JP2023013503A - Biological information monitor - Google Patents

Abstract

To provide a biological information monitor capable of measuring an electric wave state without requiring any spectrum analyzer as an external measuring instrument and regardless of any situation of monitoring of biological information.SOLUTION: A central monitor includes: a demodulation unit having a plurality of demodulation circuits for individually demodulating a plurality of pieces of biological information transmitted from a plurality of biological information acquisition terminals by radio; and an electric field intensity measurement unit that is provided apart from the demodulation unit and measures electric field intensity of a medical telemeter band including at least all of target frequency bands of demodulation of the demodulation unit.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD The present invention relates to a biological information monitor that receives biological information transmitted wirelessly, such as a central monitor.

2. Description of the Related Art Conventionally, a central monitor installed at a nurse station in a medical institution is known as a biological information monitor for monitoring the conditions of a plurality of patients. The central monitor receives each patient's biological information (e.g., electrocardiogram, blood pressure, arterial blood oxygen saturation, etc.) from the bedside monitor installed at the bedside of each patient in the intensive care unit or hospital room, and displays it on the screen. (see, for example, Patent Document 1). The central monitor can also receive and display biological information wirelessly transmitted from a telemeter transmitter or the like attached to the patient.

In order for the central monitor to collect and display the biological information transmitted wirelessly, the central monitor must be able to correctly demodulate the biological information transmitted wirelessly.

By the way, in general, wireless communication between bedside monitors and telemeter transmitters (hereinafter referred to as "biological information acquisition terminals") in hospitals and the central monitor is performed via the antenna installed in the central monitor or in the corridor. The central monitor may not be able to demodulate the biometric information correctly depending on the location of the biometric information acquisition terminal and the radio propagation environment. For example, if the biological information acquisition terminal is located far from the antenna, or if there is an obstacle that blocks radio waves between the antenna and the biological information acquisition terminal, or if interference due to noise occurs, There is a possibility that the central monitor will not be able to demodulate biometric information.

Conventionally, some central monitors have, as one of their maintenance functions, the function of measuring the strength of the received electric field from the biological information acquisition terminal and displaying the measurement results. Then, for example, when the received electric field strength from the biological information acquisition terminal is lower than a predetermined threshold value, it is displayed on the central monitor.

As a result, the user of the central monitor is aware that the biometric information acquisition terminal is not placed in an appropriate position so that biometric information can be transmitted to the central monitor, that is, the biometric information acquisition terminal is placed in a poor wireless environment. I can recognize that. By using such a maintenance function, it is possible to prompt the user to place the biometric information acquisition terminal in an appropriate wireless environment.

JP-A-2005-124903

By the way, the central monitor has a plurality of reception modules so that it can receive biometric information from a plurality of biometric information acquisition terminals at the same time. In order to install the central monitor in an appropriate location and assign the biometric information acquisition terminal to an appropriate channel, the frequency band of radio waves used by this medical telemeter (hereinafter referred to as "medical telemetry frequency band") It is necessary to know the radio wave condition of For example, when installing a central monitor on a certain floor, it is necessary to know the influence of floor noise on the medical telemetry frequency band.

Therefore, many central monitors have, as a maintenance function, the function of a spectrum analyzer for measuring radio wave characteristics in the medical telemeter frequency band. The function of this spectrum analyzer is, for example, using an idle receiving module that does not receive biological information among a plurality of receiving modules for demodulating biological information from a plurality of biological information acquisition terminals with different transmission frequencies. is done.

However, as a matter of course, the receiving module used for the spectrum analyzer function does not demodulate biological information (hereinafter this is sometimes referred to as monitoring biological information) during the period of processing. Inconvenience arises that it cannot be used. Conversely, there is a problem that the radio wave state cannot be measured during the period when all receiving modules are used for monitoring biological information.

Aside from the central monitor, it is conceivable to provide a spectrum analyzer as an external measuring instrument to measure the state of radio waves, but doing so would result in a more complicated system configuration. A spectrum analyzer as an external instrument is generally expensive and requires a high degree of expertise to operate. It is not realistic for a user to purchase a spectrum analyzer as an external measuring instrument and learn how to operate it just to measure the radio wave state in the frequency band of a medical telemeter.

