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`Samsung Electronics Co., Ltd. v. Demaray LLC
`Samsung Electronic's Exhibit 1058
`Exhibit 1058, Page 1
`
`

`

`
`
`
`
`
`U.S. Patent
`
`
`
`
`
`
`
` J0UN0S
`
`
`Sep. 15, 1992
`
`
`
`WNOIS
`
`Sheet 1 of 9
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`
`
`5,148,133
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`
`
`Ex. 1058, Page 2
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`Ex. 1058, Page 2
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`
`

`

`
`
`YOLINON
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`
`U.S. Patent
`
`
`
`
`
`
`Sep. 15, 1992
`
`Sheet 2 of 9
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`
`
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`5,148,133
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`
`
`Ex. 1058, Page 3
`
`Ex. 1058, Page 3
`
`

`

`
`U.S. Patent
`
`
`
`
`
`Sep. 15, 1992
`
`
`
`Sheet 3 of 9
`
`
`
`
`
`
`YOLINOW
`
`WNOIS
`
`JOUNOS
`
`5,148,133
`
`
`
`Ex. 1058, Page 4
`
`Ex. 1058, Page 4
`
`

`

`
`U.S. Patent
`
`
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`
`
`
`
`
`
`
`Sep. 15, 1992
`
`
`
`Sheet 4 of 9
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`5,148,133
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`
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`Ex. 1058, Page 5
`
`Ex. 1058, Page 5
`
`

`

`
`U.S. Patent
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`
`
`
`
`
`Sep. 15, 1992
`
`
`
`"Sheet 5 of 9
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`5,148,133
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`
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`Ex. 1058, Page 6
`
`Ex. 1058, Page 6
`
`

`

`
`U.S. Patent
`
`
`
`
`
`Sep. 15, 1992
`
`
`
`Sheet 6 of 9
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`5,148,133
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`Ex. 1058, Page 7
`
`Ex. 1058, Page 7
`
`

`

`
`U.S. Patent
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`
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`
`
`Sep. 15, 1992
`
`
`
`Sheet 7 of 9
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`5,148,133
`
`
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`
`Yi
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`
`
`Ya:INSC}LY22-7IAyONNemeth
`arene‘AAAAaAa|ETLTEE5EDOPOEAEATSEAA:mlitacca
`
`anPoatHeSCoy
`
`
`
`
`
`
`Ex. 1058, Page 8
`
`Ex. 1058, Page 8
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`

`

`
`U.S. Patent
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`
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`
`Sep. 15, 1992
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`
`
`Sheet 8 of 9
`
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`5,148,133
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`
`
`
`
`ZHWOOGINVdS~
`
`9asulQOLdMS
`
`ZHAOlM&A
`apOlNALLYwapO°
`
`ZHO!|MA‘Say
`ZHWOS'60E=YALN3D
`
`
`
`Ex. 1058, Page 9
`
`
`
`dau
`
`
`
`—on
`
`
`
`—eeee
`/aPol
`
`O1puz
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`
`
`b~BI4
`
`Ex. 1058, Page 9
`
`

`

`
`U.S. Patent
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`
`
`Sep. 15, 1992
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`
`
`Sheet 9 of 9
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`LuvYOldG“big
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`5,148,133
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`Ex. 1058, Page 10
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`Ex. 1058, Page 10
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`

