Measuring multiple physiological parameters of the wireless terminal medical monitoring system

Multi-parameter monitor is important in clinical nursing unit, it can monitor the patient ECG, blood pressure, oxygen saturation, pulse rate, respiratory rate and temperature, and other physiological parameters. At present, domestic universal use with CRT or LCD displays have a portable monitor, this instrument is capable of performing real-time data and waveform display and operations more flexible, so it is used primarily to help doctors diagnose and analyze the patient's condition. However, due to its large, power consumption is high (add 220V AC or built-in current), it is not easy for patients to carry, even cannot simultaneously on multiple patients care. This article is designed for wireless distributed medical monitoring system will leave no stone unturned to compensate for the inadequate. The system with three separate OEM modules for measuring physiological parameters, each module separately and a wireless transceiver function control display module connected to constitute a separate device, so each module in a significant reduction of power consumption, which are correspondingly reduced. Patients can choose according to the different needs of different modules, each module on the LCD screen can be displayed measurement signal correctly. All of these modules with PC for wireless information exchange, PC can give each module registers a unique serial number, and you can access the information for each module, the information store, analysis, display, press q, etc, this is easily achieved many modules extend that to achieve this more real-time monitoring of patients. 1 system structure and working principle of the system is mainly composed of hardware and software, two-part. Hardware including PC and three independent modules that the module ECG module, oxygen and blood pressure modules, each of these three modules are controlled by the OEM module and show transmission modules. ECG module mainly used to measure ECG, respiration rate, body temperature, and other parameters; oxygen module mainly used to measure the blood oxygen saturation and pulse rate, and other parameters; oxygen module mainly used to measure oxygen saturation and pulse rate, and other parameters; blood pressure module used to measure blood pressure parameters. Software parts mainly PC central monitoring software, including databases and user interfaces. Figure 1 is a wireless terminal medical monitoring system structure diagram. Figure 1, the OEM module and PC through wireless transmission module for serial port communications to exchange information. The OEM module acquisition of data on PC for processing after being stored. Users can be in central monitoring software interface, select any of the modules view real-time acquisition to data or waveform, software can automatically analysed the data, unusual alarm signal in a timely manner. 2 the module functions and features 2.1 control displays the transfer module control displays the transfer module to Atmega161 microcontroller core, an external graphic LCD module WGM-12864, press and NRF903 wireless transceiver modules. Its circuit structure as shown in Figure 2. Atmega161 is Atmel company produced a low-power CMOS 8-bit single chip RISC, its performance 1MIPS/MHz, 16K bytes of FLASH, 512 bytes of EEPROM, 1K bytes of memory, 35 common i/o port, 32 universal working registers, three timers, internal and external interrupt sources, two programmable SPI port UART, and three by the software-selected power-saving mode. WGM-12864B module is a monochrome graphic dot matrix LCD display module, dot-matrix is 64 x 128. Its 8-bit data line and the mouths of PA Atmega161, D/I indicates that the data bus on the number of signals is dot-matrix or control command words, R/W indicates that the current operation is a read or write operation, E is the control-side, RST is reset client, CS1, CS2 was around lattice district elections end. PC1, PC2, PB1, PB0 to function keys and LCD together to form the menu style of human-computer interaction interface, control the corresponding OEM module. In work mode LCD displays from OEM module Gets the information of related data. NRF903 module is a wireless transceiver modules. NRF903 is a NORDIC company launched single-chip wireless transmit/receive one chip that uses Bluetooth (Bluetooth) core technology and design, a 32 foot chip includes a three-stage high frequency emission, high-frequency receiver, PLL synthesizer, I/Q modulator, I/Q demodulator, multiple channel switching, asynchronous communication interface, its programming interface CFG_CLK (configuration registers clock), CFG_DATA (configuration registers data), CS (configuration registers pieces selected) and SPI port Atmega161 PB7 (SCK), PB5 (MOSI), PB4 (SS) connected to the operating frequency, channel, output power and output clock frequency and other parameters to program settings. Set CS