The present invention has been made in consideration of the above points, does not require a spectrum analyzer as an external measuring instrument, and measures radio wave conditions in the frequency band of a medical telemeter regardless of the status of biological information monitoring. To provide a vital information monitor capable of

One aspect of the biological information monitor of the present invention is
a demodulation unit having a plurality of demodulation circuits that respectively demodulate a plurality of biological information wirelessly transmitted from a plurality of biological information acquisition terminals;
an electric field intensity measurement unit provided separately from the demodulation unit for measuring electric field intensity in a medical telemetry band including at least all frequency bands demodulated by the demodulation unit;
Prepare.

According to the present invention, it is possible to measure the radio wave state in the frequency band of a medical telemeter without requiring a spectrum analyzer as an external measuring device and regardless of the state of biological information monitoring.

1 is a diagram showing a schematic configuration of a biological information monitoring system to which a central monitor of an embodiment is applied; FIG. Block diagram showing the main configuration of the central monitor Block diagram showing the configuration of the receiver Diagram showing an example of biological information displayed on the central monitor Diagram showing an example of the electric field strength display screen on the central monitor

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a biological information monitoring system to which a central monitor of this embodiment is applied. A biological information monitoring system 10 in FIG. 1 is installed, for example, in a hospital.

A central monitor 100 is provided at the nurse station, and the central monitor 100 receives information from biological information acquisition terminals such as bedside monitors 20 (20-1 to 20-n) or telemeter transmitters 30-1 to 30-m. Radio-transmitted biological information of each patient is received via antennas AN1, AN2-1, AN2-2, and AN2-3.

The antennas AN1, AN2-1, AN2-2, AN2-3 are directly attached to the central monitor 100 or connected to the central monitor 100 by cables. Specifically, the antenna AN1 is directly attached to the central monitor 100, and the antennas AN2 (AN2-1 to AN2-3) are connected to the central monitor 100 via cables 400. FIG. Antenna AN2 is installed, for example, in the ceiling of the corridor of the hospital.

As for the configuration of the antenna AN2, a so-called antenna system may be employed, or a leaky coaxial cable system may be employed. The antenna system uses a whip antenna or the like as an antenna, and the antennas AN2-1 to AN2-3 are connected by wire. The leaky coaxial cable system uses leaky coaxial cables as antennas AN2-1 to AN2-3. The antennas AN1 and AN2 may be of any type as long as they comply with the specified low-power radio standard. Also, the number of antennas is not limited to the example in FIG.

In practice, the biological information wirelessly transmitted from the bedside monitor 20 and the telemeter transmitter 30 (that is, the biological information acquisition terminal) is first received by the antenna AN1 or AN2. In the example of FIG. 1, the biological information transmitted from the telemeter transmitter 30-m is received by the antenna AN1, the bedside monitors 20-1 and 20-n, and the biological information transmitted from the telemeter transmitter 30-1. Information is received at the wired antenna AN2.

In this manner, biological information wirelessly transmitted from medical terminals such as the bedside monitor 20 and the telemeter transmitter 30 is received and collected by the central monitor 100 and displayed on the central monitor 100 .

FIG. 2 is a block diagram showing the main configuration of the central monitor 100 according to this embodiment.

The central monitor 100 inputs the signals received by the antennas AN1 and AN2 to the receiving section 200 . The receiving unit 200 demodulates the modulated biological information by performing predetermined radio processing on the input signal. The receiving unit 200 also has a function of measuring the electric field intensity of radio waves in the medical telemetry frequency band (420 MHz to 450 MHz). A detailed configuration of the receiving unit 200 will be described later.

Here, the medical telemeter frequency band will be briefly explained. According to the "Operating Regulations for Low Power Medical Telemeters" determined by the Japan Electronics and Information Technology Industries Association (JEITA), 420 to 450 MHz is defined as the operating frequency band for medical telemeters. Furthermore, six frequency bands (which may be called bands) 1 to 6 are assigned in the range of 420 to 450 MHz. Each frequency band 1-6 can be assigned 40, 80 or 120 channels (which may also be referred to as "floors" or "biometric terminals"). Incidentally, the interval of each channel is 12.5 kHz.

The biological information demodulated by the receiving section 101 is input to the biological information analyzing section 110 . The biological information analysis unit 110 forms a biological information waveform from the biological information and calculates the maximum value, the minimum value, the average value, and the like.

The output of the biological information analysis section 110 is input to the display control section 120 and the alarm control section 130 . The display control section 120 switches the display based on an operation signal from the operation section 180 . The display control unit 120 displays biological information such as an electrocardiogram, SpO2 and blood pressure on the display unit 140 . In addition, display control section 120 displays an alarm on display section 140 when an alarm output instruction signal is input from alarm control section 130 . An alarm output instruction signal from the alarm control unit 130 is also input to an alarm indicator 150 including an LED (Light Emitting Diode), a speaker, etc., and an alarm is output by light or sound.

