CN106888428B

CN106888428B - Bluetooth-based data transmission method between intelligent terminal and medical wearable device

Info

Publication number: CN106888428B
Application number: CN201710188113.2A
Authority: CN
Inventors: 王韬; 张高瀚
Original assignee: Peking University
Current assignee: Peking University
Priority date: 2017-03-27
Filing date: 2017-03-27
Publication date: 2020-02-11
Anticipated expiration: 2037-03-27
Also published as: CN106888428A

Abstract

The invention discloses a transmission method between an intelligent terminal based on Bluetooth and a medical wearable device, wherein the medical wearable device comprises a processing module, a temporary storage module, a Bluetooth module and various sensors; each sensor sends data to the processing module through a serial port, the processing module controls writing and reading of the temporary storage module, and data transmission is carried out between the Bluetooth module and the intelligent terminal; according to the invention, through the data temporary storage, the two-way timestamp and the data retransmission method, when the Bluetooth transmission range is temporarily exceeded between the intelligent terminal and the medical wearable equipment and then the intelligent terminal and the medical wearable equipment return to the range, the physiological signal data is reliably transmitted between the intelligent terminal and the medical wearable equipment; when the Bluetooth transmission range is temporarily exceeded between the intelligent terminal and a patient (medical wearable device) and the intelligent terminal returns to the range, the physiological signal data transmission requirement can be met.

Description

Bluetooth-based data transmission method between intelligent terminal and medical wearable device

Technical Field

The invention belongs to the technical field of data transmission, relates to a physiological signal data transmission technology between an intelligent terminal and a medical wearable device, and particularly relates to a reliable data transmission method between the intelligent terminal (such as a smart phone) and the medical wearable device based on Bluetooth, which can meet the requirements of less data, more data, less data and more time sequence, and can be used for a sleep apnea syndrome detection system.

Background

The medical wearable device may be applied in the detection of various diseases. A typical remote monitoring system collects physiological signal data of a medical wearable device using a smartphone and then sends the physiological signal data to a remote data center. Doctors can check the physiological signal data of patients in the data center and diagnose the illness state of the patients through data indexes in specific time periods. Therefore, the physiological signal data needs to meet the requirements of not more, not less, not wrong and not disordered.

The invention patent CN106175772A discloses a sleep apnea monitoring system, which adopts a nose paste form and comprises a plurality of temperature sensors arranged in nostrils and/or mouths, and is connected with a microprocessor through a signal conditioning module, and the microprocessor is in data interaction with an intelligent terminal through a Bluetooth communication module. Adopt above-mentioned technical scheme data collection, when intelligent terminal and patient's short time surpassed the bluetooth transmission range and got back to the within range again, probably caused data loss and time sequence disorder. The prior art is difficult to solve the reliability problem of bluetooth data transmission between a microprocessor and an intelligent terminal, and the acquired physiological signal data are difficult to meet the requirements of not more, not less, not wrong and not disordered in time sequence.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a reliable transmission method between a Bluetooth-based intelligent terminal and a medical wearable device, and the reliable transmission method can ensure that when the intelligent terminal (such as a mobile phone) is away from the wearable device for a short time and returns to the Bluetooth transmission range again, the reliable transmission of physiological signal data can meet the requirements of not more, not less, not wrong and not disordered in time sequence.

For convenience, the definition convention of related terms of the present invention is as follows:

sensor package (SDP): the sensor packages the acquired physiological signal data according to a specific format, called SDP, according to its sampling rate. Wearable equipment has multiple different sensors, also has multiple different SDPs, and according to different physiological index requirements, the data volume that different SDPs contain is different.

Bluetooth packet (BTP): and after receiving the SDP, the processing module sends the SDP through Bluetooth. When data is transmitted through Bluetooth, the method of the invention is adopted to pack the data further, which is called BTP. Each BTP may contain one or more SDPs, while each BTP contains only SDPs for the same type of sensor for accuracy of the parsed data. Thus, the length of each BTP is not the same.

A packet header field: to identify the beginning of a BTP, a specific data sequence is needed to find out where an exact BTP begins.

Escape byte: in order to avoid the resolution problem caused by coincidence between the specific data sequence and the normal physiological signal data, if a specific data sequence happens to appear in the normal data, an escape byte needs to be added to prevent confusion.

Relative time stamping: the method is generated by a processing module in the medical wearable device, a hardware clock is arranged in the processing module, a counter accurate to a microsecond level can be generated, the processing module is not connected with the Internet, therefore, the processing module can only generate relative time stamps relative to the starting point of power-on, and each SDP is generated by writing a relative time stamp into the processing module.

