microstrip t line coaxial -antenna
I need information regarding the connection of coaxial cable (SMA edge mount) to microstrip line on a PCB.
I saw that there is a tapering technique to maintain constant impedance from the SMA connector to the microstrip but I didnt see literature about it.
Can you please help me?
Regards,
The basic idea is to bring a 50 Ohm ms line to the coax and solder together. The devil is in the details. One has to pay close attention to the dimensions of both the PCB and particular connector in play. Below 2 GHz you can hardly go wrong but higher in frequency it gets to be amusing.
I am not sure that the technical literature is the place to look for specific guidance. Try the manufacturer of your selected connector. That should be fun too as they often cheerfully guarantee their stuff to the interface and then disavow any knowledge of what to do next. The usual line is "there are just too many possibilities to make a recommendation".
Model your particular junction and see if the simulator suggests that you have a problem.
I would also consider the mechanical strength of the assembly to see if the connection is sufficiently strong for your application.
You can handle the edge mount SMA like any other transition, that involves a change of the conductor width, e.g. between a coaxial connector and a cable. By moving the position of the width step you can almost zero the discontinuity. The effect can be visualized best with a TDR measurement. But for a few GHz range, thé transition isn't that critical, as already mentioned by Azulykit. A single step betweeen the SMA center conductor and the microstrip should be sufficient. If targetting to the high GHz range, you should consider that microstrip is an open transmission line, that produces some dispersion (in the form of radiation losses) anyway.
I am try to construct this transition too and i have many articles about this theme. If you want i can upload some of them.
Can you upload please?
BR
Most of them i will upload later. do you read russian lang?