The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Direct electromagnetic (EM) optimization for microwave components design is usually a time‐consuming process. To improve the optimization efficiency, this paper proposes a novel parallel EM optimization technique exploiting improved pole‐residue‐based neuro‐transfer function (neuro‐TF) surrogate and isomorphic orthogonal design of experiment (DOE) sampling strategy. We propose a new sampling method...
This paper presents an ultra-wideband variable gain low noise amplifier (UWB-VGLNA). At the input stage, a common-emitter and common-base amplifier with serial-parallel feedback network and active bias network was used to achieve good wideband input impedance matching. At gain-tuning stage, a combinational circuit consisting of active inductor load and Darlington cascode amplifier with gain tuning...
A low power variable gain wideband low noise amplifier (LPVG-LNA) was designed in this paper by using active inductor and multiple current reuse circuit structures. At the input stage of LPVG-LNA, a noise canceling structure and an active inductor were employed to reduce noise figure and to realize input matching and gain tuning respectively. At the middle stage, three common-emitter amplifier was...
A low power dual-band variable gain low noise amplifier (DB-VGLNA) with multiple tunable gain control terminals was designed and implemented. In the proposed DB-VGLNA, a serial-parallel resonant filter network was used to achieve dual-band input impedance matching. In order to enhance gain tunability, three gain-adjustment stages, i.e. cascode amplifier with active inductor as variable load, common-gate...
A novel SiGe HBT low noise amplifier (LNA) was designed by adopting the feedback resistors, which are low cost and implemented easily in VLSI technology. Due to the absence of on-chip spiral inductor, the die area of this novel LNA decreases noticeably. The novel resistive feedback structure of the LNA comprising a shunt feedback loop and a series feedback loop, wherein the shunt feedback loop is...
To adapt to the rapid development of multi-standard mobile communication, a low noise amplifier (LNA) that can operate at two frequencies of 800MHz and 1.8GHz respectively was designed. SiGe HBTs with good noise performance were used in the design. The Cascode circuit topology was adopted to reduce the Miller effect of the transistor. Inductor degeneration in emitter was introduced to decouple the...
On-chip spiral inductors with high quality factors are very important in many RF circuits. In this paper, spiral inductors are analyzed to study the influence of substrate and spiral structure on an inductor's performance in the multi-GHz frequency range. Firstly, the inductors with different substrate conductivity, thickness and permittivity of the dielectric layer are compared, and a general guide...
We report a novel PIN diode SiGe HBT variable gain amplifier (VGA) suited for the standard of WCDMA. The PIN diode which is employed in the feedback loop of the VGA play as a variable resistor to realize the gain control function. By adjusting the bias of the diode, the gain of the VGA can be changed. An inductor is utilized in the feedback loop to reduce the noise figure of the circuit. After matching...
This paper presents a SiGe HBT low noise amplifier (LNA) using resistive feedback scheme for ultra-wideband (UWB) applications. This amplifier is implemented in 0.35 um SiGe process and is unconditionally stable. The simulated results show the LNA has over 21 dB gain with less than 1 dB variation over 3-10 GHz. The matched input and output reflection are all less than -10 dB. The noise figure is 4...
A UWB LNA (low noise amplifier) based on 0.35 ??m SiGe BiCMOS technology is presented in this paper. This LNA adopts a resistance feedback topology to optimize the gain and noise figure. The serial inductance at the base is used to matching input impedance and decreasing group delay variation. The simulation results indicate that the gain of LNA reaches 12.5 dB with the variation of 1.9 dB and the...
A dual wavelength-selectable InGaAsP/InP distributed feedback (DFB) laser with a complex-coupled Bragg grating is presented. An n-doped reverse layer is buried periodically in the index-coupled Bragg grating, which causes a spatial modulation of the carrier concentration in the active region, and so induces the weak gain-coupled to the index-coupled grating. Two wavelengths of 1.51 um and 1.53 um...
Considering the noise correlation term between collector and base current shot noise, there mainly are four noise parameter models of SiGe HBTs, including the unified noise model (UNI), two SPICE noise models (SPN1, SPN2), the thermodynamic noise model (TDN). A comparison of these models was investigated in this work. A SiGe HBT based on BiCMOS process was fabricated and its S-parameters and Minimum...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.