Need help to solve this antenna radiation patern issue
I am new to this forum and not sure this is the right place to post this.
I want to find out from which side an rfid tag is crossing the RF field.
1)Antenna will generate an RF field.
2)It is circular polarized and connecter in the back side.Assume there is no tag in the field.
3)I want to know how I can find out from which side of the RF field tag is entering.
A very bad iamge is attached with this query.
Please help me
Perara
It depends on where the antenna (coil) is on the tag.
Could you please elaborate about this...I didnt get any clue...
Hi perara,
Better familiarize yourself with EM simulation tools (Such as CST, Ansoft HFSS, Antenna Magus etc). Model your RFID Tag, Analyze the structure. After that plotting fields over the object would give the clear idea..
Hope this helps...
A static EM field strength have no right or left difference, just weaker or stronger field for different space positions and orientation. Compare with a single microphone, from which side comes a recorded sound?
Using two microphones helps a lot but due to local reflections can it still be problem to detect direction. Same for antennas.
If circular polarized antenna and RFID tag is polarized in opposite direction will transmission loss be high but it do not result in a "from which side" related loss.