Wideband beam forming network for simple scanning arrays

In this work, a C-band passive microstrip 4-element antenna array beam forming network (BFN) using high-directivity directional couplers is employed (in the transmit mode) to split a signal into four equiphase equiamplitude parts so as to correctly feed the elements of a linear/2-D array. Amplitude difference between the four feeds is within 0.5 dB and the phases of the signals at the feeds differ by less than 10° in a 4:1 bandwidth