I bought a GSM antenna from AliExpress. According to the specifications, it should work properly at 900 MHz But when I tested it on the nanoVNA. I got strange results:
Firstly, its impedance was never 50ohm, and
Secondly, its 900 MHz band was shifted to approximately 1 GHz. (Highlighted Yellow)
I have taken these reading at IPX end of the antenna (see below for Antenna Picture) . My nanoVNA was fully calibrated.
My question is why am I getting wrong results ?
Firstly, its impedance was never 50ohm, and
Secondly, its 900 MHz band was shifted to approximately 1 GHz. (Highlighted Yellow)
I have taken these reading at IPX end of the antenna (see below for Antenna Picture) . My nanoVNA was fully calibrated.
My question is why am I getting wrong results ?