On the other hand, information on the electric field intensity of the radio waves measured by the receiving unit 200 is output to the display control unit 120 . The electric field intensity information here is, for example, information representing the electric field intensity in a two-dimensional graph in which the horizontal axis is frequency and the vertical axis is power (or voltage). This two-dimensional graph is displayed on the display unit 140 by the display control unit 120 .

The central monitor 100 also has a control section 170 , an operation section 180 and a barcode reader 190 . Based on the biometric information acquisition terminal identification information input from the operation unit 180 or the barcode reader 190, the control unit 170 assigns and associates the carrier frequency with each biometric information acquisition terminal, and transmits the frequency assignment information to the reception unit 200. output to

FIG. 3 is a block diagram showing the configuration of the receiving section 200. As shown in FIG.

The receiver 200 inputs the signals received by the antennas AN1 and AN2 to the distributor 230 through the bandpass filter (BPF) 210 and the amplifier (AMP) 220 .

Distributor 230 outputs the input received signal to demodulation section 240 and electric field strength measurement section 250 . Here, for example, the distributor 230 may select either one of the signals of the antenna AN1 or the antenna AN2 and output it to the demodulation unit 240 and the electric field strength measurement unit 250, and combine the signals of the antenna AN1 and the antenna AN2. The resulting signal may be output to the demodulation section 240 and the electric field strength measurement section 250 .

The distribution of the distributor 230 is controlled, for example, by the user's operation of the operation unit 180 . Thereby, for example, when the user wants to know the electric field intensity based on the signal received by the antenna AN1, the distributor 230 outputs the signal received by the antenna AN1 to the electric field intensity measuring section 250. FIG.

Further, the distributor 230 may select which received signal of the antennas A1 and AN2 to distribute to each of the demodulation circuits 1 to 12 included in the demodulator 240. FIG. For example, if the telemeter transmitter 30-1 in FIG. 1 is assigned to the demodulation circuit 1, the signal from the telemeter transmitter 30-1 should be larger at the antenna AN2 than at the antenna AN1. The device 230 preferably distributes the received signal of the antenna AN2 to the demodulation circuit 1.

The demodulation unit 240 has demodulation circuits (which may be called “receiving modules”) for the number of floors (which may be called “the number of channels” or “the number of biometric information acquiring terminals”). The example of FIG. 3 has demodulation circuits 1 to 12 for 12 floors. Specifically, each of the demodulation circuits 1 to 12 demodulates biological information by multiplying each input signal by a different carrier frequency. For example, demodulation circuit 1 multiplies carrier frequency 1, demodulation circuit 2 multiplies carrier frequency 2, .

The biometric information of each floor (each biometric information acquisition terminal) demodulated by the demodulation unit 240 is converted by the conversion circuit 270 into data suitable for analysis by the biometric information analysis unit 110 (FIG. 2).

In addition to this configuration, the receiving section 200 of the central monitor 100 of the present embodiment has an electric field strength measuring section 250 in addition to the demodulating section 240 that demodulates the biological information. The electric field intensity measurement unit 250 measures the electric field intensity of the medical telemetry band including at least all demodulation frequency bands demodulated by the demodulation unit 240 .

The electric field intensity measurement unit 250 of this embodiment measures the electric field intensity in the medical telemeter band by a sweep method. Since the electric field strength measurement using the sweep method is a known technique, it will be briefly described here. The electric field strength measuring section 250 converts the input signal into an IF (intermediate frequency) using a mixer and a local oscillator. At this time, the frequency of the local oscillator is automatically swept and converted to IF, and the power value passed through the narrow-band IF filter is output as electric field intensity information. Note that the electric field intensity measurement unit 250 may measure the electric field intensity information by the FFT method instead of the sweep method.

By measuring and displaying the field strength of radio waves in the medical telemeter band by the field strength measuring unit 250, the user can grasp the radio wave environment of the channel to which the biological information acquisition terminal is assigned.

The operations of distributor 230 , demodulator 240 and electric field strength measuring section 250 are controlled by radio control section 260 . For example, based on the frequency allocation information from the control unit 170, the radio control unit 260 controls which demodulation circuit among the demodulation circuits 1 to 12 is operated. For example, the carrier frequency 1 is assigned to the bedside monitor 20-1, the carrier frequency 2 is assigned to the bedside monitor 20-n, the carrier frequency 7 is assigned to the telemeter transmitter 30-1, and the telemeter transmitter 30 When carrier frequency 9 is assigned to -m, demodulation circuits 1, 2, 7 and 9 are operated.

