发明名称 |
Monolithischer HBT aktives abstimmbares Bandpassfilter |
摘要 |
An active tuneable band-pass filter is provided which has a negative resistance circuit for generating a tuneable amount of negative resistance for a passive band-pass filter structure so as to compensate for resistive losses. The negative resistance circuit has a bipolar transistor with a base connected in shunt to the passive filter structure and a collector connected to a shunt inductive element. A negative resistance is generated at the base of the transistor and is applied to the passive filter structure. A coarse Q-factor tuning circuit is coupled to the emitter of the transistor for providing a coarse amount of tuning of the negative resistance. Also connected to the emitter terminal, is a fine tuning circuit for providing fine tuning of the negative resistance. The fine tuning may be achieved manually or automatically with a control circuit. The coarse and fine tuning capability provides a tuneable negative resistance which eliminates oscillations and compensates for resistive loss variations to realize improved q-factor. |
申请公布号 |
DE69628611(T2) |
申请公布日期 |
2004.04.15 |
申请号 |
DE1996628611T |
申请日期 |
1996.03.20 |
申请人 |
NORTHROP GRUMMAN CORP. (N.D.GES.D.STAATES DELAWARE), LOS ANGELES |
发明人 |
KOBAYASHI, KEVIN W. |
分类号 |
H03H11/04;H03H11/06;H03H11/10;H03H11/52 |
主分类号 |
H03H11/04 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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