coaxial cable monopole antenna

HI, does anybody knows how feed a monopole antenna in cst , my design is a flexible antenna and I have the ground in the same plane of the antenna, and I want feed my antenna with a coax cable but I don’t know who to connect the cable between the ground and the signal. I already know how to model the coax cable.

send me the picture i will try to help u..............

Great thanks, I attach the file, I don’t know how to put the port, I am very new in antenna design. I found the design in a book for a 433 MHz but I have a lot of problems
First the simulator give me another frequency up to 433MHz, second I don’t know if the port is correct and I don’t know how to feed the antenna with a coax cable, also I built the antenna but the return loss was -20db at 250MHz and I can’t move it to 433MHz