Q on defining lumped port value on HFSS RFID tag design

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komplz

Joined: 06 Mar 2009
Posts: 2

02 Nov 2009 15:13 Q on defining lumped port value on HFSS RFID tag design

I am using HFSS to design a passive RFID Tag Antenna.
I'm using a microchip with impedance 16-j380 and, therefore,I have to design a RFID tag with 16+j380 to get the impedance matching with the microship. When I define a lumped port in my design, I have to enter the resistance and reactance value of the lumped port. My question is that Should I enter the impedance value of the microchip (16 and -380) or I should enter the value that I desired (16 and +380)?

I tried using both the values to obtain the simulation results. I get positive S11 value, which is impossible for an passive RFID tag, if I use 16 and -380. While using 16 and +380, I got negative S11 value. Both simulation results get the same impedance matching values.