`

`1
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`5,148,133
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`15
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`35
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`QUALITY FACTOR IMPROVEMENT FOR FILTER
`APPLICATIONS
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`2
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`diameter wire. In decoding and descrambling applica-
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`tions, however, the Q cannot be improved byutilizing
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`larger coils due to the above-described size and corre-
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`sponding layoutrestrictions.
`FIELD OF THE INVENTION
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`In view of the above,it is an object of the invention
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`to provide a highly reliable, narrow and stable notch
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`The invention relates in general to tuned filters. More
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`filter having a high Q while minimizing the overall size
`specifically, the invention relates to tuned filters, such
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`of the notch filter. Further objects, features and advan-
`as notch filters, which are particularly well suited for
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`tages of the invention will become apparent from the
`use in removing single or multiple frequency scram-
`10
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`ensuing detailed description of the preferred embodi-
`bling signals injected into a communication signal to
`ment of the invention taken in connection with the
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`eliminate the possibility of intelligible reception of
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`accompanying drawings
`video and/or audio information, or for use in removing
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`a video carrier in a television channel to prevent its
`SUMMARY OF THE INVENTION
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`reception.
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`Thepresent invention is based on the recognition that
`BACKGROUNDOF THE INVENTION
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`the Q of a tuned filter can be improved, while minimiz-
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`It has long been a customarypractice for subscription
`ing the overall size of the filter to within restricted
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`television communication systems—a system in which
`cavity size limitations, by replacing single inductors and
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`the reception of a television program signal, generally
`capacitors in conventionalfilter structures with parallel
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`recoverable by a groupoftelevision receivers,is limited
`multiple inductors and/or multiple series capacitors as
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`to specifically authorized receivers—to scramble or
`required.
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`encode their television transmission signals to prevent
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`Morespecifically, in a preferred embodiment of the
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`unauthorized reception by individuals who have not
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`invention, a tuned filter is provided that includes an
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`paid a subscription fee. Conventional hard-wired com-
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`input terminal and an output terminal; a first network
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`munity antenna television systems (CATV), for exam-
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`coupled to the input
`termina] and electrical ground
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`ple, are representative of a typical subscription televi-
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`including a plurality of series capacitors and/or a plu-
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`sion communication system, although other systems
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`rality of parallel inductors; and a second network cou-
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`have been developed that employ radio frequency (RF)
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`pled to the input terminal and the output terminal in-.
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`transmission to subscribers instead of hard-wiring.If the
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`cluding at least one of a plurality of series capacitors
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`subscription television system provides more than one
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`and/or a plurality of parallel inductors. The Q of the
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`channel,it is also desirable to provide selected scram-
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`filter is improved by the use of the series capacitors
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`bling or securing of individual channels that are used to
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`and/or parallel inductors opposed to single capacitors
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`provide premium services.
`or inductors.
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`One of the methods most commonly employed to
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`BRIEF DESCRIPTION OF THE DRAWINGS
`prevent unauthorized reception to add a scrambling
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`signal or interfering carrier signal
`to the television
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`With the above as background, reference should now
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`transmission signa] betweenits aural and visual carriers.
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`be made to the detailed description of the preferred
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`The scrambling signal is added to the television trans-
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`embodiment of the invention and the accompanying
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`mission signal to provide additional information which
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`40
`drawings in which:
`causes a television receiver to reconstitute the scram-
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`FIGS. la-1e are an electrical schematic diagrams of
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`bled television transmission signal
`in an incoherent
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`filters in accordance with the invention;
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`form. The scrambling signal is removed by passing the
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`FIG.2 is a top plan view of a notchfilter constructed
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`scrambled television transmission signal
`through a
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`on a circuit board in accordance with the invention;
`tuned notchfilter at the site of an authorized television
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`45
`receiver.
`FIG.3 is a sectional side view through a notchfilter
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`of the type illustrated in FIG. 2 and accompanying
`Tuned notchfilters to be utilized in the video/audio
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`housing;
`frequency removal or descrambling process must meet
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`FIG.4 is a data plot of a notch filter in accordance
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`several critical requirements. For example,it is critical
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`with the present invention overlaid on a data plot of a
`that the tuned notchfilter have a high degreeofstability
`50
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`conventional notchfilter; and
`and reliability. In addition, the size of the notch filter
`FIG.§ is a schematic of a conventional notchfilter.
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`must remain small, preferably less than 0.825 inch diam-
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`eter, to enable the notch filter to be utilized in typical
`DETAILED DESCRIPTION OF THE
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`installations where one or morefilters are mounted on a
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`PREFERRED EMBODIMENT
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`directional tap on a strand, in a pedestal, or some other
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`Referring first to FIG. 5, an electrical schematic
`small enclosure. The notchfilter must also be capable of
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`diagram of a conventional notch filter of the general
`a large degree of attenuation at the center frequency of
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`type described in U.S. Pat. No. 4,451,803 is shown. An
`the notch with very sharp skirts and a narrow band-
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`input terminal 8 is provided to receive an incoming
`width to minimize unwanted attenuation of adjacent
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`communication signal, such as a television signal, in-
`channels. As the frequency requirements increase,
`60
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`cluding one or moresignals which are to be removed
`sharperskirts are required to maintain the desired band-
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`(attenuated) by the notchfilter. Input terminal 8 is con-
`width while minimizing interference with adjacent
`channels.
`.
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`nected to one terminal of capacitor C5 and the other
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`terminal of capacitor C5 is connected to one terminal of
`In order to achieve sharper skirts, the notch filter
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`a parallel arrangement of a capacitor C2 and an induc-
`must have a high Q (Quality Factor), i.e., the bandwidth
`65 tor L2. The other terminal of the parallel arrangement
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`is minimized by optimization of the Q of the notch
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`of capacitor C2 and inductor L2 is connected to a
`filters’ inductors and capacitors. In most applications,
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`ground conductor. Terminal 8 is also connected to one
`the Q ofthe notch filter can be improved byutilizing
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`terminal of an inductor L8 in parallel with a network
`inductors having larger winding diameters with larger
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`Ex. 1058, Page 11
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`Ex. 1058, Page 11
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`

