper describes a novel microstrip antenna on organic magnetic substrate for WLAN systems. The dual-band operation is obtainer by embedding a pair of L-shaped slots. The organic magnetic material is adopted because the substrate can reduce size of the antenna 4000, comparing with a rectangular microstrip antenna on normal dielectric substrate, and have wider bandwidths for both bands. Details of the proposed antenna design are presented and discussed, which can be candidate for the requirement of WLAN, operating in 2.45, 4.9 and 5.25GHz.

The paper presents a detailed analysis of characteristic impedance of asymmetric coplanar waveguide (ACPW) using the finite-difference time-domain (FDTD) method, and the results agree well with available theoretical and experimental data over a wide frequency range. The transient propagating waveforms along the ACPW, which are excited by retarded Gaussian pulse, are found in the time domain. After the time-domain field distributions are obtained, frequency-domain parameters such as the characteristic impedance are calculated using Fourier transformations. Index Terms-Asymmetric coplanar waveguide (ACPW),Finite-difference time-domain (FDTD) method,Absorb boundary condition,Characteristic impedance