DESIGN OF PLANAR MICROSTRIP DIPLEXER

In this report, a microstrip diplexer which has a constant isolation band that can be used for multiple frequency be presented. The proposed structure diplexer using two hairpin filters at the two transmission/ receiver ports which operate in two different frequency bands. The hairpin filter of one of the port be design as a High Pass Filter for the frequency above 2.4 GHz while the other hairpin filter base on low pass filter which allows frequency of 2.4 GHz and below to pass through. The isolation band in this case was 3 MHz between the Band Pass Filter. The proposed circuit should have an insertion loss of less than 2 dBs for both the frequency band and the isolation is proposed to be greater than 30 dBs. The schematic diagram of the diplexer has been stimulated and investigated numerically through the Keysight Advanced Design System. All mathematical calculation will be calculated with MATLAB software. The fabrication of the diplexer will be produced while the result will verify using the Network Analyzer.