Networks using active elements

HELECTRICITY H03Electronic circuits H03HIMPEDANCE NETWORKS

H03H11/00Networks using active elements

H03H11/02Multiple-port networks H03H11/025using current conveyors H03H11/04Frequency selective two-port networks H03H11/0405Non-linear filters H03H11/0416using positive impedance converters H03H11/0422using transconductance amplifiers H03H11/0427Filters using a single transconductance amplifier; Filters derived from a single transconductor filter H03H11/0433Two integrator loop filters H03H11/0438Tow-Thomas biquad H03H11/0444Simulation of ladder networks H03H11/045Leapfrog structures H03H11/0455Multiple integrator loop feedback filters H03H11/0461Current mode filters H03H11/0466Filters combining transconductance amplifiers with other active elements H03H11/0472Current or voltage controlled filters H03H11/06comprising means for compensation of loss H03H11/08using gyrators H03H11/10using negative impedance converters H03H11/11using current conveyors H03H11/12using amplifiers with feedback H03H11/1204Distributed RC filters H03H11/1208comprising an electromechanical resonator H03H11/1213using transistor amplifiers H03H11/1217using a plurality of operational amplifiers H03H11/1221Theory; Synthesis H03H11/1226Filters using operational amplifier poles H03H11/123Modifications to reduce sensitivity H03H11/1234Modifications to reduce detrimental influences of amplifier imperfections H03H11/1239Modifications to reduce influence of variations of temperature H03H11/1243Simulation of ladder networks H03H11/1247Leapfrog structures H03H11/1252Two integrator-loop-filters H03H11/1256Tow-Thomas biquad H03H11/126using a single operational amplifier H03H11/1265Synthesis H03H11/1269Filters using the operational amplifier pole H03H11/1273Modifications to reduce sensitivity H03H11/1278Modifications to reduce detrimental influences of amplifier imperfections H03H11/1282Modifications to reduce influence of variations of temperature H03H11/1286Sallen-Key biquad H03H11/1291Current or voltage controlled filters H03H11/1295Parallel-T filters H03H11/14using electro-optic devices H03H11/16Networks for phase shifting H03H11/18Two-port phase shifters providing a predetermined phase shift H03H11/20Two-port phase shifters providing an adjustable phase shift H03H11/22providing two or more phase shifted output signals H03H11/24Frequency-independent attenuators H03H11/245using field-effect transistor H03H11/26Time-delay networks H03H11/265with adjustable delay H03H11/28Impedance matching networks H03H11/30Automatic matching of source impedance to load impedance H03H11/32Balance-unbalance networks H03H11/34Networks for connecting several sources or loads working on different frequencies or frequency bands, to a common load or source H03H11/342particularly adapted for use in common antenna systems H03H11/344Duplexers H03H11/346particularly adapted as input circuit for receivers H03H11/348particularly adapted as coupling circuit between transmitters and antenna H03H11/36Networks for connecting several sources or loads, working on the same frequency band, to a common load or source H03H11/362particularly adapted for use in common antenna systems H03H11/365particularly adapted as input circuit for receivers H03H11/367particularly adapted as coupling circuit between transmitters and antenna H03H11/38One-way transmission networks H03H11/40Impedance converters H03H11/405Positive impedance converters H03H11/42Gyrators H03H11/44Negative impedance converters H03H11/46One-port networks H03H11/48simulating reactances H03H11/481Simulating capacitances H03H11/483Simulating capacitance multipliers H03H11/485Simulating inductances using operational amplifiers H03H11/486Simulating inductances using transconductance amplifiers H03H11/488Simulating inductances using current conveyors H03H11/50using gyrators H03H11/52simulating negative resistances H03H11/525Simulating frequency dependent negative resistance [FDNR] H03H11/53simulating resistances; simulating resistance multipliers H03H11/54Modifications of networks to reduce influence of variations of temperature