Hawkeye 5.8G 7.5dBi - 152mm Linear SMA

Hawkeye 5.8G 7.5dBi is an omnidirectional antenna with linear polarization, an SMA connector, and 7.5dBi gain for the 5-6GHz band. The manufacturer specifies it for fixed-wing aircraft (“fixed wing”), where it is mounted vertically above the fuselage. The gain is high for an omnidirectional antenna – radiation is concentrated in the horizontal plane, and the main lobe is only 29.4° wide (3dB drop). The signal is therefore directed mainly to the sides, toward a model flying along the course, while it is weaker directly above and below the antenna.

Linear polarization requires antennas on both sides of the transmission to have the same orientation – therefore, the manufacturer specifies mounting it perpendicular to the ground. Combining circular and linear polarized antennas results in a 3dB loss. The 5-6GHz band, centered at 5.5GHz, covers standard 5.8GHz FPV channels as well as lower frequencies around 5GHz. VSWR (voltage standing wave ratio, indicating how much power is reflected from the antenna back to the transmitter) is no more than 1.8.

The antenna is a black flat rod measuring 152x22x7mm, with a hinge at the connector, and weighs 19g. For airplanes, the manufacturer recommends a pair of antennas: both perpendicular to the ground, parallel to each other, and extending at least 10cm above the fuselage so that nothing obstructs them.