An isolating circuit and dielectric filter for use therein

Claim 2

An isolating circuit for isolating a first frequency signal in a first frequency range and a second frequency signal in a second frequency range which is higher than the first frequency range, the isolating circuit comprising: an antenna terminal; a first filter having a first input terminal and a first output terminal, for being coupled to first input signal including the first frequency signal at said first input terminal and for attenuating first frequency compornents of the first input signal below the first frequency range at a first attenuation rate and second frequency compornents of the first input signal above the first frequency range at a second attenuation rate, one of said input and output terminals being coupled to said antenna terminal, said first filter further having first setting means for setting the first attenuation rate and second attenuation rate so that the second attenuation rate is greater than the first attenuation rate; and a second filter having a second input terminal and a second output terminal, for being coupled to second input signal including the second frequency signal at said second input terminal and for attenuating third frequency compornents of the second input signal below the second frequency range at a third attenuation rate and fourth frequency compornents of the second input signal above the second frequency range at a fourth attenuation rate, one of said input and output terminals being coupled to said antenna terminal, said second filter further having second setting means for setting the third attenuation rate and fourth attenuation rate so that the third attenuation rate is greater than the fourth attenuation rate.

Claim 3

The circuit according to claim 1, wherein said first filter includes first, second and fourth resonators, said first resonator being coupled to said first input terminal, said fourth resonator being coupled to said first output terminal, said second resonator being inductively coupled to both of said first and fourth resonators; wherein said first setting means capacitively couple said second resonator to one of said first and fourth resonators; wherein said second filter includes fifth, sixth and eighth resonators, said fifth resonator being coupled to said second input terminal, said eighth resonator being coupled to said second output terminal, said sixth resonator being capacitively coupled to both of said fifth and eighth resonators; and wherein said second setting means capacitively couple said sixth resonator to oone of said fifth and eighth resonators.

Claim 4

The circuit according to claim 2, each of said first, second, fourth, fifth, sixth and eighth resonator includes; a dielectric block, said dielectric block having a top surface, a bottom surface and a side surface extending from said top surface to said bottom, said dielectric block further having an interior surface defining a hole extending from the top surface to the bottom surface, a side conductive layer covering said side surface, a bottom conductive layer covering the bottom surface and electrically connected to said side conductive layer, and an inner conductive layer covering said interior surface, said inner conductive layer being electrically connected to said bottom conductive layer and spaced from said side layer at said top surface; wherein said first setting means having a first conductive part having first and second edge portions thereof, said first edge portion being coupled to said second resonator, said second edge portion being coupled to one of said first and fourth resonators; and wherein said second setting means have a second conductive part having third and fourth edge portions thereof, said third edge portions being coupled to said sixth resonator, said fourth edge portion being coupled to one of said fifth and eighth resonators.

Claim 5

The circuit according to claim 3, wherein said first setting means has first and second insulating bushings each having a recess therein, said first insulating bushing being disposed in said dielectric block of said second resonator so as to be surround by said inner conductive layer of said second resonator, said second insulation bushing being disposed in said dielectric block of one of said first and fourth resonators so as to be surrounded by said inner conductive layer of the one of said first and fourth resonators, said first edge portion being inserted into said recess of said first insulating bushing, said second edge portion being inserted into said recess of said second bushing; and wherein said second setting means has third and fourth insulating bushings each having a recess therein, said third insulating bushing being disposed in said dielectric block of said sixth resonator so as to be surround by said inner conductive layer of said sixth resonator, said third insulating bushing being disposed in said dielectric block of one of said fifth and eighth resonators so as to be surrounded by said inner conductive layer of the one of said fifth and eight resonators, said third edge portion being inserted into said recess of said third insulating bushing, said fourth edge portion being inserted into said recess of said fourth bushing.

Claim 6

The circuit according to claim 2, wherein said first filter further includes a third resonator, said third resonator inductively coupling said second resonator to said fourth resonator; wherein said first setting means has first and second capacitance circuits, said first capacitance circuit capacitively coupling said first resonator to said second resonator, said second capacitance circuit capacitively coupling said third resonator to said fourth resonator; wherein said second filter further includes a seventh resonator, said seventh resonator capacitively coupling said sixth resonator to said eighth resonator; and wherein said second setting means has third and fourth capacitance circuits, said third capacitance circuit capacitively coupling said fifth resonator to said sixth resonator, said fourth capacitance circuit capacitively coupling said seventh resonator to said eighth resonator.

