JPH0591007U - Duplexer - Google Patents

Abstract

(57) [Summary] [Structure] The first resonant electrodes 11, 12 and the second resonant electrodes 13, 14, 15, 16 are provided in a dielectric unit obtained by joining two dielectric substrates 20, 21. The phase absorption matching line 17 and the coupling electrodes 18 and 19 are provided. The ground electrode 10 is formed on substantially the entire outer surface of the dielectric substrates 20 and 21. [Effect] Inductive coupling between the resonance electrodes 12 and 13 is eliminated,
An integrated duplexer can be obtained in which the two sets of filter characteristics are not disturbed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a duplexer used as, for example, a duplexer in which a transmission filter and a reception filter are integrated.

[0002]

[Prior Art]

 A dielectric resonator in which an inner conductor is formed inside the dielectric block and an outer conductor is formed on the outer surface of the dielectric block, or multiple stripline resonance electrodes are formed on the surface of the dielectric substrate, and the opposite surface is grounded. A so-called triplate-type dielectric resonator in which two dielectric substrates each having electrodes formed on each other are stacked is used, for example, as a filter in the microwave band.

As described above, the integrated dielectric filter having a plurality of resonance electrodes provided in the dielectric body is coupled between the resonators as compared with, for example, a discrete type dielectric filter using a plurality of dielectric resonators. It does not require a coil, a capacitor, a board on which they are mounted, or a shield case that shields the entire system, etc., and has the features of a small number of parts and a simple assembly process.

Even when a duplexer in which two sets of filters are integrated, such as a duplexer in which a transmission filter and a reception filter are integrated, is configured, a plurality of resonant electrodes are provided in the dielectric and the outer surface of the dielectric is provided. It can be constructed by forming a ground electrode. An example thereof is shown in FIGS. 3 and 4.

FIG. 3 is an exploded perspective view of a conventional duplexer. In FIG. 3, reference numerals 20 and 21 are dielectric substrates. A plurality of grooves having a semicircular cross section are provided on the first main surface (upper surface in the drawing) of the dielectric substrate 20, and the resonance electrodes 11, 12, 13, 14, 15, 16 are formed on the inner surface of each groove. Further, the ground electrode 10 is formed on the second main surface (bottom surface in the figure) and four side surfaces of this dielectric substrate 20. On the other hand, on the first main surface (bottom surface in the figure) of the dielectric substrate 21, the same grooves and resonance electrodes as those in the case of the dielectric substrate 20 are formed. On the second main surface (upper surface in the figure) of the dielectric substrate 21, the signal input electrode 7 as a TX terminal for capacitively coupling to the resonance electrode 11, the ANT terminal 8, and the coupling electrode 23 for capacitively coupling to the resonance electrode 12. A phase absorption / matching line 22 for phase matching, a coupling electrode 24 for capacitively coupling to the resonance electrode 13, and a signal input / output electrode 9 as an RX terminal for capacitively coupling to the resonance electrode 16 are provided.

By joining the two dielectric substrates 20 and 21, a duplexer as shown in FIG. 4 is constructed. As a result, the two-stage resonator including the resonance electrodes 11 and 12 can be used as a transmission filter between the TX terminal 7 and the ANT terminal 8, and the four-stage resonator including the resonance electrodes 13, 14, 15, and 16 can be used as the ANT. It can be used as a reception filter between the terminal 8 and the RX terminal 9.

[0007]

[Problems to be solved by the device]

 In the duplexer according to the prior art shown in FIGS. 3 and 4, a phase absorption matching line for achieving phase matching between the transmission filter and the reception filter and a coupling for coupling to the resonance electrode at the final stage of the transmission filter. Since the electrode 23 and the coupling electrode 24 for coupling to the first-stage resonator of the receiving filter are formed on the outer surface of the dielectric substrate where the ground electrode is supposed to be formed, respectively, there is a seal between the transmitting filter and the receiving filter. There is no such thing as a filter, and the resonators of both filters are coupled, which may disturb the filter characteristics.

An object of the present invention is to provide a duplexer in an integrated type duplexer, in which phase matching between two filters is achieved and unnecessary coupling between the two filters is prevented to obtain stable filter characteristics. It is in.

