Impedance matching stripline transition for microwave signals

An impedance matching coaxial transition for microwave signals comprising first and second laminates, at least one intermediate laminate between the first and second laminates, an input conductor from a stripline circuit on the first laminate, an output conductor to a stripline circuit on the second laminate, each of said laminates having a conducting region on one side thereof, a center through-plated hole in each of said first and intermediate laminates, a conducting collar for each hole on each laminate on at least one side of the respective laminate, a plurality of further through plated holes in each of said laminates, the further through-plated holes in the first and intermediate laminates respectively surrounding said center holes therein, each of said further holes being in conducting connection with another hole in said plurality of holes by a first conducting region on one side of the respective laminate and by a second conducting region on the other side of said laminate, said collar and said second conducting region defining a slightly elevated area on the respective side of each laminate, said center through-plated hole in said first laminate forming a first conducting structure together with the corresponding center hole in said intermediate laminate and said elevated area of the respective side of each laminate and defining a conducting connection between said input and output conductors, said plurality of through-plated holes in each of the laminates forming a second conducting structure together with the corresponding plurality of through-plated holes in the other laminates and defining the return conductor of the coaxial transition.