Claim 7

The circuit according to claim 5, each of said first, second, third and fourth capacitance circuits has a capacitor and a inductor, said capacitor being connecting with said inductor in series.

Claim 8

The circuit according to claim 1, wherein said first filter includes first, second, third and fourth resonators, said first resonator being coupled to said first input terminal, said fourth resonator being coupled to said first output terminal, said second resonator being inductively coupled to said first resonator, said third resonator being inductively coupled to said fourth resonator; wherein said first setting means has first and second capacitance circuits, said first capacitance circuit capacitively coupling said first resonator to said second resonators, said second capacitance circuit capacitively coupling said third resonator to said fourth resonator; wherein said second filter includes fifth, sixth, seventh and eighth resonators, said fifth resonator being coupled to said second input terminals, said eighth resonator being coupled to said second output terminal, said sixth resonator being capacitively coupled to said fifth resonator, said seventh resonator being capacitively coupled to said eighth resonator; and wherein said second setting means has third and fourth capacitor circuits, said third capacitance circuit capacitively coupling said fifth resonator to said sixth resonators, said fourth capacitance circuit capacitively coupling said seventh resonator to said eighth resonator.

Claim 9

The circuit according to claim 7, each of said first, second, third, fourth, fifth, sixth, seventh and eighth resonator includes; a dielectric block, said dielectric block having a top surface, bottom surface and a side surface extending from said top surface to said bottom, said dielectric block further having an interior surface defining a hole extending from the top surface to the bottom surface, a side conductive layer covering said side surface, a bottom conductive layer covering the bottom surface and electrically connected to said side conductive layer, and an inner conductive layer covering said interior surface, said inner conductive layer being electrically connected to said bottom conductive layer and spaced from said side layer at said top surface; wherein said first capacitance circuit has a first conductive part having first and second edge portions thereof, said first edge portion being coupled to said first resonator, said second edge portion being coupled to said second resonator; wherein said second capacitance circuit has a second conductive part having third and fourth edge portions thereof, said third edge portion being coupled to said third resonator, said fourth edge portion being coupled to said fourth resonator; wherein said third capacitance circuit has a third conductive part having fifth and sixth edge portions thereof, said fifth edge portion being coupled to said fifth resonator, said sixth edge portion being coupled to said sixth resonator; and wherein said fourth capacitance circuit has a fourth conductive part having seventh and eighth edge portions thereof, said seventh edge portion being coupled to said seventh resonator, said eighth edge portion being coupled to said eighth resonator.

Claim 10

The circuit according to claim 8, wherein said first capacitance circuit further has first and second insulating bushings each having recess therein, said first insulating bushing being disposed in said dielectric block of said first resonator so as to be surround by said inner conductive layer of said first resonator, said second insulating bushing being disposed in said dielectric block of said second resonator so as to be surrounded by said inner conductive layer of said second resonators, said first edge portion being inserted into said recess of said first insulating bushing, said second edge portion being inserted into said recess of said second bushing; wherein said second capacitance circuit has third and fourth insulating bushings each having a recess therein, said third insulating bushing being disposed in said dielectric block of said third resonator so as to be surround by said inner conductive layer of said third resonator, said fourth insulating bushing being disposed in said dielectric block of said fourth resonator so as to be surrounded by said inner conductive layer of said fourth resonators, said third edge portion being inserted into said recess of said third insulating bushing, said fourth edge portion being inserted into said recess of said fourth bushing; wherein said third capacitance circuit has fifth and sixth insulating bushings each having a recess therein, said fifth insulating bushing being disposed in said dielectric block of said fifth resonator so as to be surround by said inner conductive layer of said fifth resonator, said sixth insulating bushing being disposed in said dielectric block of said sixth resonator so as to be surrounded by said inner conductive layer of said sixth resonators, said fifth edge portion being inserted into said recess of said fifth insulating bushing, said sixth edge portion being inserted into said recess of said sixth bushing; wherein said fourth capacitance circuit has seventh and eighth insulating bushings each having a recess therein, said seventh insulating bushing being disposed in said dielectric block of said seventh resonator so as to be surround by said inner conductive layer of said seventh resonator, said eighth insulating bushing being disposed in said dielectric block of said eighth resonator so as to be surrounded by said inner conductive layer of said eighth resonators, said seventh edge portion being inserted into said recess of said seventh insulating bushing, said eighth edge portion being inserted into said recess of said eighth bushing.