In addition, the radio control unit 260 sets the carrier frequencies 1 to 12 of the demodulation circuits 1 to 12 so that the demodulation circuits 1 to 12 can be called "channels" or "biological information acquisition terminals." ).

FIG. 4 is a diagram showing a display example of biological information displayed on the display unit 140 of the central monitor 100. As shown in FIG. In the example of FIG. 4, the biometric information for eight floors is displayed, but according to the configuration of FIG. .

FIG. 5 is a diagram showing an example of a received electric field intensity display image displayed on the display unit 140 of the central monitor 100. As shown in FIG.

In the example of FIG. 5, a field strength measurement selection area AR1, a field strength graph area AR2, a band selection area AR3, an antenna selection area AR4, and a scan start position adjustment area AR5 are displayed. In the case of the present embodiment, the display unit 140 has a touch panel configuration, an operation signal corresponding to the user's touch operation is input to the control unit 170, and various controls are changed according to the operation signal. It's like

A "spectral analyzer only" button is displayed in the reception strength measurement selection area AR1. When the "special spectrum analyzer" button is touch-operated, the electric field strength measurement unit 250 performs electric field strength measurement. In addition, RF-01 to RF-12 buttons are displayed in the reception strength measurement selection area AR1. These buttons correspond to the demodulation circuits 1 to 12. For example, when the RF-01 button is touch-operated, the demodulation circuit 1 measures the electric field intensity, and for example, the RF-02 button is touch-operated. Then, the demodulation circuit 2 measures the electric field intensity.

In other words, the demodulation circuits 1 to 12 have the function of measuring the electric field strength in the medical telemeter band in addition to the function of demodulating the biological information, like the electric field strength measuring section 250 . In other words, in order to demodulate biological information, a configuration similar to that of the electric field strength measurement section 250 such as a mixer and a local oscillator is required. there is However, since the demodulation of the biological information of the present embodiment is not performed, and the electric field strength measurement unit 250 dedicated to electric field strength measurement is provided, the radio wave state of the frequency band of the medical telemeter is measured regardless of the monitoring state of the biological information. can do.

The electric field intensity graph area AR2 displays the electric field intensity of each channel. In the example shown in the figure, the electric field strength of the band in the 2000s out of the 6 bands (1000s, 2000s, 3000s, 4000s, 5000s, and 6000s) that make up the medical telemetry band is displayed. . By selecting a desired band in the band selection area AR3, the user can determine which band's electric field strength is to be measured and displayed. In the example shown in the figure, each band displays the electric field intensity for 120 channels.

The user can select an antenna for measuring the electric field intensity by performing a touch operation on the antenna selection area AR4. For example, when the "antenna 1" button is touched, the electric field strength of the signal received by the antenna AN1 is measured and displayed, and when the "antenna 2" button is touched, the electric field strength of the signal received by the antenna AN2 is measured and displayed. Incidentally, it is not limited to the case of selecting any one antenna, and all two or more antennas may be selected to measure and display the electric field intensity of their composite received signals.

The user can adjust the scan start position for measuring and displaying the electric field intensity by performing a touch operation on the scan start position adjustment area AR5. Here, it takes several tens of seconds, for example, to scan the electric field strength of all channels in the band, depending on the performance of the equipment. Therefore, when scanning is simply started from the channel with the lowest frequency and the channel of interest is a channel with a high frequency, the user has to wait a long time to know the electric field strength around the channel of interest. There must be.

The user can avoid such inconvenience by performing a touch operation on the scan start position adjustment area AR5. For example, if the target channel is the 2115th channel, the user touches the "110" button in the scan start position adjustment area AR5. As a result, the electric field intensity is measured and displayed in order from channel "2110", so that the user can know the electric field intensity around channel 2115, which is the target channel, in a short period of time.

As described above, according to the present embodiment, the central monitor 100 receives a plurality of pieces of biological information wirelessly transmitted from a plurality of biological information acquisition terminals (bedside monitor 20, telemeter transmitter 30), respectively. A demodulation unit 240 having a plurality of demodulation circuits (demodulation circuits 1 to 12) for demodulation, and a demodulation unit 240 provided separately from the demodulation unit 240. Measures the electric field strength of the medical telemeter band including at least the entire frequency band demodulated by the demodulation unit 240. and an electric field intensity measurement unit 250 that performs the measurement.

