A
sensor array is a group of sensors, usually deployed in a certain geometry pattern, used for collecting and processing electromagnetic or acoustic signals. The advantage of using a sensor array over using a single sensor lies in the fact that an array adds new dimensions to the observation, helping to estimate more parameters and improve the estimation performance. For example an array of radio antenna elements used for beamforming can increase
antenna gain in the direction of the signal while decreasing the gain in other directions, i.e., increasing
signal-to-noise ratio (
SNR) by amplifying the signal coherently. Another example of sensor array application is to estimate the
direction of arrival of impinging electromagnetic waves. The related processing method is called
Array Signal Processing. Application examples of array signal processing include
radar/
sonar, wireless communications,
seismology, machine condition monitoring, astronomical observations
fault diagnosis, etc.