impedance matching for circularly polarized microstrip patch antenna

Hi... I am new in antenna design I need help regarding impedance matching of transmission line in dual feed circularly polarised microstrip square patch antenna. Please send me design equations and document regarding this. Thanking You in advance....

How did you design the antenna ? If you did it on CST you probably gave waveguide excitation from the ports and your ports are probably Z=50 ohms. When you design antenna , you look at S11 measurements of the antenna.Generally you want your S11 to be below -10dB in band. -10 dB S11 means your VSWR=1.92 and Reflection Coefficient=0.316 . This also means you can have maximum impedance of 96.2 +0j Ohm on your antenna. So If your antenna satisfies S11<-10dB you are good with an 50 ohm SMA or N type connector attached after a 50 ohm microstrip line.

hi,
under the assumption that it is a printed patch then -
you can use this link for the patch design itself:http://www.emtalk.com/mpacalc.php
or https://www.pasternack.com/t-calcula...strip-ant.aspx
and this link for the microstrip line design: Khttp://www.emtalk.com/mscalc.php
for a circular-polarized dual feed patch the patch has to be square (not a rectangle)

regards,
Khttp://www.emtalk.com/mscalc.php