A new power combiner using aperture coupling technique for push-pull Class B Power Amplifier

A new non-contact feeding technique from a microstrip feed line incorporated with harmonics trap filter to an antenna structure is studied and described. This technique makes practical and effective use of an odd mode signal to generate maximum current under the antenna and efficiently coupled the electromagnetic energy from a microstrip feed line to the antenna via an aperture. In this case, a microstrip feed line is like a power combiner into the antenna´s feed. As for this circuit is co-integrated with Class B Power Amplifier, harmonic trap or bandstop filter (BSF) is essential for harmonic termination within the microstrip feed line. It is to be working in parallel to suppress 2nd and 3rd harmonic respectively and thus, a better output waveform is reshaped. Further mismatch at fundamental (f_o = 2.062 GHz) has occurred when a dual BSF is employed. Hence, a 50Ω line tuning has been done to match the fundamental at its best state. This technique offers advantages of tight and very neat integration for Class B Push-pull amplifier with better antenna performance, well-shaped output waveforms and enhanced immunity from common mode interference.