Absolute time stamp: an intelligent terminal (mobile phone) acquires absolute time (such as 0 minute and 0 second at 8 am on 1 month and 1 day in 2017) from the internet, and matches the first relative timestamp with the first absolute timestamp, and then calculates to obtain the absolute time generated by each SDP; the technology of the bidirectional time stamp can ensure that physiological signal data does not generate offset and the time sequence is not disordered when being stored.

The technical scheme provided by the invention is as follows:

a reliable transmission method between an intelligent terminal based on Bluetooth and a medical wearable device is disclosed, wherein the medical wearable device comprises a processing module, a temporary storage module, a Bluetooth module and a plurality of sensors; each sensor comprises one or more sensors; each sensor has a set of serial numbers; each sensor sends data to the processing module through a serial port, the processing module controls writing and reading of the temporary storage module, and data transmission is carried out between the Bluetooth module and the intelligent terminal; the reliable transmission method realizes the reliable transmission of the physiological signal data between the intelligent terminal and the medical wearable equipment through data temporary storage, two-way time stamping and a data retransmission method; when the Bluetooth transmission range is temporarily exceeded between the intelligent terminal and a patient (medical wearable device) and the intelligent terminal returns to the range, the requirements of less, more, less, not wrong and not disordered physiological signal data can be met; the transmission method comprises the following steps:

A. a processing module in the medical wearable device assembles data of the sensors into an SDP, and assembles multiple SDPs of the same type into a BTP. The realization method comprises the following steps:

A1. and each sensor in the medical wearable equipment sends data to the processing module through the RS232 serial port according to the format of the sensor packet.

A2. A processing module in the medical wearable device collects data of each sensor in a classified manner, adds a relative timestamp to the data of each sensor, assembles the data into SDP, and stores each SDP into a temporary storage module; the temporary storage module is used for setting a temporary storage queue for each type of sensor, and SDPs from the same type of sensors are stored in the same temporary storage queue.

A3. The processing module checks each type of temporary storage queue in the temporary storage module at regular time, when the data volume of one type of temporary storage queue reaches the specified requirement or meets the requirement of data retransmission, the processing module takes out one or more SDPs (the higher the real-time requirement is, the higher the sampling rate of the sensor, the length of each SDP and the real-time property of the sensor requirement is, the higher the real-time property requirement is, the quantity is properly reduced so as to send out the data more quickly), and the BTP is assembled into a BTP according to the protocol format of the BTP (a packet header field, a type field, a sequence number, the length of the BTP and a CRC checksum are added to the BTP). Specifically, each sensor has a respective set of serial numbers, and when a sensor generates a new SDP, the serial number corresponding to that sensor is incremented.

B. The medical wearable device and the intelligent terminal transmit physiological signal data through Bluetooth, and the accurate time stamp of each SDP in BTP successfully received by the intelligent terminal is determined, wherein the accurate time stamp comprises a relative time stamp and an absolute time stamp. The realization method comprises the following steps:

B1. the data of BTP are sent to intelligent terminal through the bluetooth to the wearable equipment of medical treatment.

B2. And when receiving the BTP, the intelligent terminal analyzes data according to the protocol format of the BTP. More specifically, the starting position of the BTP is found according to the header field, a BTP range is identified according to the BTP length, the integrity of the BTP is judged according to the CRC checksum, the sensor type of the BTP is identified according to the type field, and the SDP in the BTP corresponds to the SDP according to the serial number.

B3. After the intelligent terminal analyzes the BTP, if the CRC checksum passes the check and the serial number is the same as the serial number waiting for receiving, replying the corresponding BTP to the medical wearable equipment to successfully receive; and if the checksum does not pass the verification or the serial number does not match the serial number waiting to be received, replying to the medical wearable device that the receiving is unsuccessful. Particularly, if the receiving is successful and the BTP is the first BTP received by the intelligent terminal, the intelligent terminal analyzes the relative timestamp of the last SDP in the BTP and records the absolute timestamp at the moment, and according to the sampling rate of the type of sensor, the relative timestamp (X0) and the absolute timestamp (Y0) of the first SDP in the BTP are calculated and matched with each other to serve as the base point of the two-way timestamp; when the intelligent terminal successfully receives the subsequent BTP, the relative timestamp (Xi) of each SDP in the BTP can be calculated to obtain the absolute timestamp (Yi ═ Y0+ Xi-X0) of the SDP.

B4. If the medical wearable device receives a response that the BTP of a certain type is successfully received, deleting the SDP contained in the BTP from the temporary storage queue of the corresponding type; if the medical wearable device receives some type of BTP unsuccessfully, or does not receive a reply within a certain time, the method returns to step a3, and performs data retransmission until the reception is successful.

