JPS5894832A - Waveform transmitting system - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission method for transmitting signal waveforms of various information using wireless lines, and is particularly suitable for transmitting signal waveforms from a transmitting side to a receiving side using weak radio waves. This paper relates to a waveform transmission method.

The case of transmitting, for example, a biological signal as a signal waveform will be explained using FIG. 1 as an example. Conventionally, as shown in FIG. 1, a signal is picked up by a human body.

Biological signals such as electrocardiogram, respiration, and blood pressure waveforms obtained by attaching sensors and transducers are level-adjusted in the amplification unit 1, and then output as modulated input signals to the wireless transmission unit 2.
The wireless transmitter 2 modulates the signal and transmits it to a receiving center (nursing station, etc.) using weak radio waves. At this time, the weak radio wave transmitted from the wireless transmitter 2 is an output that does not require reapplication for authorization, and has a reachable distance of 1oon.
+ level, and is mainly used in hospital buildings.

Note that the center on the receiving side receives the transmitted radio waves and reproduces and monitors the biological waveform on a monitor.

However, although such a conventional transmission system has the advantage of a simple configuration, since it is an analog transmission in addition to a weak radio wave, there is a lot of ambient noise KIl, which impairs the reliability of the transmitted waveform.

Furthermore, since biological signals need to be continuously monitored in real time, they must be transmitted continuously, which increases power consumption.

Furthermore, one channel (carrier frequency) is required to transmit one item of waveform for continuous transmission, resulting in poor transmission efficiency.Moreover, if one of the transmitting and receiving ends is a centralized facility, the receiving device can receive biological signals. Item branch l! There were drawbacks such as:

The present invention was made to eliminate the above-mentioned conventional drawbacks, and detects the amplitude of an input signal waveform at a constant novel,
By sampling only the input signal that exceeds that level at a frequency based on the sampling theorem, encoding the digital data, and transmitting the waveform using a digital method, it is possible to improve noise resistance against surrounding noise, and to generate intermittent waveforms. The present invention provides a waveform transmission method that can reduce power consumption and improve transmission efficiency per channel by utilizing idle time for intermittent transmission.

Hereinafter, the present invention will be explained in detail using the drawings.

*2 Figure is a block diagram showing an embodiment of the waveform transmission system according to the present invention. In the figure, an amplifier section 11 adjusts a biological signal as a 10-digit input signal to a predetermined level, an A-D converter section 11 converts the output signal of the amplifier section 10 into digital data according to a sampling clock φl, and 12 FiA-D.
Buffer 7 section 13 inputs the digital data of conversion section 11 and temporarily stores the data, takes in the data of buffer section 12 using the output clock φ4 of AND gate 17 as a starting signal, and transfers the data to a predetermined transmission format)K an encoding unit that encodes and outputs it in the form of a signal to, for example, F8;
14F! This is a wireless transmitter that modulates the output signal of the encoder 13 as a modulation input and transmits the signal using weak radio waves.

This is an amplitude detection section that judges the biological signals of 15 to a certain threshold level and outputs a @Hm (high level) signal while exceeding that value.The output signal is sent to the buffer section 12 and the logic It is input to the product gate 17 to control their operation. For the 16ti A-D converter 11, there is a sampling clock φl, and for the buffer unit 12, there is a clock that determines the data capture timing of the MuD converter 11 and controls data transfer within the buffer unit 12. 2. Logical product) 17 is a clock generating section that outputs a transmission control clock φ1 for controlling the operation of the encoding section 12, respectively.

Next, the operation of the above embodiment will be explained with reference to FIGS. 3 and 4. Here, the biological signal is adjusted to a predetermined level in an amplifying section 10, and then converted into digital data in an A/D converting section 11.

At this time, the conversion fHA- of the AD converter 11 is determined by the sampling clock φl, but this clock φ! The period of is set in advance according to the sampling theorem according to the frequency of the biological signal. However, in the case of intermittent waveforms such as biological signals shown in Figure 3, the signal waveforms generally exhibit rapid changes with respect to the sampling interval specified by the sampling theorem, and the conditions are no longer met. . Therefore, in this embodiment, a narrowly spaced sampling clock φ1 (see FIG. 4) necessary for reproducing the intermittent waveform shown in FIG. The amplitude of the intermittent waveform is detected by an amplitude detection section 15. Therefore, when the flat portion l of the intermittent waveform below a certain amplitude shown in FIG. Buffer section 12. Input to logical product game) 17. From this button,
Buff 7 part 12 #i, tx4 Figure (a) Flat part shown in K.
During period 1, as shown in FIG. 4(e) Ic, the clock -2 from the 1-clock generator 16 is not taken in, and the digital data storage operation of the A-D converter 11 is not performed. Also,
As shown in FIG. 4 (j), the transmission control clock φ4 from the clock generator 16 is not input, and there are 13 encoders.
No transfer operation is performed. Therefore, the data in the flat portion l shown in tiX4 diagram (a) is not transferred, and the unbalance between the sampling data accumulation rate and transmission rate can be adjusted by the idle time.

