Simulation of microwave optical links and proof of noise figure lower than electrical losses

2010 ◽  
Vol 2 (6) ◽  
pp. 497-503 ◽  
Author(s):  
Anne-Laure Billabert ◽  
Mourad Chtioui ◽  
Christian Rumelhard ◽  
Catherine Algani ◽  
Mehdi Alouini ◽  
...  
Keyword(s):  
Noise Figure ◽  
Direct Detection ◽  
Impedance Matching ◽  
Electrical Network ◽  
Simulation Tool ◽  
Unusual Behavior ◽  
Optical Links ◽  
Operation Conditions ◽  
Laser Dynamics ◽  
Theoretical Predictions

The operation of a microwave photonic link is thoroughly investigated both theoretically and experimentally. To this aim, we have developed a simulation tool based on an accurate physical model embedded in a radio frequency (RF) chain simulator. The theoretical predictions are tested on an intensity modulation-direct detection (IMDD) link we have specifically developed to this purpose. Our simulation tool takes into account both optical and electrical characteristics of the link components including the laser dynamics and impedance matching networks. It thus enables an accurate understanding of the different physical and electrical phenomena governing the link's performances even under unusual operation conditions. Specifically, we were able to isolate an unusual behavior and to confirm it experimentally. It is thereby clear that the noise figure of a microwave optical link can be lower than the electrical losses, such as a mismatched output passive electrical network. This state is reached when the optical losses are high enough and when the link's output impedance is mismatched, too.

ON-CHIP INDUCTORS OPTIMIZATION FOR ULTRA WIDE BAND LOW NOISE AMPLIFIERS

2011 ◽  
Vol 20 (07) ◽  
pp. 1231-1242 ◽  
Author(s):  
J. DEL PINO ◽  
SUNIL L. KHEMCHANDANI ◽  
ROBERTO DÍAZ-ORTEGA ◽  
R. PULIDO ◽  
H. GARCÍA-VÁZQUEZ
Keyword(s):  
Quality Factor ◽  
Noise Figure ◽  
Impedance Matching ◽  
Broad Band ◽  
Wide Band ◽  
Design Guidelines ◽  
Low Noise ◽  
Low Noise Amplifiers ◽  
Integrated Inductor ◽  
On Chip

In this work, the influence of the inductor quality factor in wide band low noise amplifiers has been studied. Electromagnetic simulations have been used to model the integrated inductor broad band response. The influence of the quality factor on LNA performance of the inductors that compound the impedance matching networks, inductive degeneration and broadband load has been studied, obtaining design guidelines for optimizing the amplifier gain flatness. Using this guidelines, an LNA with wideband input matching, shunt-peaking load, and an output buffer was designed. Using Austria Mikro Systems BiCMOS 0.35 m process, a prototype has been fabricated achieving the following measured specifications: maximum gain of 12.5 dB at 3.4 GHz with a -3 dB bandwidth of 1.7–5.3 GHz, noise figure from 4.3 to 5.2 dB, and unity gain at 9.4 GHz.

Research and Analysis of Tunable Differential N-Path Band-Pass Filter

2020 ◽  
pp. 2150055
Author(s):  
Shuxiang Song ◽  
Guolun Liu ◽  
Mingcan Cen ◽  
Chaobo Cai
Keyword(s):  
Bandpass Filter ◽  
Noise Figure ◽  
Supply Voltage ◽  
Impedance Matching ◽  
Transmission Function ◽  
Center Frequency ◽  
Cmos Process ◽  
Band Pass Filter ◽  
Pass Filter ◽  
Circuit Structure

Traditional filters usually have low Q and gain values and it is difficult to adjust their center frequencies. Moreover, it is very complicated to analyze their transmission charateristics through conventional methods. Therefore, in this paper, a tunable differential N-path bandpass filter that uses a new adjoint network method to analyze the transmission characteristics of the differential N-path structure is proposed. The filter circuit adopts a novel circuit structure consisting of two differential N-path structures, two transconductance amplifiers and an off-chip transformer. The differential structure eliminates even harmonics, the transconductance amplifier increases the circuit gain and the off-chip transformer acts as a balun, improving the filter’s Q value and achieving impedance matching. Unlike the traditional switching capacitance method used for analyzing the differential circuit structure, the method proposed in this paper does not involve complicated calculus operations. In fact, the method greatly simplifies these complex operations, and the transmission function of the circuit can be obtained through simple algebraic operations. The proposed filter was designed using TSMC 180[Formula: see text]nm CMOS process. Simulation results for a differential four-path bandpass filter formed under 1.2[Formula: see text]V supply voltage show that the gain of the filter is greater than 8.5 dB, the center frequency can be adjusted from 0.1[Formula: see text]GHz to 1[Formula: see text]GHz, the in-band insertion loss S11 is greater than 10 dB, the out-of-band IIP3 is greater than 10 dBm, the out-of-band rejection is 28 dB and the noise figure is less than 2.2 dB at [Formula: see text][Formula: see text]MHz.

