Sherry1
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Hi I made a 2 layer FR4 PCB for the chip antenna. One end of the 50 Ohm feed line starts from antenna pads, the other end of the feed line goes to SMA connector. The width is calculated using coplanar waveguide with ground calculator.
when i use VNA and find out the impedance and add matching network, the S11 only gets worse.
Sometimes impedance comes like (say) 65+j45 and so I have to manually break the trace and put capacitor in series to introduce -45j reactance. But breaking the trace itself changes everything.
Any suggestions how do i match the 50 ohms feed line to the antenna ?
Shall I use balun? or Shall i print broken feed trace?
when i use VNA and find out the impedance and add matching network, the S11 only gets worse.
Sometimes impedance comes like (say) 65+j45 and so I have to manually break the trace and put capacitor in series to introduce -45j reactance. But breaking the trace itself changes everything.
Any suggestions how do i match the 50 ohms feed line to the antenna ?
Shall I use balun? or Shall i print broken feed trace?