In the embodiment of the present invention, the processing module is an FPGA (Field-Programmable Gate Array); the temporary storage module is a Random-Access Memory (RAM) or an external Secure Digital (SD) Memory card; the SDP timestamp is 4 bytes, accurate to milliseconds.

Compared with the prior art, the invention has the beneficial effects that:

by the Bluetooth-based reliable transmission method between the intelligent terminal and the medical wearable device, the problem of reliability of Bluetooth data transmission between the medical wearable device and the intelligent terminal is effectively solved. When the intelligent terminal and the patient temporarily exceed the Bluetooth transmission range and then return to the range, the physiological signal data can meet the requirements of not more, not less, not wrong and not disordered in time sequence through the data temporary storage module, the two-way timestamp technology and the data retransmission scheme.

Drawings

Fig. 1 is a block diagram of a remote monitoring system according to an embodiment of the present invention.

Fig. 2 is a flow chart of a transmission method provided by the present invention.

Detailed Description

The invention will be further described by way of examples, without in any way limiting the scope of the invention, with reference to the accompanying drawings.

The invention aims to provide a reliable transmission method between an intelligent terminal and a medical wearable device based on Bluetooth, which can be used for reliably transmitting physiological signal data between the intelligent terminal and the medical wearable device in a sleep apnea syndrome detection system, and can ensure that the data meet the requirements of not more, not less, not wrong and not disordered in time sequence when the intelligent terminal and the medical wearable device are temporarily far away and return to the transmission range, and the time sequence of the physiological signal data in transmission is not disordered.

Reliable transmission generally includes "not much", "not wrong" and "not out of order" requirements, wherein the "not out of order" requirement, such as trying to see the physiological data map of a patient between 1 and 2 points in the morning, needs to record the generation time of each kind of physiological signal data, and ensure that the timing is not out of order when the data is retransmitted.

The technical solution in the embodiment of the present invention is clearly and completely described below with reference to the accompanying drawings. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without inventive step, are within the scope of the present invention.

Fig. 1 is a block diagram of a remote monitoring system according to an embodiment of the present invention. As shown in fig. 1, the medical wearable device includes various sensors, and in the sleep apnea syndrome of the present embodiment, the sensors include a blood oxygen sensor, an electrocardiograph sensor, and an electroencephalogram sensor. Each sensor sends data to processing module through RS232 serial port protocol, writes into the module of keeping in with data earlier by processing module, reads out data from the module of keeping in when satisfying a certain data bulk or needing the retransmission, and rethread bluetooth module carries out data transmission with the smart mobile phone.

Fig. 2 is a flow chart of a transmission method provided by the present invention, and the transmission method includes the following steps:

B. The medical wearable device and the intelligent terminal transmit physiological signal data through Bluetooth, and the accurate time stamp of each data is determined. The realization method comprises the following steps:

B4. If the medical wearable device receives a response that the BTP of a certain type is successfully received, deleting the SDP contained in the BTP from the temporary storage queue of the corresponding type; if the medical wearable device receives a certain type of BTP unsuccessfully, or does not receive a reply within a certain time, a certain amount of SDPs need to be taken out from the temporary storage queue of the corresponding type again to be assembled into BTPs for data retransmission.

Wherein, the processing module is an FPGA (Field-Programmable Gate Array); the temporary storage module is a Random-Access Memory (RAM) or an external Secure Digital (SD) Memory card; the time stamp of the SDP is 4 bytes and is accurate to millisecond; escape byte is 0 xFF; the packet header field of the BTP is 1 byte and is determined as 0 xFE; the BTP type is 1 byte and can represent over 200 different sensors; the sequence number of BTP is 2 bytes, the most significant bit of each byte is not used (set to 0) to avoid collision with escape byte and packet header field, the total significant bit number of the sequence number is 14 bits, and the maximum number can represent 2 ¹⁴Serial numbers and can be recycled; the BTP has a length of 4 bytes, the most significant bit of each byte is not used (set to 0) so as to avoid collision with escape bytes and packet header fields, the total significant bit of the BTP has 28 bits, and the maximum significant bit can represent 2 ²⁸A length of one byte; the data content of the BTP is N SDPs, the value of N depends on the sampling rate of the sensor, the length of each SDP and the real-time performance required by the sensor, and the higher the real-time performance requirement is, the value of N isShould be reduced appropriately to send out data faster; table 1 is the format of SDP.

TABLE 1 SDP Format

1 st to 4 th bytes	Beginning at byte 5
		SDP time stamp	SDP data content

TABLE 2 format of BDP

Byte 1	2 nd byte	Bytes 3 to 4	Byte 5 to 8	Beginning at byte 9	Last two bytes
						Header field	Type (B)	Serial number	Length of BTP	BTP data content	CRC checksum

Table 2 is the format of the BDP. The checksum of BTP is the last two bytes, and a CRC check mode is adopted.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive efforts by those skilled in the art based on the technical solution of the present invention.

