Designing of Hairpin-Line Band Pass filters for DCS, UMTS and LTE-Systems
Abstract: Bandpass filters are
essential components in any wireless systems. They are designed for selecting
desired signal from other signals. Especially in crowded frequency spectrums,
accurate filter characteristics are required to guarantee the performance of
the overall systems. DCS, UMTS and LTE systems are the actual communication
systems used by hundred million users. Bandpass filters designed here is based
on hairpin line structures and implemented in microstrip technology. The
filters are five order Chebychev’s bandpass filters. The center frequency of
each system determines the total length of the U-form hairpin structure. The
design starts with exploiting the coupling between the resonators. The coupling
between two adjacent resonators is determined by the fractional bandwidth of
the system and the element value derived from the Chebychev’s approximation.
The value of the coupling factor leads to the distance between two adjacent
resonators. The simulation results conform to the specifications given in the
standards. In general, the measurements verify the simulation. We see worse
reflection factors and more insertion loss eventually due to bad soldering of
the connectors to the filters. The shifting and width of the pass regions are also
observed, which are probably due to the finite accuracy in prototyping the
filters.
Penulis: Muhammad Sayidi,
Mudrik Alaydrus
Kode Jurnal: jptkomputerdd150488
