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1.Introduction

The HA.31.A is an ISM 915MHz quarter wave-length monopole antenna. This helical

coil antenna is perfect for your smart meter, smart security system, remote asset

monitoring, and other wireless communication devices.

The helical coil antenna has a 2dBi Peak gain and a 68% efficiency at 915MHz on a

126.8 x 80.1mm ground plane with matching components (orthogonally mounted to

ground plane, see HAD.B.31 performance).

Made of copper alloy, the helical coil is mechanically sturdy, with a wide-bandwidth. It

can be easily mounted on the surface of your device main board by soldering. The

antenna must be connected to a ground-plane to radiate efficiently.