Claims

1. A data transmission method between an intelligent terminal based on Bluetooth and a medical wearable device comprises a processing module, a temporary storage module, a Bluetooth module and a plurality of sensors; each sensor comprises one or more sensors; each sensor has a set of serial numbers; each sensor sends data to the processing module through a serial port, the processing module controls writing and reading of the temporary storage module, and data transmission is carried out between the Bluetooth module and the intelligent terminal; the transmission method realizes reliable transmission of physiological signal data between the intelligent terminal and the medical wearable device through data temporary storage, bidirectional timestamp and data retransmission methods, and ensures that the time sequence of the physiological signal data in transmission is not disordered; the transmission method comprises the following steps:

A. a processing module in the medical wearable device assembles data of the sensors into sensor packages SDP, and stores each SDP into a temporary storage queue of a corresponding type of a temporary storage module; the processing module assembles one or more SDP packages of the same type into a Bluetooth package BTP; the method specifically comprises the following steps of obtaining the Bluetooth packet BTP:

A1. each sensor in the medical wearable equipment sends data to a processing module through a serial port according to the format of a sensor package SDP;

A2. a processing module in the medical wearable device collects data of each sensor in a classified manner, adds a relative timestamp to the data of each sensor, assembles the data into SDPs, and stores each SDP into a temporary storage queue of a corresponding type of a temporary storage module;

A3. the processing module checks various types of temporary storage queues in the temporary storage module at regular time, and when the data volume of one type of temporary storage queue reaches the specified requirement or meets the requirement of data retransmission, the processing module takes out one or more SDPs in the temporary storage queue and assembles the SDPs into a BTP by adding the protocol format of the BTP;

B. the medical wearable device and the intelligent terminal transmit physiological signal data through Bluetooth, and the accurate time stamp of each BTP successfully received by the intelligent terminal is determined, wherein the accurate time stamp comprises a relative time stamp and an absolute time stamp; for each BTP successfully received, deleting SDP contained in the BTP from the temporary storage queue of the corresponding type; for each BTP which is not successfully received, a certain number of SDPs are taken out from the temporary storage queue of the corresponding type again to be assembled into BTPs, and data transmission is carried out again until the receiving is successful;

the following operations are specifically executed:

B1. the medical wearable device sends the BTP data to the intelligent terminal through Bluetooth;

B2. when receiving the BTP, the intelligent terminal analyzes data according to the protocol format of the BTP;

B3. after the intelligent terminal analyzes the BTP, if the checksum passes the inspection and the serial number is matched with the serial number waiting for receiving, replying the corresponding BTP to the medical wearable equipment to successfully receive the BTP; if the checksum does not pass the verification or the serial number does not match the serial number waiting for reception, the medical wearable device is replied to receive unsuccessfully; if the receiving is successful, recording the accurate time stamp of each SDP in the BTP, wherein the accurate time stamp comprises a relative time stamp and an absolute time stamp;

2. The transmission method as claimed in claim 1, wherein in step a3, the BTP field includes a packet header field, a type field, a sequence number field, a BTP length field, and a CRC checksum field.

3. The transmission method as claimed in claim 2, wherein each sensor has a set of serial numbers, and when a sensor generates a new SDP, the serial number of the sensor is incremented by one.

4. The transmission method as claimed in claim 1, wherein step B2 is to find the starting position of the BTP based on the header field, identify a BTP range based on the BTP length, determine the integrity of the BTP based on the CRC checksum, identify the sensor type of the BTP based on the type field, and identify the SDP in the BTP corresponding to the sequence number.

5. The method as claimed in claim 1, wherein the step B3 records the precise timestamp of each SDP in the BTP, and specifically: if the receiving is successful and the BTP is the first BTP received by the intelligent terminal, the intelligent terminal analyzes the relative timestamp of the last SDP in the BTP and records the absolute timestamp at the moment, and according to the sampling rate of the type of sensor, the relative timestamp and the absolute timestamp of the first SDP in the BTP are calculated and are respectively marked as X0 and Y0, and the two are matched with each other to be used as the base point of the two-way timestamp; when the intelligent terminal successfully receives the subsequent BTP, the absolute timestamp Yi of the SDP is calculated by Y0+ Xi-X0 according to the relative timestamp Xi of each SDP in the BTP.

6. The transmission method according to claim 1, wherein the processing module is a field programmable gate array.

7. The transmission method according to claim 1, wherein the temporary storage module is a Random Access Memory (RAM) or an external Secure Digital (SD) memory card.

8. The transmission method as claimed in claim 1, wherein the time stamp of the bluetooth packet SDP is 4 bytes accurate to milliseconds.