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`3
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`consisting of capacitor Cl in series with an inductor L1.
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`The other terminal of the network passesinto an isola-
`tion area 4 and is connected to one terminal of a cou-
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`pling capacitor C9. The circuitry described thus far,
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`prior to the coupling capacitor C9, forms one filtering
`section 15.
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`The other terminal of capacitor C9 connects into
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`filtering section 14 of the notchfilter to one terminal of
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`an inductor L11 which is connected in parallel with a
`10
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`network consisting of inductor L4 in series with a ca-
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`pacitor C4. The other terminal of this network is con-
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`_hected to the output terminal 9. Output terminal 9 is
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`also connected to one terminal! of capacitor C8 whichin
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`turn is connected at its other terminal to a parallel ar-
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`rangementofa capacitor C3 and inductor L3. Remain-
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`ing television signals exit through terminal9.
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`The invention is based on the recognition that two or
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`moreinductors ofthe proper values can be connectedin
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`parallel to obtain a desired inductance with a Q thatis
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`greater than the Q for a single inductorof the equivalent
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`inductance, and/or two or more capacitors of the
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`proper values can be connected in series to obtain a
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`desired capacitance with a Q which is greater than the
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`Q for a single capacitor of equivalent capacitance in
`25
`several areas of the conventional notchfilter illustrated
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`in FIG. 5. Having discovered this advantageouseffect,
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`our subsequent mathematical analyses confirmed that
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`the utilization of two or more inductors or capacitors to
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`replace a single inductor or capacitor can improve the
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`Q of the overall notchfilter:
`Case 1
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`Two equal coils to equal one coil of half inductance
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`where Lo=0.0258 pH is the desired inductance and
`f= 100 MHz.
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`The desired inductance can be achieved with one
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`0.125" diameter coil having 2.5 turns using 24 Gauge
`wire. The calculated theoretical value for this coil is
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`Lo=0.0258 pH with Qo=337.8@100 MHz.
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`Knowing that two coils in parallel add per the fol-
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`lowing:
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`Lo=(Z1714.L274)7!
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`30
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`35
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`For two equal coils, it can be determined that:
`£;=L2=0.0514 [uH
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`45
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`This desired inductance for two equal coils can. be
