SPICE simulation of a Combo Wave Generator.How to find sinx given sin2x - Math Notes.SPICE Modeling of tapped air cored inductors.Quick Solutions to Solve SPICE Convergence Issues.Fuse Model For Over-Current Protection Simulation of DC Distribution Systems.Circuit-Breaker Model for Over-Current Protection Simulation of DC Distribution Systems.SPICE modeling of Magnetic Core from Datasheet.SPICE modeling of a JFET from Datasheet.SPICE modeling of a Diode from Datasheet.Single and double-sided board with PCB Designer.Getting Started with OrCAD PCB Designer.
Agilent Technologies, Practical RF Amplifier Design Using the Available Gain Procedure and the Advanced Design System EM/Circuit Co-Simulation Capability, 2009 The American Radio Relay League, The ARRL handbook for RadioĬommunictations, 2013. Operating such equipment and doing this kind of testingĪlso would be important section of final paper. All the necessary equipment, like signal generators, network/spectrum analyzers, noise sources are available at laboratories of VUC and VSRC. Potentiometer R3 is used to precisely trim the bias current.Īfter building this circuit, measurements, like gain-versus-frequency plot, noise figure, third order interception point will be carried out. Upper lead of L1 is AC grounded by C3, so output matching network corresponds to block diagram in figure 6. Also Gmag now exists at 437MHz – amplifier is unconditionally stable.įinal circuit and printed circuit board is shown in figure 9. Gain and noise figure after matching.Īs it can be seen from figure 8, after matching, gain at 437MHz is 20.6dB and noise figure is 1.7dB. Now design can be verified by cascading matching networks, amplifier and stabilization resistor and plotting gain and noise figure versus frequency.įigure 8. Input and output matching L network value determination. 5.6pF and 30nH are selected as standard values.įigure 7. Absolute values are respectively 5.8pF and 28nH.
If stability circle outside smith chart series#
Similarly, normalized values of output matching network are found, which are 1.259 (distance between chart center and cross point in figure 7) for series capacitor and 0.6465 (distance between cross point and the reflection coefficient in figure 7) for shunt inductance.
Input matching is simple – just series capacitor with normalized impedance of 0.088 (conjugate of -0.088 in figure 7) which is 82pF at 437MHz and 50Ω characteristic impedance. Selected matching network topology is high-pass L network or one series capacitor and shunt inductor: To do this, constant impedance and conductance circles, which crosses points of the reflection coefficient to be matched and center of Smith chart. Reflection coefficients are converted to impedances which should be conjugate matched to 50Ω impedance. Optimal input and output reflection coefficients. Using figure above, source reflection coefficientĪre found which gives optimal compromise between gain and noise figure.įigure 5. Constant gain, noise figure and input/output stability circles. Input and output stability circles lays outside of smith chart, which means that amplifier is unconditionally stable or stable with all source and load impedances.įigure 4. Next, after cascading shunt resistor at the output of amplifier, constant gain, noise figure and input/output stability circles are drawn in figure 4.
0 kommentar(er)
