Application of the N + 2 Transversal Network Method to the Study of a Coupled Resonator Filter

This paper presents a new approach to synthesize admittance function polynomials and coupling matrices for coupled resonator filters. The N + 2 transversal network method is applied to study a coupled resonator filter. This method allowed us to determine the polynomials of the reflection and transmission coefficients. A study is made for a 4 poles filter with 2 transmission zeros between the N + 2 transversal network method and the one found in the literature. A MATLAB code was designed for the numerical simulation of these coefficients for the 6, 8, and 10 pole filter with 4 transmission zeros.

Capacitive Coupled Wide-Notch Stepped Impedance Narrow-Band Bandpass Filter for WiMax Application

The development of wireless communication standards necessitates optimal filter design for the selection of appropriate bands of frequencies.In this work,a compact in size pair of parallel coupled symmetric stepped impedancebased resonator is designed with supporting to the WiMAX communication standards.The coupled resonator is tuned to allow the frequency band between 3.4 GHz and 3.8 GHz,which is centered at 3.6 GHz.A parasitic effect of capacitively coupled feed structure is used for exciting the two symmetrical stepped impedance resonators.The bandwidth and selectivity of the filter are enhanced with the change of characteristic impedances and controlling the coupling gap between resonators.This design offers single narrow sharp passband selectivity as well as multiple stopband harmonic suppression arising as a result of multiple transmission zeros.The designed filter operates with a fractional bandwidth(FBW)of 11.47%.The proposed single narrowband bandpass filter provides better suppression in either side of the tuned frequency(3.6 GHz)without degrading the passband performance.Also,this novel filter offers an insertion loss of about−0.08 dB and a return loss of greater than−30 dB in passband.This approach is useful for eliminating unwanted spurious harmonics responses that enter the desired response.The suggested bandpass filter has been simulated using Advanced Design System(ADS)tool,and the measurement has been made using a network analyzer,and the results are reported.

Single-cavity triangular substrate integrated waveguide bandpass filter with complementary triangular split ring resonator

A novel single-cavity equilateral triangular substrate integrated waveguide(TSIW) bandpass filter(BPF) with a complementary triangular split ring resonator(CTSRR) is designed in this paper. A metallic via-hole is used to split the degenerate modes and adjust the transmission zeros(TZs) properly. Meanwhile, the CTSRR is utilized as a resonator to work together with the degenerate modes of the TSIW cavity. The resonant frequency of the CTSRR can be adjusted by its own size. Meanwhile, a TZ is observed in the lower band due to the CTSRR. Finally, a 16% 3 dB fractional bandwidth(FBW) triple-mode TSIW BPF with three TZs in both lower and upper bands is simulated, fabricated, and measured. There is a good agreement between the simulated and measured ones.

Compact multilayer dual-band bandpass filter design using stepped impedance resonators

Compact dual-band bandpass filter(BPF)for the 5 th generation mobile communication technology(5 G)radio frequency(RF)front-end applications was presented based on multilayer stepped impedance resonators(SIRs).The multilayer dual-band SIR BPF can achieve high selectivity and four transmission zeros(TZs)near the passband edges by the quarter-wavelength tri-section SIRs.The multilayer dual-band SIR BPF is fabricated on a 3-layer FR-4 substrate with a compact dimension of 5.5 mm×5.0 mm×1.2 mm.The measured two passbands of the multilayer dual-band SIR BPF are 3.3 GHz-3.5 GHz and 4.8 GHz-5.0 GHz with insertion loss(IL)less than 2 dB respectively.Both measured and simulated results suggest that it is a possible candidate for the application of 5 G RF front-end at sub-6 GHz frequency band.

A benchmark system to investigate the non-minimum phase behaviour of multi-input multi-output systems

In this paper,the problem of designing a multi-input multi-output(MIMO)systemfor studying the non-minimum phase(NMP)behaviour is considered.For this purpose,a NMP MIMO circuit is proposed and studied under different conditions.The main reason for designing this circuit is the lack of a simple and flexible benchmark for examining different control methods.Due to the simple structure and capability of showing different NMP characteristics,our proposed system is a suitable choice to study the behaviour of these systems.Also,our proposed system can be extended by series and parallel connections to generate more complicated benchmarks.The other advantages of this system are the large number of tunable parameters,adjustable interaction,variable number of poles and zeros,and inexpensive cost.Moreover,this benchmark can be used as a tool for hardware simulation.Finally,an optimal H∞decoupling control is applied to this benchmark to verify its effectiveness.