User Manual

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RC220x
 2005 Radiocrafts AS RC220x Data Sheet (rev. 1.0) Page 12 of 17
The simplest antenna to use is the quarter wave whip antenna. A quarter wave whip antenna
above a ground plane yields 37 Ohm impedance and a matching circuit for 50 Ohm are
usually not required.
A PCB antenna can be made as a copper track where the ground plane is removed on the
back side. The rest of the PCB board should have a ground plane as large as possible,
preferably as large as the antenna itself, to make it act as a counterweight to the antenna. If
the track is shorter than a quarter of a wavelength, the antenna should be matched to 50
ohms.
The length of a quarter wave antenna is 2.9 cm at 2450 MHz.