Design of 24 GHz Antenna Array for Powder Materials Flow Measurement Applications

This article proposes a pair of 1×4 antenna array in 24 GHz-24.25 GHz (ISM band) for transmitting and receiving. It has good isolation less than -30 dB in the operating frequency band. And the measured gain is as high as 8.9 dBi. The size is only 20 mm*20 mm. With Doppler radar module, it is used to sense the flow of powder, which can reach a measured distance of 1.5 m. The 1×4 antenna array be fed uses an equal power network. Rogers RO4003C glass fiber substrate is used for the milli-meter wave frequency band. It has a low dielectric constant of 3.55 and a low dielectric loss of 0.0027.