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`achieved with 0.119” diameter coils having 4.5 turns
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`using 22 Gauge wire. The calculated theoretical value
`for these coils is:
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`L;=L2=0.0514 pH with Q) =)=473.7@100 MHZ
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`X11=X1L2=jwLl=j27f/L} =/32.3@100 MHZ
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`
`55
`
`
`
`Roi =R1L2=2411/0) =32.3/473.7=0.0682 2
`
`
`
`Since;
`
`
`
`Zp=RLtXzL
`
`and;
`
`
`
`Zro=(Z117'4+Z227)-!
`
`then
`
`
`
`Rro+X1o=(Ri1+X11)714(Rr24- X12)- 7!
`
`65
`
`
`
`5,148,133
`
`
`
`4
`
`
`
`Ryo+Xz9= 0.03409 +/16.15
`
`Qo=X10/RL9=16.15/0.03409 = 473.7
`
`Lo=Xo/jw=16.15/27f=0.0257 pH
`
`15
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Thus,
`the resulting inductance of the two coils
`
`
`
`
`
`
`
`(0.0257 pH) is the same as the inductanceofthe single
`
`
`
`
`
`
`
`
`coil (0.0258 wH) if the round-off errors are taken into
`
`
`
`
`
`account. The Q of the two coils (473.7) is significantly
`
`
`
`
`
`
`improved, however, over the Q of the single coil
`
`(337.8).
`
`
`
`
`
`
`
`Case 2
`
`
`
`
`
`
`
`
`
`Two unequal coils to equal one coil of less inductance
`
`
`
`
`
`if the desired inductance is L,=0.0435 pH and f=100
`MHz.
`
`The desired inductance can be achieved with one
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`0.180" diameter coil having 2.5 turns using 26 Gauge
`wire. The calculated theoretical value for this coil is
`
`
`
`
`
`
`
`
`
`
`
`
`L,=0.0435 nH with Q,=333.1@100 MHz.
`
`
`
`
`
`
`
`
`Arbitrarily picking one coil to be a 7.5 turn, 0.180”
`
`
`
`
`
`
`
`
`
`diameter coil using 26 Gauge wire, the other coil needs
`
`
`
`
`
`
`
`
`to be a 5.5 turn, 0.096” diameter coil using 24 Gauge
`
`
`
`
`
`
`
`
`wire. The resulting inductance and Q,for these coils, is
`as follows:
`
`
`
`Ly =0.2264 pH with OQ, =577.4@100 MHZ
`
`
`12=0.0539 pH with Q)=399.7@100 MHZ
`
`
`
`
`
`
`
`
`
`
`
`Calculating the. resistances, impedances, and resultant
`
`
`
`
`
`
`inductance and Q, as in Case 1, give the following re-
`sults:
`
`
`
`
`Lo=0.0436 pH with Qp=424.9@100 MHZ
`
`
`
`
`
`
`
`
`
`
`
`
`Theresulting inductanceof the twocoils (0.0436 1H)is
`
`
`
`
`
`
`
`
`
`the sameas the inductanceofthe single coil (0.435 »H)
`
`
`
`
`
`
`
`
`
`if the round-off errors are taken into account. The Q of
`
`
`
`
`
`
`
`
`the two coils (424.9) is significantly improved over the
`
`
`
`
`
`Q of the single coil (333.1).
`Case 3
`
`
`
`
`
`
`
`
`Two capacitors to equal one capacitor ofless capaci-
`tance.
`
`
`
`
`
`
`
`
`
`Using a similar analysis to Case 1 and Case 2, an
`
`
`
`
`
`
`improvement, in Q, can be shown for two capacitors
`
`
`
`
`
`
`used in a series configuration where C,=1.0 pF is the
`
`
`
`
`desired capacitance and f= 100 MHz.
`
`
`
`
`
`
`
`The desired capacitance can be achieved with one 1.0
`
`
`
`
`
`
`
`
`pF capacitor which has‘a Q of 2420. Thesingle capaci-
`
`
`
`
`
`
`tor can be replaced by two 2.0 pF capacitors in series
`
`
`
`
`
`
`
`which have a resultant capacitance of 1.0 pF and a
`
`
`
`
`
`resultant Q of =440, or by a 1.5 pF capacitor in series
`
`
`
`
`
`
`
`with a 3.0 pF capacitor which have a resultant capaci-
`
`
`
`
`
`tance of 1.0 pF and a resultant Q of 2439.56. In both
`
`
`
`
`
`
`examples, the resultant capacitance was 1.0 pF, as de-
`
`
`
`
`
`
`sired, and an improvement in Q from 420 to approxi-
`
`
`
`
`
`
`
`
`mately 440 was shown over a single capacitor of the
`
`
`same capacitance.
`,
`
`
`
`
`
`
`
`Referring now to FIG. 1a, an electrical schematic
`
`
`
`
`
`
`
`diagram ofa notch filter in accordance with the inven-
`
`
`
`
`
`
`tion is illustrated. A prime notation (’) will be used to
`
`
`
`
`
`
`indicate components which correspond to the compo-
`
`
`
`
`
`
`
`nents of the conventional notchfilter illustrated in FIG.
`
`
`
`
`
`
`
`
`5. The notch filter shown in FIG. 1 includes an input
`
`
`
`
`
`
`terminal 8' that is coupled to a television signal source
`
`
`
`
`
`
`
`
`to receive an input signal. The input terminal 8’ is con-
`
`
`
`
`
`
`nected to one terminal of a network including multiple
`
`Ex. 1058, Page 12
`
`Ex. 1058, Page 12
`
`