[0009]

[Means for Solving the Problems]

 The duplexer of the present invention comprises a first plurality of resonance electrodes that pass a first frequency band, a second plurality of resonance electrodes that pass a second frequency band, and a part of the first resonance electrode. And a signal input / output common electrode for capacitive coupling, and a second coupling electrode for capacitively coupling a part of the second resonance electrode and the signal input / output shared electrode. And a phase absorption matching line arranged between the signal input / output common electrode and the ground in a dielectric unit formed by laminating two dielectric substrates, and at a part of the first resonance electrode. The first signal input / output electrode that is capacitively coupled, the second signal input / output electrode that is capacitively coupled to a part of the second resonant electrode, the lead-out electrode of the signal input / output common electrode, and the ground electrode are provided. It is provided on the outer surface of the dielectric unit.

[0010]

[Action]

 In the duplexer of the present invention, two dielectric substrates are laminated to form a dielectric unit. The dielectric unit includes a first plurality of resonance electrodes, a second plurality of resonance electrodes, and a first plurality of resonance electrodes. A coupling electrode, a second coupling electrode and a phase absorption matching line are provided respectively. The outer surface of the dielectric unit is provided with a first signal input / output electrode, a second signal input / output electrode, a lead-out electrode for a signal input / output common electrode, and an ground electrode. The first coupling electrode capacitively couples a part of the first resonance electrode and a signal input / output common electrode, and the second coupling electrode shares a signal input / output with a part of the second resonance electrode. Capacitive coupling between the electrodes. The phase absorption matching line is arranged between the signal input / output common electrode and the ground to match the phase at the signal input / output common electrode part.

As described above, since the first and second coupling electrodes and the phase absorption matching line are provided inside the dielectric unit and the outer surface of the dielectric unit is covered with the ground electrode, the first and second coupling electrodes are provided. There is no coupling between the resonators consisting of two resonance electrodes, and the filter characteristics are not disturbed.

[0012]

【Example】

 The structure of a duplexer which is an embodiment of the present invention is shown in FIGS.

FIG. 1 is an exploded perspective view, and in FIG. 1, reference numerals 20 and 21 are dielectric substrates. A total of six grooves having a semicircular cross section are provided on the first main surface (upper surface in the figure) of the dielectric substrate 20, and the resonance electrodes 11, 12, 13, 14, 15, 16 are formed on the inner surface thereof. is doing. A phase absorption matching line 17, a first coupling electrode 18 and a second coupling electrode 19 are further formed on the first main surface of the dielectric substrate 20.

Further, the ground electrode 10 is formed on substantially the entire second main surface (back surface in the figure) and four side surfaces of the dielectric substrate 20 except for a part thereof. Further, two signal input / output electrodes are formed from the side surface of the dielectric substrate 20 to the second main surface. Reference numeral 9 in the figure denotes one of the signal input / output electrodes. A total of six grooves having a semicircular cross section are formed on the first main surface (bottom surface in the figure) of the other dielectric substrate 21, and the electrode pattern formed on the first main surface of the dielectric substrate 20 is formed on the inner surface thereof. Form a plane-symmetrical electrode pattern. Further, the ground electrode 10 is formed on the entire second main surface and the four side surfaces of the dielectric substrate 21.

FIG. 2 is an external perspective view of a duplexer formed by joining the two dielectric substrates 20 and 21 shown in FIG. However, the top and bottom of the dielectric substrates 20 and 21 are reversed, and the open end side of the resonator is shown in front. In FIG. 2, reference numerals 1, 2, 3, 4, 5, and 6 are resonance electrode forming holes formed by joining two dielectric substrates.

Numeral 8 is a signal input / output common electrode continuous from the phase absorption matching line 17 shown in FIG. As shown in FIG. 2, the signal input / output electrodes 7 and 9 and the signal input / output common electrode 8 are formed so as to extend to a part of the second main surface (upper surface in the drawing) of the dielectric substrate 20. Here, the signal input / output electrode 7 is capacitively coupled with the vicinity of the open end of the resonance electrode 11 shown in FIG. 1, and the signal input / output electrode 9 is capacitively coupled with the vicinity of the open end of the resonance electrode 16 shown in FIG.