Design of Low-Noise Two-Path Amplifier for 6–16 GHz Applications

2020 ◽  
pp. 2150136
Author(s):  
Asieh Parhizkar Tarighat ◽  
Mostafa Yargholi
Keyword(s):  
Noise Figure ◽  
Impedance Matching ◽  
High Gain ◽  
Low Noise ◽  
Cmos Process ◽  
Input Matching ◽  
Inductive Peaking ◽  
Linearity Improvement ◽  
Noise Amplifier ◽  
Path Structure

A two-path low-noise amplifier (LNA) is designed with TSMC 0.18[Formula: see text][Formula: see text]m standard RF CMOS process for 6–16[Formula: see text]GHz frequency band applications. The principle of a conventional resistive shunt feedback LNA is analyzed to demonstrate the trade-off between the noise figure (NF) and the input matching. To alleviate the mentioned issue for wideband application, this structure with noise canceling technique and linearity improvement are applied to a two-path structure. Flat and high gain is supplied by the primary path; while the input and output impedance matching are provided by the secondary path. The [Formula: see text][Formula: see text]dB bandwidth can be increased to a higher frequency by inductive peaking, which is used at the first stage of the two paths. Besides, by biasing the transistors at the threshold voltage, low power dissipation is achieved. The [Formula: see text][Formula: see text]dB gain bandwidth of the proposed LNA is 10[Formula: see text]GHz, while the maximum power gain of 13.1[Formula: see text]dB is attained. With this structure, minimum NF of 4.6[Formula: see text]dB and noise flatness of 1[Formula: see text]dB in the whole bandwidth can be achieved. The input impedance is matched, and S[Formula: see text] is lower than [Formula: see text]10 dB. With the proposed linearized LNA, the average IIP[Formula: see text][Formula: see text]dBm is gained, while it occupies 1051.7[Formula: see text][Formula: see text]m die area.

Design and modeling of an ultra-wideband low-noise distributed amplifier in InP DHBT technology

2019 ◽  
Vol 11 (7) ◽  
pp. 635-644 ◽  
Author(s):  
T. Shivan ◽  
E. Kaule ◽  
M. Hossain ◽  
R. Doerner ◽  
T. Johansen ◽  
...  
Keyword(s):  
Noise Figure ◽  
Impedance Matching ◽  
Low Noise ◽  
Ultra Wideband ◽  
Frequency Range ◽  
Collector Current ◽  
Noise Sources ◽  
Distributed Amplifier ◽  
Double Heterojunction ◽  
High Bandwidth

AbstractThis paper reports on an ultra-wideband low-noise distributed amplifier (LNDA) in a transferred-substrate InP double heterojunction bipolar transistor (DHBT) technology which exhibits a uniform low-noise characteristic over a large frequency range. To obtain very high bandwidth, a distributed architecture has been chosen with cascode unit gain cells. Each unit cell consists of two cascode-connected transistors with 500 nm emitter length and ft/fmax of ~360/492 GHz, respectively. Due to optimum line-impedance matching, low common-base transistor capacitance, and low collector-current operation, the circuit exhibits a low-noise figure (NF) over a broad frequency range. A 3-dB bandwidth from 40 to 185 GHz is measured, with an NF of 8 dB within the frequency range between 75 and 105 GHz. Moreover, this circuit demonstrates the widest 3-dB bandwidth operation among all reported single-stage amplifiers with a cascode configuration. Additionally, this work has proposed that the noise sources of the InP DHBTs are largely uncorrelated. As a result, a reliable prediction can be done for the NF of ultra-wideband circuits beyond the frequency range of the measurement equipment.

scholarly journals Evaluation of the Influence of Non-sinusoidal Conditions on Power Transformers

2018 ◽  
Vol 58 ◽  
pp. 03012
Author(s):  
Lidiia Kovernikova ◽  
Ngo Van Cuong
Keyword(s):  
Cost Effective ◽  
Electrical Equipment ◽  
Power Transformers ◽  
Electrical Network ◽  
Operating Parameters ◽  
Electrical Networks ◽  
Equipment Operation ◽  
Traction Substation ◽  
Operation Conditions ◽  
Railway Traction

The electrical equipment operation is cost-effective and reliable when operating parameters of the electrical network correspond to the rated data of the equipment. The real operation conditions, however, differ from those required for electrical equipment, which negatively affects its efficiency. The non-sinusoidal conditions in electrical networks are currently very common. The paper provides an overview of the characteristics obtained from an analysis of publications, which are used to evaluate the effect of the non-sinusoidal conditions on power transformers. The results of the calculation of these characteristics for a transformer installed at a railway traction substation are presented. Parameters of the non-sinusoidal conditions are obtained as a result of measurements.

