Multiplex communications – Quadruplex – Duplex diplex
Reexamination Certificate
1998-05-26
2002-04-02
Nguyen, Chau (Department: 2663)
Multiplex communications
Quadruplex
Duplex diplex
C455S078000, C333S103000
Reexamination Certificate
active
06366564
ABSTRACT:
This Application is a U.S. National Phase Application of PCT International Application PCT/JP976/03381.
FIELD OF THE INVENTION
The present invention relates to the field of diplexers, duplexers, and two-channel mobile communications equipment employed in mobile communications, particularly in mobile phones.
BACKGROUND OF THE INVENTION
Diplexers employed in mobile communications generally have the configuration shown in
FIGS. 9
to
11
. Specifically, a diplexer of the prior art has a circuit shown in
FIG. 9
which comprises a low-pass filter and high-pass filter formed in a low-dielectric ceramic material as shown in FIG.
10
.
In
FIG. 10
, a conductive layer
24
is formed on a low-dielectric layer
16
i
as a shield electrode, followed by a laminated low-dielectric layer
16
h
. Inductor electrodes
23
a
and
23
b
are formed on this low-dielectric layer
16
h
, followed by a laminated low-dielectric layer
16
g
. A capacitor electrode
22
is formed on this low-dielectric layer
16
g
, followed by a laminated low-dielectric layer
16
f
. A capacitor electrode
21
is formed on this low-dielectric layer
16
f
, followed by a laminated low-dielectric layer
16
e
. A conductive layer
20
is formed on this low-dielectric layer
16
e
as a shield electrode, followed by a laminated low-dielectric layer
16
d
. Capacitor electrodes
19
a
and
19
b
are formed on this low-dielectric layer
16
d
, followed by a laminated low-dielectric layer
16
c
. An inductor electrode
18
is formed on this low-dielectric layer
16
c
, followed by a laminated low-dielectric layer
16
b
. An inductor electrode
17
is formed on this low-dielectric layer
16
b
, followed by a laminated low-dielectric layer
16
a
. In the low-dielectric layer
16
b
, a via hole
25
is formed to create an electrical connection between the inductor electrodes
17
and
18
.
Next,
FIG. 11
shows a perspective of the diplexer of the prior art. The conductive layers
20
and
24
are connected with end electrodes
26
b
,
26
d
,
26
f
, and
26
g
at the side of the dielectric substance to form a shielded electrode by grounding the end electrodes
26
b
,
26
d
,
26
f
, and
26
g.
Also, as shown in
FIG. 9
, a first terminal
907
is formed by connecting an end electrode
26
a
and the inductor electrode
17
at the side of the dielectric substance, and a first inductor
902
is also formed by connecting the inductor electrodes
17
and
18
through the via hole
25
. The end electrode
26
a
is also connected to the capacitor electrode
19
a
at the side of the dielectric substance to form a first capacitor
901
between the conductive layer
20
. A common terminal
908
is formed by connecting the inductor electrode
18
and capacitor electrode
21
to an end electrode
26
c
at the side of the dielectric substance. The end electrode
26
c
is further connected to the capacitor electrode
19
b
at the side of the dielectric substance to form a second capacitor
903
between the conductive layer
20
. This is how a low-pass filter
910
is configured.
Next, a third capacitor
905
is formed with the capacitor electrode
22
facing the capacitor electrode
21
connected to the end electrode
26
c
. The end electrode
26
c
is also connected to the inductor electrode
23
b
at the side of the dielectric substance, and a second inductor
904
is formed by connecting the other end of the inductor electrode
23
b
to the end electrode
26
g
. In the same way, the capacitor electrode
22
is connected to the inductor electrode
23
a
at the side of the dielectric substance, and a third inductor
906
is formed by connecting the other end to the end electrode
26
f
. The capacitor electrode
23
is also connected to the end electrode
26
e
at the side of the dielectric substance to form a second terminal
909
. This is how a high-pass filter
911
is configured.
Attenuation of the low-pass filter
910
is increased in the passband frequency of the high-pass filter
911
, and attenuation of the high-pass filter
911
is increased in the passband frequency of the low-pass filter
910
to ensure mutual isolation.
However, since the number of mobile communications users has rapidly increased in recent years, the trend is towards enabling the use of a system employing two different frequency bands in one piece of communications equipment to make it more likely to secure a communications channel. In this case, a device for dividing two bands is required. If the diplexer of the prior art which comprises a low-pass filter and high-pass filter formed in a low-dielectric ceramic material is used for realizing such a system, due to structural limitations, the higher harmonics cannot be removed. In addition, the size will be larger due to design restrictions.
SUMMARY OF THE INVENTION
The present invention offers a small device for dividing two bands and also removing the higher harmonics.
The present invention has a configuration comprising a formed low-dielectric layer and high-dielectric layer. A low-pass filter and an inductor as a matching circuit for the low-pass filter are formed in the low-dielectric layer, and a band-pass filter and a capacitor as a matching circuit for the band-pass filter are formed in the high-dielectric layer.
This configuration allows the present invention to be embodied in a small device which can divide signals input to a common terminal into two bands and remove the higher harmonics.
REFERENCES:
patent: 5304967 (1994-04-01), Hayashi
patent: 5594394 (1997-01-01), Sasaki et al.
patent: 5634200 (1997-05-01), Kitakubo et al.
patent: 5945887 (1999-08-01), Makino et al.
patent: 6066993 (2000-05-01), Yamaoto et al.
patent: 6097268 (2000-08-01), Watanabe et al.
patent: 64-29131 (1989-01-01), None
patent: 4-301901 (1992-10-01), None
patent: 5-55811 (1993-03-01), None
patent: 8-204530 (1996-08-01), None
patent: 8-321738 (1996-12-01), None
Japanese language search report for Int'l Appln. No. PCT/JP97/03381 dated Jan. 20, 1998.
Hiraka Masahiro
Hurukawa Shigeo
Katsumura Hidenori
Kimura Suzushi
Kushitani Hiroshi
Lee Andy
Matsushita Electric - Industrial Co., Ltd.
Ratner & Prestia, PC
LandOfFree
Diplexer duplexer and two-channel mobile communications... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Diplexer duplexer and two-channel mobile communications..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Diplexer duplexer and two-channel mobile communications... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2820816