On the other hand, when the amplitude detection section 15 detects a waveform portion 4e2 of the intermittent waveform shown in FIG. , are input to the buffer section 12 and the AND gate 17. Then, the buffer section 1.2 receives the @H' signal from the amplitude detection section 10 as shown in FIG. 4(c).
A clock φ2 indicating K is taken in, and A-D
The digital data of the converter 11 is accumulated and held until the data is transmitted by the encoder 13. In the encoding unit 13, the clock φ generated from the clock generating unit 1B
3 (FIG. 4 (d) #/see) is gated by the AND gate 17 using the 1H" signal of the amplitude detection section 15 (.)
Following the clock φ4 indicated by
It is output to the wireless transmitter 14 in the form of an SK signal. As a result, if the wireless transmitter 14 modulates and transmits only the waveform portion of the intermittent waveform having a certain amplitude or more, the result is K. Note that the clock φ4 shown in FIG. 4(@)K is continuously sent to the encoding unit 13 from the start to the end of data transmission.

In this way, according to the transmission method of the above embodiment, when the amplitude detection section detects an input signal waveform with an amplitude above a certain level, only the part of the waveform above the certain amplitude is converted by the A-reconverting section and the digital data is buffered. If the data is temporarily stored in the buffer section and the waveform is transmitted at a predetermined transmission speed, and the data is stored in the buffer section and the waveform transmission operation is stopped for the flat waveform portion below a certain amplitude, then from K, the quantum of the intermittent waveform is This makes it possible to significantly reduce the amount of data associated with digitization, to perform intermittent transmission compatible with intermittent waveforms, and to enable digital waveform transmission.

As described above, according to the present invention, digital data transmission has a large margin against ambient noise, enables highly reliable waveform transmission, and eliminates the need for continuous transmission for one intermittent waveform, reducing power consumption. In addition, it becomes possible to transmit other items using the idle time of transmission. In addition, the ability to improve transmission efficiency per channel (carrier frequency) eliminates the need to have as many receivers as the number of channels on the centralized equipment side, simplifying the transmission system. effective.

[Brief explanation of drawings]

Figure 1 is a block diagram showing the transmitting side of a conventional waveform transmission system, Figure 2 is a block diagram showing an embodiment of the waveform transmission system of the present invention, and Figures 3 and 4 are explanations of the operation of Figure 2. This is a waveform section that is used for 10...Amplification section, 11...A-D conversion section, 12
...Buffer section, 13... Encoding section, 14...
...Radio transmitter, 15...Amplitude detector, 16...
・Clock generation section, 1T...AND gate. Patent applicant Hitachi Electronics Co., Ltd. Agent Masaki Yamakawa (1 person)

Claims (1)

[Claims] An amplifier section that adjusts the level of an input signal, an A-reconversion section that converts the output signal of the amplifier section into digital data,
an aircraft width detection unit that determines whether the input signal is below a certain amplitude and outputs a determination signal; a buffer unit that temporarily stores digital data from the A-D conversion unit using the output signal of the amplitude detection unit as a reference point; an encoding section that encodes the data in the buffer 7 section into a predetermined transmission format based on the output signal of the amplitude detection section and outputs the signal; and a modulation output signal that modulates the output signal of the encoding section as a modulation input. and a clock generating section that outputs a sampling clock for each of the A-D conversion sections, a data accumulation control clock for the buffer section, and a control clock for the encoding section. When the width detection section detects an amplitude below a certain amplitude of the input signal, the front buffer temporarily stores only the part of the waveform whose amplitude is above the certain amplitude, transmits the waveform at a predetermined transmission speed, and detects the constant amplitude of the input signal. Data is accumulated in the buffer section for the following flat waveform portion. A waveform transmission method characterized by stopping the waveform transmission operation.