to high level, from 14-bit microcomputer control word in each CFG_CLK programming mode clock signal rising edge, CFG_DATA end logical value written to the configuration register, the programming information is loaded, the parameter is set to complete. STBY, Atmega161 PWR_DWN respectively and PD6, of, you can set PD5 as a standby or power-down mode. Data interface for DATA and a UART1 mouth Atmega161, used to receive and send data. TXEN feet and connected to PD7, used to control the sending and receiving of data. 2.2 ECG OEM module ECG OEM module adopts Beijing multran Tong Yuan electronic instrument co., Ltd of BT007 seven channel ECG strips. BT007 to automatically measure the human heart radio, respiration, heart rate, respiration, etc, body temperature, and other parameters, has the following characteristics: synchronization seven channel heart radio, four programmable gain, three-level filtering mode (diagnostic mode, guardianship, surgery), Bo pulse suppression feature, leads off the alarm, heart rate range 20-250BPM, defibrillation and electric knife interference, impedance respiration, respiratory rate range: 5-99BPM; dual temperature measuring, measuring range 0-50 ℃, the display precision 0.1 ℃, measurement accuracy 0.2 ℃. Communication with the user interface and UART serial port, there are two communication protocols: synchronize three-channel synchronous ECG Protocol and seven passChannel ECG Protocol, you can choose via jumper. Synchronize three-channel ECG Protocol features: 19200 baud, 8 data bits, 1 start bit, stop bit, no parity bit; synchronization seven channel ECG Protocol features: 28800 baud, 8 data bits, 1 start bit, stop bit, no parity. You can send to the MCU control word for the module, control the gain, filtering mode ECG; ECG plate data sent to the MCU to 1 byte header and a number of bytes of data as a group, the group header is sent, which is 251-254, digital byte is 0 ~ 250. MCU can categorize the data storage, analysis, display and transmission to the PC in real time. 2.3 oxygen oxygen OEM OEM module module using Beijing multran Tong Yuan electronic instrument co., Ltd of DIGISAT g1b module. The module via the UART TTL port for communication with MCU. It can provide the following data: arterial oxygen saturation, pulse rate, volume scanning, bar graph, signal strength and status information. Its communication protocols and BCI communications protocol compatibility, data transfer, the transfer to the baud rate 4800bps format: 8-bit data + odd routing baud rate, transmission format for 4800bps: 8-bit data + parity bit + 1 stop bit. The MCU per second sent 60 packets and each packet is 5 bytes. 2.4 OEM OEM module blood blood pressure module using Beijing multran Tong Yuan electronic instrument co., Ltd of BTN602 noninvasive blood pressure measurement module. The module also TTL level of UART port to communicate with the UCM. To receive an external command, complete the appropriate operation, and returns the system status and corresponding data. Data format: start bit + 8 data bits + 1 stop bit, no parity, baud rate 4800bps. 3 software system design – central monitoring software the software using VC language design. In the past with the hospital management system, in accordance with the principle of unified standards, enabling a new combination of old system, fully guarantee the original system of independent reliability, modular software architecture and refactoring. The system administrator will first need to be patient information manual input to your computer system in which critical information saved to a central database server; then key in the database data, statistics and classification. According to the category of the data is replicated to all sectors of care center database, when you start monitoring needs, start-to-patient wards and records. Patient monitoring data and alarm level can be adjusted according to the care you need. Query, display key data and images, and the key to query data in a memo, image annotation, you can batch print output key data and image files. Its software system structure as shown in Figure 3. System security controls mainly from three aspects to guarantee the security of your database, image file security, user security permissions. Built on the NT Server on a database server SQL Server enables users and database operations staff login to authenticate. Only use a database user account and password for the login of the user to manage and maintain the database, users on different tables with different levels of permissions. File server uses port control access, guarantee the security of the file server. System software through wireless transceiver modules, using polling of data acquisition module, the low end if system in query timed patient information, skip this module queries, the query into other modules, the software records the query failures, when query failures exceeds a certain threshold, the system issues a warning signal.