As a result, the radio wave condition can be measured by the electric field strength measuring unit 250 regardless of the usage status of the demodulation circuits 1 to 12 of the demodulation unit 240, so the spectrum analyzer is not required as an external measuring device, and the biological information monitoring status It is possible to realize the central monitor 100 that can measure the radio wave state regardless.

Specifically, the electric field intensity measurement by the electric field intensity measurement unit 250 is performed simultaneously with the demodulation of the biological information by the demodulation unit 240 . As a result, the radio wave state can be measured without interrupting monitoring of biological information.

Further, according to the present embodiment, the amplifier 220 for amplifying the signals from the antennas AN1 and AN2 is provided on the front stage side of the demodulation unit 240 and the electric field strength measurement unit 250, and the demodulation unit 240 and the electric field strength measurement unit 250 share the same amplifier 220 (in other words, receive signals from the same amplifier 220). As a result, compared to a system in which an electric field strength measuring unit is provided outside the central monitor 100 to measure the electric field strength, for example, the part that amplifies the signal when viewed as a whole system as much as the amplifier is shared. configuration can be simplified.

Further, according to the present embodiment, the distributor 230 for distributing the signals from the antennas AN1 and AN2 is provided on the upstream side of the demodulator 240 and the electric field strength measurement unit 250, and the demodulator 240 and the electric field strength measurement unit 230 are provided. The units 250 share the same distributor 230 (in other words, receive signals from the same distributor 220). This eliminates the need to separately provide a distributor as compared with, for example, a system in which an electric field strength measuring unit is provided outside the central monitor 100 to measure the electric field strength, so that the configuration can be simplified.

Incidentally, in the present embodiment, distribution of antenna signals to demodulation section 240 and distribution of antenna signals to electric field strength measurement section 250 by distributor 230 are the same. For example, when the signal of the antenna AN1 is distributed to the demodulator 240, the signal of the antenna AN1 is also distributed to the electric field strength measurement unit 250. FIG. This is because the antenna signal whose electric field strength is to be measured must be the same as the antenna signal to be demodulated.

The above-described embodiments are merely examples of specific implementations of the present invention, and the technical scope of the present invention should not be construed to be limited by these. Thus, the invention may be embodied in various forms without departing from its spirit or essential characteristics.

In the above-described embodiments, the case where the present invention is applied to a central monitor has been described, but the present invention is not limited to this, and in short, demodulates a plurality of biological information wirelessly sent from a plurality of biological information acquisition terminals. It is widely applicable to biological information monitors that display

INDUSTRIAL APPLICABILITY The present invention does not require a spectrum analyzer as an external measuring instrument, and has the effect of being able to measure the radio wave state regardless of the status of biological information monitoring, and is suitable for, for example, a central monitor.

10 biological information monitoring system 20 (20-1 to 20-n) bedside monitor 30 (30-1 to 30-m) telemeter transmitter 100 central monitor 110 biological information analysis unit 120 display control unit 130 alarm control unit 140 display Section 150 Alarm Indicator 170 Control Section 180 Operation Section 190 Barcode Reader 200 Receiving Section 210 Band Pass Filter (BPF)
220 Amplifier (AMP)
230 distributor 240 demodulator 250 electric field strength measurement unit 260 radio control unit 270 conversion circuit AN1, AN2-1, AN2-2, AN2-3 antenna AR1 electric field strength measurement selection area AR2 electric field strength graph area AR3 band selection area AR4 antenna selection Area AR5 Scan start position adjustment area

Claims (4)

a demodulation unit having a plurality of demodulation circuits that respectively demodulate a plurality of biological information wirelessly transmitted from a plurality of biological information acquisition terminals;
an electric field intensity measurement unit provided separately from the demodulation unit for measuring electric field intensity in a medical telemetry band including at least all frequency bands demodulated by the demodulation unit;
vital signs monitor. The measurement of the electric field strength by the electric field strength measurement unit is performed simultaneously with the demodulation of the biological information by the demodulation unit.
The vital information monitor according to claim 1. An amplifier for amplifying a signal from an antenna is provided on the preceding stage side of the demodulation unit and the electric field strength measurement unit,
The demodulation unit and the electric field strength measurement unit share the same amplifier,
The vital information monitor according to claim 1 or 2. A distributor for distributing a signal from the antenna is provided on the preceding stage side of the demodulation unit and the electric field strength measurement unit,
The demodulation unit and the electric field strength measurement unit share the same distributor,
The vital information monitor according to any one of claims 1 to 3.

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