ryhmäantenni

Ryhmäantenni, also known as an antenna array, is a collection of individual antennas that work together to transmit or receive radio waves. The antennas are typically arranged in a specific geometric pattern, such as a line or a grid, and are fed with signals that are phased relative to each other. This phased arrangement is crucial as it allows the combined signal from the array to be steered in a particular direction or to achieve a desired radiation pattern.

The primary advantage of a ryhmäantenni over a single antenna is its ability to control the directionality of the radio waves. By adjusting the phase and amplitude of the signals fed to each individual antenna, the overall beam can be electronically steered without physically moving the antenna. This capability is fundamental to many modern wireless communication systems, radar, and electronic warfare applications.

The performance characteristics of a ryhmäantenni, such as its gain, beamwidth, and side lobe levels, depend on several factors including the number of elements, their spacing, their individual antenna characteristics, and the excitation applied to each element. Larger arrays generally offer higher gain and narrower beamwidths, leading to improved signal reception or transmission range. However, they also come with increased complexity and cost. Different types of ryhmäantennit exist, each suited for specific applications, including linear arrays, planar arrays, and conformal arrays.