`

`5,148,133
`
`15
`
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`
`25
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`5
`
`
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`capacitors C15 and C6 which are connected in a series
`
`
`
`
`
`
`configuration which gives them an increased Q as con-
`
`
`
`
`
`
`
`firmed by the calculations provided above. The capaci-
`
`
`
`
`
`tor C6 is connected to a parallel arrangement of a ca-
`
`
`
`
`
`
`
`
`
`pacitor C2’ and multiple inductors L12 and L9. The
`
`
`
`
`
`
`inductors L12 and L9 are placed in a parallel configura-
`
`
`
`
`
`
`tion to increase the Q as described by the calculations
`
`
`
`
`
`
`
`
`provided above. The other terminal of the network
`
`
`
`
`
`
`
`including capacitor C2’ and inductors L12 and L9 is
`10
`
`
`
`
`
`connected to a ground conductor. Terminal 8’ is also
`
`
`
`
`
`connected to one terminal of a network consisting of
`
`
`
`
`
`
`
`inductors L7 and L18, arranged in parallel for an im-
`
`
`
`
`
`provementin Q,in parallel with a network consisting of
`
`
`
`
`
`
`
`capacitor Cl’ whichis in series with multiple inductors
`
`
`
`
`
`
`L11 and LS arrangedin parallel for an improvementin
`
`
`
`
`
`
`
`
`
`Q. The circuit described thus far forms onefiltering
`section 15’ of the overall notch filter illustrated in FIG.
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`1. The filtering section 15’, specifically the network
`
`
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`
`
`
`
`
`including the multiple parallel inductors L18 and L7
`
`
`
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`
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`
`
`and the network including capacitor C1’ in series with
`
`
`
`
`
`
`parallel inductors L11 and LS is connected to a cou-
`
`
`
`
`
`
`
`pling capacitor C9’ of an isolation area 4’. An optional
`
`
`
`
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`
`
`capacitor C31 coupled between the network and
`
`
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`
`
`
`
`ground mayalso be utilized to improve high frequency
`response.
`
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`
`
`The other terminal of capacitor C9’ connects into
`
`
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`
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`filtering section 14’ to one terminal of a network (a
`
`
`
`
`
`
`
`capacitor C32 may also be provided as shownto im-
`
`
`
`
`
`
`prove high frequency response), consisting of multiple
`
`
`
`
`
`
`
`
`inductors L22 and L21, connected in parallel for an
`
`
`
`
`
`improvementin Q, whicharein parallel with a terminal
`
`
`
`
`
`
`
`of a network consisting of multiple inductors L14 and
`
`
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`
`
`L6, connected in parallel for an improvementin Q,in
`
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`
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`
`
`
`
`series with a capacitor C4’. The other terminal of this
`
`
`
`
`
`
`network is connected to the output terminal 9’. Output
`terminal 9’ is also connected to a terminal of a network
`
`
`
`
`
`
`
`
`
`
`
`
`including multiple capacitors C18 and C7 which are
`
`
`
`
`
`
`connected in a series configuration to give them an
`
`
`
`
`
`increased Q. Capacitor C7 is connected to a parallel
