What effect does increasing the length of an antenna have on its resonant frequency?

Increasing the length of an antenna results in a lower resonant frequency due to the relationship between an antenna's physical length and its operating frequency. The resonant frequency is inversely proportional to the length of the antenna; as the length increases, the resonant frequency decreases. This is based on the principle that longer antennas effectively interact with longer wavelengths, which correspond to lower frequencies.

In practical terms, when you lengthen an antenna, it becomes capable of efficiently radiating or receiving signals at lower frequencies. This concept is critical in antenna design, particularly for applications such as radio transmission and reception, where matching the antenna's length to the desired operating frequency is essential for optimal performance. Understanding this relationship helps technicians make informed decisions regarding antenna sizes for specific frequency bands.