Surgery – Diagnostic testing – Cardiovascular
Reexamination Certificate
2000-09-08
2002-05-14
Evanisko, George R. (Department: 3762)
Surgery
Diagnostic testing
Cardiovascular
Reexamination Certificate
active
06389309
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a biological signal transmission apparatus of a medical telemeter for transmitting a biological signal from a transmitter through an antenna to a receiver and in particular to a biological signal transmission apparatus using a loop antenna, a microstrip antenna as an antenna.
2. Related Art
A system for transmitting by radio a biological signal detected on an electrode placed on a subject to a nearby computer diagnostic apparatus, etc., via an antenna for diagnosis is known. Hitherto, various propositions have been made as a transmission apparatus used with such a system.
In a proposition described in JP-A-60-97103U, two electrodes
502
and
503
attached to a chest belt
501
and a transmitter main unit
504
placed on a wrist of a subject are connected by electrode leads
505
and
506
, as shown in FIG.
34
. An antenna line
507
from the transmitter main unit
504
is placed closely on the leads
505
and
506
in parallel therewith and an end of the antenna line
507
is buried in the chest belt
501
. The electrode leads
505
and
506
and the antenna line
507
are insulated from each other and the end of the antenna line
507
is also electrically insulated so as not to touch the body surface of the subject.
According to the proposition, the antenna line
507
is placed closely on the leads
505
and
506
and thus can be made 1 m or longer without disturbing any motion, and the efficiency of the transmitter
504
can be improved and miniaturized for enhancing portability of the transmitter.
In a proposition described in JP-A-62-202804U, a pair of electrodes
201
and
202
is placed in unit cases
203
and
204
, which are opened at bottoms for exposing the electrodes
201
and
202
, and both ends of an antenna line
205
are connected to the electrodes
201
and
202
, as shown in FIG.
35
. The unit cases
203
and
204
are coupled by a connection cable
206
and the antenna line
205
is inserted into the connection cable
206
.
According to the proposition, the electrodes
201
and
202
placed in a pair of unit cases
203
and
204
are fitted to a heart rate detection part of a living body and a signal from the antenna line
205
is transmitted, so that the device is easily attached and detached and moreover can be placed without an oppressive feeling or a feeling of wrongness on the chest of the subject.
In a proposition described in JP-A-63-32501U, a device comprises a pair of electrodes
301
and
302
, a transmitter main unit
303
having electric circuitry for processing an electrocardiographic signal detected on the electrodes
301
and
302
, and an antenna
304
for sending the resultant signal to a receiver by a radio wave, as shown in FIG.
36
. The antenna
304
is covered with water-repellent fibers and is put on the surface of a human body.
According to the proposition, the antenna
304
is covered with water-repellent fibers and is connected to the transmitter main unit
303
so that it is put on the surface of a human body. Thus, when the device is attached to a subject, clothes of the subject do not swell locally and moreover it is not feared that the electrode
301
,
302
may be off the attachment point. Resultantly, sufficiently strong radio waves can be sent to the receiver in addition to ease of use.
In a proposition described in JP-A-9-108194, a base sheet
401
placed on the anterior chest wall of a subject is formed like an L letter, a longwise portion
401
a
is put along the breast bone line of the subject, and a widthwise portion
401
c
is directed toward the heart side from a corner
401
b
positioned near the xiphisternum of the subject, as shown in FIG.
37
. The base sheet
401
is formed on a rear with an adhesion layer made to adhere to the anterior chest wall. A first electrode
402
is attached in the proximity of the corner
401
b
, a second electrode
403
is attached in the proximity of the upper end part of the longwise portion
401
a
, and a third electrode
404
is attached in the proximity of a side end part of the widthwise portion
401
c
. Further, a fourth electrode
405
is attached slantingly below the second electrode
403
and a fifth electrode
406
is attached above the third electrode
404
.
Of the five electrodes arranged as described above, &agr; induction is detected between the electrodes
402
and
403
and &bgr; induction is detected between the electrodes
403
and
404
. &Dgr; induction for ischaemia of side and front and rear walls in a high-potential direction weak in sensitivity only with a induction and &bgr; induction is detected by means of the electrodes
405
and
406
. The electrocardiographic signals induced to the electrodes are amplified and modulated by a circuit unit
407
attached to the base sheet
401
and are transmitted to the receiver through an antenna
408
attached along the longwise portion
401
a.
According to the proposition, the electrodes
402
to
406
, the circuit unit
407
, and the antenna
408
are mounted integrally on the base sheet
401
, so that the device is easily placed on the subject and action is not limited.
In the examples in the related arts described above, the antennas are monopole antennas using the electricity length of a quarter the wave length. For example, assuming that the transmission frequency is 300 MHz, the wave length is 1 m and the antenna length becomes 25 cm. To place the monopole antenna so that it is not affected by a human body as much as possible, the monopole antenna may be placed in a direction perpendicular to the surface of a human body and distant from the human body. However, the antenna length is long (in this case, 25 cm), thus when the transmitter is placed on a human body, it disturbs the motion of the human body. If the transmitter is placed along the surface of the human body so as to facilitate the motion, radio waves radiated from the antenna are affected by the human body as described above, thus the gain is easily degraded. Also, although employing small and compact transmitter and electrode, there is still a problem that long using for standard limb lead (II) between electrodes disturb patient.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide a small-sized biological signal transmission apparatus that can emit a biological signal detected on an electrode placed on the surface of a living body to a receiver with stable and good sensitivity and can be easily placed on the living body.
According to an aspect of the present invention, there is provided a biological signal transmission apparatus comprising an electrode for detecting a biological signal, a support for supporting the electrode, the support being placed on a living body surface, a transmitter having electric circuitry for processing the biological signal detected on the electrode, and at least one loop antenna for emitting the biological signal processed by the electric circuitry to a receiver, the loop antenna being disposed so that an opening face is placed in a direction almost perpendicular to the living body surface.
According to another aspect of the present invention, there is provided a biological signal transmission apparatus comprising an electrode for detecting a biological signal, a support for supporting the electrode, the support being placed on a living body surface, a transmitter having electric circuitry for processing the biological signal detected on the electrode, and two loop antennas for emitting the biological signal processed by the electric circuitry to a receiver, the loop antennas being disposed so that opening faces are placed in a direction almost perpendicular to the living body surface and are almost at right angles to each other.
According to another aspect of the present invention, in the biological signal transmission apparatus, at least one of the loop antennas is contained in the transmitter.
According to another aspect of the present invention, in the biological signal transmission apparatus, at least one of the
Hosaka Hidehiro
Matsumura Fumiyuki
Sakata Hiroshi
Sekiguchi Tetsushi
Evanisko George R.
Nihon Kohden Corporation
LandOfFree
Biological signal transmission apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Biological signal transmission apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Biological signal transmission apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2820929