Claim 11

The circuit according to claim 7, each of said first, second third and fourth capacitance circuits has capacitor and a inductor, said capacitor being connecting with said inductor in series.

Claim 12

The dielectric filter comprising: a dielectric block having a top surface, a bottom surface and a side surface, said dielectric block further having a plurality of interior surfaces defining respective holes, said holes each extending from said top surface to said bottom surface; a side conductive layer covering said side surfaces; a bottom conductive layer covering said bottom surface and being electrically connected to the side layer; first, second, third and fourth inner conductive layers covering said interior surfaces, each of said first, second third and fourth inner layer being electrically connected to said bottom layer, said second inner layer being provided between the first and third inner layers, said third inner layer being provided between the second and fourth inner layers; and a first coupling means for inductively and capacitively coupling said first inner layer to said second inner layer.

Claim 13

The dielectric filter comprising: a dielectric block having a top surface, a bottom surface and a side surface, said dielectric block further having a plurality of interior surfaces defining respective holes, said holes each extending from said top surface to said bottom surface; a side conductive layer covering said side surfaces; a bottom conductive layer covering said bottom surface and being electrically connected to the side layer; first, second, third and fourth inner conductive layers covering said interior surfaces, each of said first, second third and fourth inner layer being electrically connected to said bottom layer, said second inner layer being provided between the first and third inner layers, said third inner layer being provided between the second and fourth inner layers; and a first coupling means for inductively and capacitively coupling said first inner layer to said second inner layer.

Claim 14

The dielectric filter according to claim 11, wherein said dielectric filter includes a second coupling means for inductively and capacitively coupling said third inner layer to said fourth inner layer.

Claim 15

The dielectric filter according to claim 12, wherein each of said first and second coupling means includes first and second insulating bushings having a recess therein and a conductive part having first and second edge portions, said first and second edge portions being respectively inserted into said recesses of said first and second insulating bushings, said first and second bushings of said first coupling means being respectively fitted into said holes covered with said first and second inner layers, said first and second bushings of said second coupling means being respectively fitted into said holes covered with said third and second inner layers.

Claim 16

The dielectric filter according to claim 11, wherein said dielectric filter further has first, second and third coupling layers each covering said top surface, said first coupling layer being spaced from and provided between said first and second inner layers, said second coupling layer being spaced from and provided between said second and third inner layers, said coupling layer being spaced from and provided between said third and fourth inner layers.

Claim 17

The dielectric filter according to claim 14, wherein each of said first, second and third inner layers is electrically connected to said side layer so as to inductively couple first, second, third and fourth inner layers one after another.

Claim 18

The dielectric filter according to claim 15, wherein said dielectric filter includes a second coupling means for inductively and capacitively coupling said third inner layer to said fourth inner layer.

Claim 19

The dielectric filter according to claim 16, wherein each of said first and second coupling means includes first and second insulating bushings having a recess therein and a conductive part having first and second edge portions, said first and second edge portions being respectively inserted into said recesses of said first and second insulating bushings, said first and second bushings of said first coupling means being respectively fitted into said holes covered with said first and second inner layers, said first and second bushings of said second coupling means being respectively fitted into said holes covered with said third and second inner layers.

Claim 20

The dielectric filter according to claim 14, wherein each of said first, second and third inner layers is spaced from said side layer so as to capacitively couple first, second, third and fourth inner layers one another.

Claim 21

The dielectric filter according to claim 18, wherein said dielectric filter includes a second coupling means for inductively and capacitively coupling said third inner layer to said fourth inner layer.

Claim 22

The dielectric filter according to claim 19, wherein each of said first and second coupling mean includes first and second insulating bushings having a recess therein and a conductive part having first and second edge portions, said first and second edge portions being respectively inserted into said recesses of said first and second insulating bushings, said first and second bushings of said first coupling means being respectively fitted into said holes covered with said first and second inner layers, said first and second bushings of said second coupling means being respectively fitted into said holes covered with said third and second inner layers.