The recent rapid development in modern communication systems has presented some
constraints caused by the introduced noises, as well as further requirements of low costs
and miniature designs. Such noises are overcome using efficient designs of filtering devices
which are essential components in many satellite, radar and mobile communication
systems. As a result, balanced or differential filtering components have recently received
increasing attention. A wideband microstrip balanced bandpass filter based on modified
stub line approach is presented in here. The proposed idea of extended transmission lines
(TLs) at the input and output (I/O) ports enables for very good stopband rejection and
common-mode suppression.
On the other hand, the recently introduced multilayer liquid crystal polymer (LCP) material
and fabrication technique are exclusively applied in this work for adapting the potential
solutions offered within. Therefore, a comprehensive in-house fabrication process has been
developed and extensively illustrated in this thesis starting from mask preparation covering
the entire procedure up to producing the final piece of output. As a demonstrator of the
potential capability of multilayer LCP technology, a novel miniaturized ultra-wideband
(UWB) balun with self-packaging is introduced in this study. The broadside coupled
stripline structure is adopted in this work to realize UWB performance and TEM mode
which results in excellent amplitude and phase balances.
In turn, a novel compact UWB multilayer balanced bandpass filter using LCP technology is
also presented in this thesis. The design utilizes the transversal signal-interference concept
for realizing an outstanding common-mode suppression while constructed in a stripline
configuration. All of the designs covered in this thesis are initially simulated using CAD
tools to be then validated by measurements of fabricated prototypes
