Microstrip and HMSIW six-port junctions designs and comparison

In this paper, micro-strip, SIW and HMSIW couplers operating at a center frequency of 2.45 GHz were presented and compared. Simulations of the three couplers were presented over a frequency band from 1.8 GHz to 3.2 GHz. Compared to the micro-strip coupler, the SIW one is characterized by low lost and high Q value but it suffers from the big size in low frequency band, So to realize a nearly 50% reduction in size with keeping the good performances of the SIW technology, half mode substrate integrated wave guide HMSIW origins from SIW has been used. A novel structure of a six-port junction based on HMSIW technology was designed with a low cost FR4 substrate and compared to a conventional six-port junction based on micro-strip technology. Good performances were achieved with our proposed HMSIW six-port junction.