How many antennas are utilized in a four beam Janus array?

In a four beam Janus array, there are indeed four antennas utilized. This design allows for the simultaneous transmission and reception of signals in multiple directions, effectively creating four distinct beam patterns. Each of the antennas in the array contributes to the formation of these beams, which can be directed independently to cover a wider area or to enhance detection capabilities.

The design is particularly useful in radar applications, where having multiple beams allows for better coverage and more efficient data collection, especially in complex environments. The arrangement promotes beaconing and scanning capabilities, enhancing target detection and tracking efficiency. Therefore, the use of four antennas is critical in achieving the desired operational performance of the Janus array.