`40
`
`
`
`
`
`
`
`arrangementof a capacitor C3’ and inductors L13 and
`
`
`
`
`
`
`
`
`L10. The inductors L13 and L10 are arranged in a par-
`
`
`
`
`
`
`
`allel configuration to increase the Q. The other terminal
`
`
`
`
`
`
`
`
`of the parallel arrangement of capacitor C3’ and induc-
`
`
`
`
`
`
`
`tors L13 and L10 is connected to a ground conductor.
`45
`
`
`
`
`
`
`
`output terminal 9’ and are supplied to a customer drop
`
`
`
`
`
`
`
`coupled to the output terminal 9’. The customer dropis
`then connected to a television monitor.
`
`
`
`
`
`
`
`
`
`
`
`
`FIG.1a thus showstwoseparatefiltering sections 15’
`
`
`
`
`
`
`and 14’ which correspond to the filtering sections 15
`and 14 of the conventional notch filter illustrated in
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`FIG. 5. The first filtering section 15’ exists between
`
`
`
`
`
`
`
`
`input terminal 8’ and isolation area 4’ and the second
`
`
`
`
`
`
`
`filtering section 14’ exists betweenisolation area 4’ and
`
`
`
`
`
`
`
`output terminal 9’. The components of the filtering
`
`
`
`
`
`
`
`
`
`sections 14’ and 15’ and the isolation area 4’ are physi-
`
`
`
`
`
`
`cally arranged on a circuit board as shownin FIG. 2.
`
`
`
`
`
`
`Thecircuit board is placed within a housing as shownin
`FIG.3.
`
`
`
`
`
`
`
`
`In the preferred embodiment of the invention illus-
`60
`
`
`
`
`
`
`
`
`
`
`trated in FIG. 1a, the inductors L2, L3, L8,L1, L11 and
`L4 of the conventional notchfilter illustrated in FIG. 5
`
`
`
`
`
`
`
`
`
`
`
`were replaced by the parallel arrangements of inductors
`
`
`
`
`
`
`
`
`
`
`(L12, L9), (L13, L10), (L18, L7), (L114, LS), (L21, £22)
`
`
`
`
`
`
`
`and (L14, L6), respectively, to improve the overall Q of
`65
`
`
`
`
`
`
`
`the notch filter. Similarly, the capacitors C5 and C8 of
`
`
`
`
`
`
`
`the conventional notch filter were replaced by the series
`
`
`
`
`
`
`
`
`capacitors (C15, C6) and (C18, C7), respectively, to
`
`
`
`
`
`
`improve the overall Q of the notchfilter.
`
`50
`
`
`
`6
`
`
`
`
`
`
`
`
`
`A further benefit of the invention is the ability to
`
`
`
`
`
`
`
`
`
`adjust or tune L11, L12, L13, and 114 to a natural pitch
`
`
`
`
`
`
`configuration, which in practice improves the Q. Natu-
`
`
`
`
`
`
`
`
`ral pitch is the condition wherea coil is positioned such
`
`
`
`
`
`
`
`
`
`that the space between adjacent turnsis the same as the
`
`
`
`
`
`
`
`
`
`wire diameter. In previous designs of the type illus-
`
`
`
`
`
`
`
`
`trated in FIG. 5, the coils were designed for a natural
`
`
`
`
`
`
`pitch condition, but component tolerances sometimes
`
`
`
`
`
`
`
`madeit necessary to compressorstretch the coils from
`
`
`
`
`
`
`
`a natural pitch condition to compensate for tolerances.
`
`
`
`
`
`
`
`
`
`The coil windings and spaces for the preferred embodi-
`ment of the invention are shown on FIG.3 as indicated
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`by L11, L12, L413, and L14. Since parallel coils exist to
`
`
`
`
`
`
`
`
`obtain the desired inductance value, the inductors L11,
`
`
`
`
`
`
`
`
`
`L12, L13, and L14 can be positioned for a natural pitch
`
`
`
`
`
`
`condition and tolerances can be compensated for by
`
`
`
`
`
`
`
`stretching or compressing L5, L6, L9, and L10.
`
`
`
`
`
`
`FIG. 4 shows the difference in performance of a
`
`
`
`
`
`
`
