Analysis of negative‐resistance characteristics in active capacitance circuit

Design procedure for active microwave filters using the high quality active negative capacitance circuit for RF low‐noise bandpass applications

“…For the selected applications, alternatives are now emerging that makes use of recent advances in active-filter techniques. Recently, there has been an interest in increasing the performance properties of bandpass filters using different methods [1][2][3][4]. Incase of the increasing the RF technology, active filter transition from passive design become vary fast.…”

“…Incase of the increasing the RF technology, active filter transition from passive design become vary fast. Much research has been performed to achieve broadband characteristics in the design of filters [4][5][6][7]. Among these studies, passive filters with lumped elements have been generally introduced.…”

“…Among these studies, passive filters with lumped elements have been generally introduced. At the same time, it has recently been shown that the gain, return loss, and noise performance properties of active bandpass filters are primarily established by active circuits [4,6,7].…”

“…This perception is not always based on sound reasoning. In the meantime, analyze has been carried out utilizing active circuits in the field where the high-Q filter is demanded [4][5][6]. Active filters, fabricated on planar structure, can provide a high Q property without a high Q resonator [6,8].…”

“…Conventionally, the patch is fed using a perpendicular coaxial probe or a microstrip line connected to the edge [3]. Other elaborate feeding techniques [4,5] with parasitic radiators [6 -8], slots, and various radiator structures are also researched, depending on their applications. Suspended plate antennas (SPAs) achieve the enhanced impedance bandwidth, and reduced undesirable surface wave loss, by replacing the dielectric substrate with air.…”