Ultra wideband planar triangular patch antenna with slit ridged ground plane

One of the problems in wireless communication is the availability of frequency spectrum. Currently, the number of frequency bands allocated for telecommunications is very wide. However, the use of the frequency band is not evenly distributed, there is a frequency band that users are too crowded, while others are still rare. This has encouraged the use of cognitive radio (CR). CR is a device that is able to sense and detect the unused frequency spectrum and simultaneously acquired these frequencies for communication.