`conventional tuned notchfilter of the type illustrated in
`
`
`
`
`
`
`
`
`FIG. 5 (shownas a dashedline) and a tuned notchfilter
`
`
`
`
`
`
`
`of the typeillustrated in FIG. 1 (shownasa solid line).
`
`
`
`
`
`
`Thefilter illustrated in FIG. 5 has an overall Q of 45.467
`
`
`
`
`
`
`
`while the filter in FIG. 1a has an overall Q of 101.05. As
`
`
`
`
`
`
`
`
`can be readily appreciated, the notch filter of the inven-
`
`
`
`
`
`
`
`tion has a much sharper response and corresponding
`
`
`
`
`
`40% or greater improvementin bandwidth, characteris-
`
`
`
`
`
`
`
`
`tics which are highly desirable when used in higher
`
`
`
`
`
`
`frequency television channels. Thus, conventional fil-
`
`
`
`
`
`
`
`
`
`ters having Q’s ranging from 35-60 can be easily modi-
`
`
`
`
`
`
`
`fied by the practice of the invention to yield Q’s. of 70
`
`
`
`
`
`
`or greater with corresponding improvements in re-
`sponse.
`
`The invention has been described with reference to
`
`
`
`
`
`
`
`
`
`
`
`
`
`certain preferred embodimentsthereof. It will be under-
`
`
`
`
`
`
`
`stood, however, that variations and modifications are
`
`
`
`
`
`
`
`
`possibie within the scope of the appended claims. For
`
`
`
`
`
`
`
`example, although the invention was described with
`
`
`
`
`
`
`
`reference to a notchfilter having twofiltering sections,
`
`
`
`
`
`
`
`the invention is applicable to filters having more than
`
`
`
`
`
`
`
`twofiltering sections. For example, one or moreof the
`filter or. filter sections can be connected in series to
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`obtain better frequency response with moreattenuation.
`
`
`
`
`
`
`
`Theinventionis also applicableto filters in general and
`
`
`
`
`
`
`
`
`
`is not limited solely to notch filters. It will also be un-
`
`
`
`
`
`
`
`derstood that various permutations of the basic filter
`
`
`
`
`
`
`
`
`structure are possible, i.e., series capacitors and/or par-
`
`
`
`
`
`
`
`allel inductors can be used to replace single elements
`
`
`
`
`
`
`
`throughoutthefilter structure in any desired combina-
`
`
`
`
`
`
`
`tion. Several examples of such permutations are illus-
`trated in FIGS. 15-1e.
`
`
`
`Whatis claimedis:
`
`
`
`
`
`
`
`
`1. A filter comprising: an input terminal and an output
`
`
`
`
`
`
`
`terminal; a first network, including at least two series
`
`
`
`
`
`
`capacitors connected to at least two inductors and at
`
`
`
`
`
`
`
`least one capacitor arranged in parallel, coupled to the
`
`
`
`
`
`
`
`input terminal and electrical ground; a second network
`
`
`
`
`
`
`
`and a third network connected in parallel and coupled
`
`
`
`
`
`
`
`
`
`to the input terminal and the output terminal, wherein
`the second network includes at
`least two inductors
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`coupled in parallel and the third network includes at
`
`
`
`
`
`
`
`least one capacitor connected in series to at least two
`
`
`parallel inductors.
`
`
`
`
`
`
`
`
`2. The filter as claimed in claim 1, wherein the input
`
`
`
`
`
`
`
`terminal is coupled to a television signal source and the
`
`
`
`
`
`output terminal is coupled to a television monitor.
`
`
`
`
`
`
`
`3. The filter as claimed in claim 2, further comprising
`
`
`
`
`
`
`
`
`a capacitor connected between the output terminal and
`
`
`electrical ground.
`
`Ex. 1058, Page 13
`
`Ex. 1058, Page 13
`
`

