Can I integrate MSL based networks for bandwidth enhancements in LNA designs at GHz frequency range? Any additional parasitics and non-linearity effects will arise
Microstrip lines and other transmission lines are often used at GHz and above because they do not suffer from parasitic effects in the same way or to the same extent that lumped components do at those frequencies. Also because transmission line components become small enough to be practical.
Microstrip circuits do have parasitic effects at open circuits, joins, corners and steps, for instance. These are well known. What must also be taken into account is the almost periodic nature of the impedance of a microstrip line with frequency or length, and also the dispersive nature of microstrip.
I don't think they introduce any non-linear effects, except those due to material properties, which can be largely eliminated by correct choice of materials.
See for instance Article Design of 4-element printed array antenna for ultra-wideband...
I agree with Malcolm White that Microstrip circuits do have parasitic effects on open circuits, etc. You need to investigate all effects via simulation in HFSS or CST.
I also completely agree with Malcoms comment! But, please, take care for higher-order mode excitation in microstrip discontinuities that may have severe influence on fundamental mode propagation as described in my earlier book.
I do not completely agree with Malcolm. It is a serious simplification that may be very dangerous. In reality, any transmission line is a reactance multiplier. It means that it always has a lot of parasitic. In most cases, TL is linear, but the parasitic effect can be huge, especially when the electrical length is close to the one-quarter wavelength multiplier. In this case, reactance (a.k.a. parasitic) changes can be very big because they are determined by the hyperbolic tangent functions, and for close to the one-quarter wavelength multiplier electrical length become asymptotical. In some special cases, TL may be nonlinear. For example, when one of the ends has modulated capacitance (parasitic). Simulation can provide good results but not always. We still have no good theory explaining how the microstrip line works Even today, all designs are based on Dr. Wheeler's empirical equations. The simulation uses Maxwell equations which are a good tool, but you must know exactly all the parasitic involved. And this is almost always not possible, especially when we have discontinuity like bend, connection to via or mechanical connector, etc.
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