Understanding Antenna Specifications and Operation

The antenna is probably the most overlooked part of an RF design. The range, performance, and legality of an RF link are critically dependent upon the antenna. However, it is often left until the end of the design and expected to fit into whatever space is left, no matter how unfavorable to performance that location may be. Many of these designs will have to ultimately accept degraded performance or go through multiple redesigns.

This article will focus only on those styles which are commonly used in low-power handheld products: dipole and monopole whips. These styles cover a wide range of available antennas and are among the most common to be implemented incorrectly. With that in mind, there are several rules of thumb that can be applied to antenna designs. These rules are less “how to design an antenna” and more “how to design with an antenna.”