The Experts below are selected from a list of 4560 Experts worldwide ranked by ideXlab platform
Mohsen Hayati - One of the best experts on this subject based on the ideXlab platform.
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compact microstrip Lowpass Filter using meandered unequal t shaped resonator with ultra wide rejection band
Aeu-international Journal of Electronics and Communications, 2018Co-Authors: Farzin Shama, Mohsen Hayati, Milad EkhteraeiAbstract:Abstract In this paper, a compact Lowpass Filter (LPF) with ultra-wide rejection band has been presented. In fact, a novel meandered semi-hairpin resonator has been used and the stopband characteristics have been improved by using a combinatorial suppressing unit. The suppressing unit contains a combination between T-shaped and semi-circular patches, which are loaded symmetrically to the designed resonator. For the proposed LPF, the-3 dB cut-off frequency has been adjusted to 2.2 GHz. After simulations, the proposed LPF has been fabricated and tested. The experimental results validated that the rejection bandwidth is expanded from 2.471 GHz to 28.62 GHz with corresponding attenuation level of −20 dB. The transition band is only 0.271 GHz from 2.2 GHz to 2.471 GHz with corresponding attenuation levels of −3 dB to −20 dB, respectively. In addition, the measured maximum insertion loss and return loss in the passband, from DC to 2.04 GHz (93% of the passband region) are 0.2 dB and 17 dB, respectively.
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compact Lowpass Filter with flat group delay using lattice shaped resonator
Electronics Letters, 2017Co-Authors: Mohsen Hayati, Milad Ekhteraei, Farzin ShamaAbstract:A compact Lowpass Filter (LPF) using a lattice-shaped resonator is presented with a wide rejection band and sharp roll-off. The designed LPF has −3 dB cut-off frequency at 4.34 GHz. The fabricated LPF is simulated and tested; there is a good agreement between the simulation and experimental results. Experimental results show that the maximum variation of flat group delay is only 0.3 ns in the passband. Also, the measured return-loss and insertion loss are more than 19 dB and <0.1 dB in 88% of the passband region, respectively. The size of the designed Filter is only 22.5 × 8.65 mm2.
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design of a compact microstrip Lowpass Filter with sharp roll off using combined t shaped and l shaped resonators
Electronics Letters, 2016Co-Authors: M Jahanbakhshi, Mohsen HayatiAbstract:A novel compact microstrip Lowpass Filter with high performance is designed and analysed based on transfer function. The main resonator consists of L-shaped and T-shaped patches. The L-shaped resonator is used to increase the width of the stopband. The presented Filter has -3 dB cut-off frequency at 2 GHz. It also has a wide stopband about 17.82 GHz with the suppression level of -21 dB. The transition band is ~168 MHz from -3 to -40 dB. The locations of transmission zeros are calculated by transfer function. The presented Lowpass Filter has other advantages, such as high return loss more than 20 dB and low insertion loss <;0.15 dB in the passband. The size of the Filter is only 0.087 × 0.170 λ g 2 , where λ g is the guided wavelength at the cut-off frequency. The proposed Lowpass Filter has the figure of merit of 50,285, which shows its strong efficiency. The Lowpass Filter is simulated and fabricated and there is a good agreement between the simulation and measurement results.
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A miniaturized harmonic suppressed power amplifier integrated with Lowpass Filter for long term evolution application
Analog Integrated Circuits and Signal Processing, 2016Co-Authors: Saeed Roshani, Mohsen Hayati, Saeed Setayeshi, Golshan MohamadpourAbstract:A compact power amplifier matched by a proposed Lowpass Filter (LPF) with nth harmonics suppression is presented in this paper. In the proposed PA, the LPF is applied as an output transformer network, which transforms 50 Ω to the desired impedance to have maximum power. In this method the conventional output matching network is eliminated, which results in the 26 % size reduction of the proposed PA as compared with the conventional one. Moreover, using the LPF at the output impressively suppresses the harmonics (2nd–5th) with high levels of attenuation. The proposed PA is designed at the 2.6 GHz, which is suitable for LTE applications. The simulated and measured results are in the good agreement, which confirm the validity of the proposed design.
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compact microstrip Lowpass Filter with wide stopband and very sharp roll off
Electronics Letters, 2016Co-Authors: Mohsen Hayati, Meysam Akbari, R SalahiAbstract:A novel microstrip Lowpass Filter (LPF) with good specifications such as wide stopband and sharp roll-off is reported. The Filter structure consists of split ring resonator loaded by folded polygene patches. The proposed Filter with −3 dB cut-off frequency at 1.57 GHz has been designed, fabricated and measured. The LPF has a wide stopband from 1.67 to 14 GHz with a rejection level greater than −20 dB, sharp roll-off rate equal to 170 dB/GHz and low insertion loss lower than 0.13 dB in 94% of the passband. Finally, a high figure of merit of 51,178 is obtained.
Qiuting Huang - One of the best experts on this subject based on the ideXlab platform.