A Full Integrated LNA in 0.18μm SiGe BiCMOS Technology

2013 ◽  
Vol 380-384 ◽  
pp. 3287-3291
Author(s):  
Bing Liang Yu ◽  
Xiao Ning Xie ◽  
Wen Yuan Li
Keyword(s):  
Wireless Local Area Network ◽  
Local Area Network ◽  
Noise Figure ◽  
Impedance Matching ◽  
Local Area ◽  
Low Noise ◽  
Area Network ◽  
Bicmos Technology ◽  
Sige Bicmos ◽  
Noise Amplifier

A fully integrated low noise amplifier (LNA) for wireless local area network (WLAN) application is presents. The circuit is fabricated in 0.18μm SiGe BiCMOS technology. For the low noise figure, a feedback path is introduced into the traditional inductively degenerated common emitter cascade LNA, which decreases the inductance for input impedance matching, therefore reduces the thermal noise caused by loss resistor. Impedance matching and noise matching are achieved at the same time. Measured results show that the resonance point of the output resonance network shifts from 2.4GHz to 2.8GHz, due to the parasitic effects at the output. At the frequency of 2.8GHz, the LNA achieves 2.2dB noise figure, 19.4dB power gain. The core circuit consumes only 13mW from a 1.8V supply and occupies less than 0.5mm2.

Surge Cycle of Turbochargers: Simulation and Comparison to Experiments

2004 ◽  
Author(s):  
M. B. Schmitz ◽  
G. Fitzky
Keyword(s):  
Static Pressure ◽  
Test Facility ◽  
Test Rig ◽  
Time Resolved ◽  
Operation Conditions ◽  
Operation Modes ◽  
Second Mode ◽  
Theoretical Predictions ◽  
Compressor Map ◽  
Work Done

The turbocharger test facility can be operated in two different modes. In the first mode, the turbocharger turbine is driven by an external blower and a combustor. The compressor blows off through the chimney. In the second mode the turbocharger is operated similar to a gas turbine: the turbine drives the turbocharger compressor which pressurizes the combustion chamber. This study is focused on the surge cycle of the turbocharger for both operation modes of the test facility. The turbocharger has to withstand surge for all pressure ratios it is designed for without damaging the test rig. Especially for small compressors large plenum volumes can cause such damages. The dynamical model of the system is developed based on the work done by Greitzer [5], [6] and has been extended to the special requirements of the turbocharger test rig. For the components of the turbocharger a quasi-steady behavior with respect to the time scales of the surge cycle is assumed. Consequently, the experimentally obtained steady state characteristics for both compressor and turbine are applied to the model. In order to describe the compressor behavior for backflow conditions, the compressor map is extended for negative mass flow. The theoretical model is calibrated on experimental data. Thereafter the model is used to predict the surge cycle for different operation conditions. For the two operation modes, the blow-off and the recirculation operation, the time resolved values of static pressure and speed oscillation were recorded and compared to the theoretical predictions.

scholarly journals Wideband ring mixer for band #1 of MB-OFDM systems in 180 nm CMOS technology

2021 ◽  
Vol 72 (5) ◽  
pp. 323-329
Author(s):  
Abhay Chaturvedi ◽  
Mithilesh Kumar ◽  
Ram Swaroop Meena ◽  
Gaurav Kumar Sharma
Keyword(s):  
Integrated Circuit ◽  
Orthogonal Frequency Division Multiplexing ◽  
Noise Figure ◽  
Impedance Matching ◽  
Cmos Technology ◽  
Ofdm Systems ◽  
Ofdm System ◽  
Integrated Circuit Design ◽  
Wireless Receiver ◽  
Down Conversion

Abstract A wideband down conversion ring mixer is proposed for multi band orthogonal frequency division multiplexing (MB-OFDM) system in 180 nm CMOS technology. The mixer is essentially used in a heterodyne wireless receiver to enhance the selectivity of the system. Being a nonlinear system, the mixer dominates the overall performance of the system. The design of down conversion mixer is the most challenging part of a receive chain. Wideband impedance matching always remains a challenge in any radio frequency integrated circuit design. This paper presents the design of a ring mixer with high linearity, wideband impedance matching using differential resistive impedance matching and without using any DC bias. The proposed mixer is tuned for a frequency of 3.432 GHz of band 1 of the MB-OFDM system. Mixer core is based on the FET ring mixer topology. The mixer is implemented in 180 nm CMOS technology. The mixer achieves the minimum conversion loss of 10.49 dB, 1 dB compression point (P1) of 12.40 dBm, third order input intercept point (IIP3) of 12.01 dBm, a minimum SSB noise figure of 8.99 dB, and S 11 of less than -10 dB over the frequency range of 0 to 13.61 GHz . The layout of the mixer records an active area of 183.75 μm 2 .

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