The signal input / output common electrode 8 is capacitively coupled with the vicinity of the open end of the resonance electrode 12 via the coupling electrode 18 shown in FIG. 1, and the open end of the resonance electrode 13 is coupled via the coupling electrode 19. Capacitively coupled with the surroundings.

An equivalent circuit of the duplexer shown in FIGS. 1 and 2 is shown in FIG. In FIG. 5, R1 and R2 are resonators based on the resonance electrodes 11 and 12 shown in FIG. 1, and R3, R4, R5 and R6 are resonators based on the resonance electrodes 13, 14, 15, and 16 shown in FIG. C 1 is a coupling capacitance formed between the resonance electrode 11 shown in FIG. 1 and the signal input / output electrode 7 shown in FIG. 2, and C 4 is formed between the resonance electrode 16 shown in FIG. 1 and the signal input / output electrode 9. Is the coupling capacity. Further, C2 is a coupling capacitance formed between the coupling electrode 18 and the resonance electrode 12 shown in FIG. 1, and C3 is a coupling capacitance formed between the coupling electrode 19 and the resonance electrode 13 shown in FIG. .. L is the inductance due to the phase absorption matching line 17 shown in FIG. The portion A in FIG. 5 functions as a matching circuit in the signal input / output common electrode portion. The resonators R1 and R2 are combline-coupled to act as a two-stage bandpass filter, and the resonators R3 to R6 are combline-coupled between adjacent resonators to act as a four-stage bandpass filter. .. Because of the above-described configuration, this duplexer is used as a duplexer having the signal input / output electrodes 7 and 9 shown in FIG. 2 as the TX terminal and the RX terminal, respectively, and the signal input / output shared electrode 8 as the ANT terminal. be able to.

As described above, the matching circuit (portion A in FIG. 5) in the signal input / output common electrode portion is provided inside the dielectric unit, and the outer surface of the dielectric unit is substantially entirely except the signal input / output electrode portion. Since the ground electrode is formed in the resonator, the coupling between the adjacent resonators (resonance electrodes 12-13 in FIG. 1) of the two groups of resonators is also eliminated, and the filter characteristics are not disturbed.

In the above embodiment, the combline filter is taken as an example, but an interdigital filter can be similarly applied.

[0021]

[Effect of the device]

 According to this invention, the circuit for performing phase matching between the two filters in the signal input / output common electrode part is integrally provided in the dielectric unit and the ground electrode is formed on the outer surface, so that the coupling between the two filters is eliminated and the filter characteristics are improved. You can get a good duplexer.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a duplexer according to an embodiment of the present invention.

FIG. 2 is an external perspective view of the duplexer according to the first embodiment.

FIG. 3 is an exploded perspective view showing a structure of a duplexer according to a conventional technique.

FIG. 4 is an external perspective view of a conventional duplexer.

FIG. 5 is an equivalent circuit diagram of the duplexer according to the embodiment.

[Explanation of symbols]

 1 to 6-Resonant electrode forming hole 7-Signal input / output electrode as TX terminal 8-Signal input / output electrode as ANT terminal 9-Signal input / output electrode as RX terminal 10-Ground electrode 11-16-Resonance electrode 17 -Phase absorption matching line 18,19-Coupling electrode 20,21-Dielectric substrate

Claims (1)

[Scope of utility model registration request] 1. A first plurality of resonance electrodes that pass a first frequency band, a second plurality of resonance electrodes that pass a second frequency band, a part of the first resonance electrode, and a signal. A first coupling electrode for capacitively coupling the input / output common electrode;
A second coupling electrode for capacitively coupling a part of the second resonance electrode and the signal input / output common electrode, and a phase absorption matching line arranged between the signal input / output common electrode and ground. A first signal input / output electrode capacitively coupled to a part of the first resonance electrode and a part of the second resonance electrode, the first signal input / output electrode being provided in a dielectric unit formed by stacking two dielectric substrates. A duplexer in which a second signal input / output electrode capacitively coupled to, a lead-out electrode of the signal input / output common electrode, and a ground electrode are provided on the outer surface of the dielectric unit.