`

`7
`
`
`
`5,148,133
`
`
`
`
`4. A filter comprising:
`
`
`
`
`
`
`
`an input terminal, an output terminal and an isolation
`
`
`
`
`
`
`
`
`section located between the input terminal and the
`
`
`output terminal;
`
`
`
`
`
`
`
`a first filtering section comprising a first network 5
`
`
`
`
`
`
`including at least two series capacitors connected
`
`
`
`
`
`
`
`
`to at least two inductors and at least one capacitor
`
`
`
`
`
`
`arranged in parallel, wherein the first network is
`
`
`
`
`
`
`
`connected to the input
`terminal and electrical
`
`
`
`
`
`
`ground, a second network and a third network 10
`
`
`
`
`
`
`
`connected in parallel and coupled to the input ter-
`
`
`
`
`
`
`
`
`minal and the isolation section, wherein the second
`
`
`
`
`
`
`network includesat least two inductors coupled in
`
`
`
`
`
`
`
`
`parallel and the third network includesat least one
`
`
`
`
`
`
`capacitor connected in series to at least two parallel
`
`
`inductors; and
`
`
`
`
`
`
`
`a second filter section comprising a fourth network
`
`
`
`
`
`
`
`and a fifth network connected in parallel and cou-
`
`
`
`
`
`
`
`
`pled to the isolation section and the output termi-
`
`
`
`
`
`
`
`nal, wherein the fourth network includes at least 20
`
`
`
`
`
`
`
`
`two inductors coupled in parallel and thefifth net-
`
`
`
`
`
`
`work includes at least one capacitor connected in
`
`
`
`
`
`
`
`series to at least two parallel inductors, and a sixth
`
`
`
`
`
`
`network including at least two series capacitors
`connectedto at least two inductors andat least one 25
`
`
`
`
`
`
`
`
`
`
`
`
`
`capacitor arranged in parallel, wherein the sixth
`
`
`
`
`
`
`
`networkis coupled to the output terminal and elec-
`
`
`trical ground.
`
`
`
`
`
`
`
`
`5. The filter as claimed in claim 4, wherein the input
`
`
`
`
`
`
`
`terminal is coupled to a television signal source and the 30
`
`
`
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`output terminal is coupled to a television monitor.
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`6. Thefilter as claimed in claim 4, wherein theisola-
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`tion section includes a capacitor which blocks AC/DC
`currents.
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`7. A filter comprising: an input terminal and an output 35
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`terminal, a first network coupled to the input terminal
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`15
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`8
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`and electrical ground including at least one capacitor
`connected in series to the combination of at least one
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`capacitor coupled in parallel with a plurality of induc-
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`tors, a second network coupled to the input terminal
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`and the output terminal including at least one inductor
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`connected in parallel to the combination ofat least one
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`capacitor coupled in series with a plurality of parallel
`inductors.
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`8. A filter as claimed in claim 7, further comprising a
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`third network and a fourth network coupled between
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`the second network and the output terminal, wherein
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`the third network is connected to an output of the sec-
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`ond network and to the output terminal and the fourth
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`networkis connected to output terminal and electrical
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`ground, and wherein the third network includesa single
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`inductor or a plurality of parallel inductors connected
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`in parallel with a single capacitor or.a plurality of series
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`capacitors in series with a single inductoror a plurality
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`of inductors, and the fourth network includes a single
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`capacitorora plurality of series capacitors connected to
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`a single capacitor or a plurality of series capacitors in
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`parallel with a single inductor or a plurality of parallel
`inductors.
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`9. The filter as claimed in claim 8, further comprising
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`a blocking capacitor coupled between the second net-
`work and the third network.
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`10. The filter as claimed in claim 7, further compris-
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`ing a capacitor coupled between the output of the sec-
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`ond network and electrical ground to improve higher
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`frequency response.
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`11. Thefilter as claimed in claim 8, further compris-
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`ing a capacitor coupled between an input to the third
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`network and electrical ground to improve higherfre-
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`quency response.
`*
`&
`&
`+.
`&
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`45
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`50
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`55
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`65
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`Ex. 1058, Page 14
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`Ex. 1058, Page 14
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