Hello.
I am having trouble getting info about the UHFC RFID Antenna (WRL-14131) in regards of its lobe (read expansion), as it may be confusing, let me explain my goal:
I am trying to build a embedded system for my university library, and may need to put an antenna in the exit (about 3m tall, 1m wide) for detecting the tags inside the library books (kind of an anti-theft), but as I can see the antenna is just 20cm x 22.3cm (about 5 times smaller than the exit) but I was wondering if the beam is expanded or how is its lobe defined (couldn’t find info about it in the datasheet)
I would also like to know if the antenna is capable enough to detect tags inside the books in the desired distance (2-3m above the possible reading position)
Thanks!
Hi josedanield10,
The [UHF RFID Antenna has a vertical linear polarity so the waveform will propagate directly outward along a vertical pole from the antenna. [This quick tutorial goes into a bit more detail about antenna polarization.
As for detecting tags inside of a book, it’s impossible to tell for certain but your read distance will absolutely be affected by interference caused by the books and a person carrying them. It is just something that would need to be tested to determine the ideal placement of both tag and antenna as well as other settings (eg. read power etc.). The [Range Test Example from the Hookup Guide will go over antenna/tag alignment and the other factors that cause interference.](https://learn.sparkfun.com/tutorials/simultaneous-rfid-tag-reader-hookup-guide/example-10---range-test)](Understanding Antenna Polarization - everything RF)](https://www.sparkfun.com/products/14131)