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mixed analog digital fir iir realization of a linear phase Lowpass Filter
IEEE Journal of Solid-state Circuits, 1996Co-Authors: Qiuting HuangAbstract:A 5 kHz linear-phase Lowpass Filter is implemented in a 2-/spl mu/m BiCMOS technology as a combination of sigma-delta front-end, a digital shift register, a switched capacitor (SC) summer circuit with 50 input capacitors, and an SC biquad running at a 1 MHz clock. The measured group delay variation in the passband is less than 1 /spl mu/s and the measured total harmonic distortion (THD) is -80 dB for an input sine wave amplitude of 0.7 V at 1 kHz. The circuit consumes 80 mW from /spl plusmn/5 V supply and measures 8.12 mm/sup 2/ without pads.
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a 100 tap fir iir analog linear phase Lowpass Filter
Symposium on VLSI Circuits, 1995Co-Authors: Qiuting Huang, P T Maguire, Thomas BurgerAbstract:A 5 kHz linear-phase Lowpass Filter is implemented in a 2-/spl mu/m BiCMOS technology as a combination of a sigma-delta front-end, a digital shift register, an SC summer circuit of 50 input capacitors and an SC biquad running at a 1 MHz clock. The measured group delay variation in the passband is less than 1 /spl mu/s and the measured THD is -80 dB for an input sine wave amplitude of 0.7 V at 1 kHz.
Dharmendra K. Upadhyay - One of the best experts on this subject based on the ideXlab platform.
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Active realization of fractional order Butterworth Lowpass Filter using DVCC
Journal of King Saud University - Engineering Sciences, 2020Co-Authors: Shalabh Kumar Mishra, Maneesha Gupta, Dharmendra K. UpadhyayAbstract:Abstract This paper presents an active realization of fraction order Butterworth Lowpass Filter using a differential voltage current conveyor (DVCC) and two fractance devices (FDs). Initially, the DVCC based fractional order system transfer function is developed. Then, the transfer function of the developed system is equated with the standard fractional order Butterworth equation. By equating this, the generalized condition is obtained for which the developed system behaves like a fractional order Butterworth Filter. Further, the effect of current and voltage tracking errors of DVCC, on the system response is investigated using Monte Carlo analysis. Stability of the proposed fractional order Butterworth Filter is investigated by pole-zero analysis in complex W-plane. Moreover, the dependency of Filter cutoff frequency, on various circuit parameters are investigated using 3D plots. Finally to validate the theoretical results, proposed fractional order Butterworth Filter is simulated using R-C ladder network based fractional order capacitor, in PSpice environment using 0.5 μm MIETEC CMOS technology.
A Buchwald - One of the best experts on this subject based on the ideXlab platform.
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10 mhz 60 db dynamic range 4th order butterworth Lowpass Filter
European Solid-State Circuits Conference, 1997Co-Authors: D Cheung, K Bult, A BuchwaldAbstract:A 4th-order Butterworth Lowpass continuous-time Filter, based on transconductance-C integrators, for applications in the videofrequency range is presented. Fabricated in a standard 0.8µm CMOS technology (MOSIS HPCMOS26G), the circuit occupies an area of 0.59mm2, including the automatic tuning circuitry, and dissipates 40- mW from a single 5V supply. A simple transconductor is utilized, which provides good linearity and high-speed properties. Experimental results of a 10-MHz, 60-dB dynamic-range, Lowpass Filter are given.
Cheung Darwin - One of the best experts on this subject based on the ideXlab platform.
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10-MHz 60-dB dynamic-range 4th-Order Butterworth Lowpass Filter
1996Co-Authors: Cheung DarwinAbstract:CMOS circuits for integrated continuous-time analog Filters, applicable to lo-bit resolution video-rate signal processing systems, are presented. The Filters utilize transconductance-C integrators as fundamental building blocks. A differential transconductance element comprising a source-coupled pair with a poly-silicon degeneration resistor and a cross-coupled high-impedance load is described. With this transconductor, tunable integrators for very-high-frequency in-tegrated Filters can be realized. Good high-speed properties stem from the absence of internal nodes, which pushes non-dominant poles to the gigahertz range. These integrators are optimized for the maximum dynamic-range of greater than 64-dB, which occurs for input signal levels of 200-mV. Dual feedback loops stabilize circuit performance against temperature- and process-variations. The resonant frequency of a master VCO, comprising back-to-back integrators, tracks the frequency of a stable reference clock by virtue of an on-chip PLL. The VCO control voltage is broadcast to all matched transconductors, thus accurately controlling the natural frequencies of the Filter. A separate Q-tuning loop controls the dissipation of the integrator, thus insuring a. 90-degree phase shift at the resonant frequency. Experimental results of a l0-MHz, 60-dB dynamic-range, 4th-Order Butterworth Lowpass Filter, realized in a O.8μm CMOS process, are given. The Filter consists of a cascade of two biquadratic sections. Results show total harmonic disortion of less than -60-dB for a 130-mV input signal at 2-MHz. Third-order inter modulation distortion is below -56-dB for inputs of 8-MHz and 9-MHz. The measured Filter responses agree with simulation results for the passive prototype Filter to within 10%. The circuit occupies an area of 0.91mm x 0.65mm = 0.59mm2, and dissipates 40-mW from a single 5V supply
