Recently, I have received an antenna from one of the Chinese manufacturer and they haven't disclosed the detailed specification with us.
Below is the picture of my antenna (please ignore the specification in the picture):
The specification that are provided by the vendor are over here.
- Frequency: 865-867 MHz
- Gain: 3dBi
- VSWR < 3.0 : 1
- Radiation Pattern: Omnidirectional
- Impedance: 50 ohm
- Length (From connector to Antenna End): 500mm
I want to know from it's size and gain, Can we predict it's antenna type (e.g. Collinear antenna), it's design (dipole or mono-pole), internal construction, polarization and various other parameters?
These kinds of antennas look to be standard and I think others who have used them in the past can help me in identifying my own antennas. I am waiting for my manufacturer to share detailed specification but I am not sure how long will they take.
According to my calculations, the wavelength for 865 MHz signal would be
0.346580 meters. So, for half-wave dipole, the length should be
0.17329 meter. However, length of my antennas is bigger than that. I think that's why it is
collinear dipole array antenna. Please correct me if I am wrong.