Intelligent Hospital Data Acquisition and Transmission Solution

Project Background

Inpatient department patients require daily collection of vital signs data such as blood pressure, body temperature, and heart rate, which needs to be transmitted to the hospital data center to facilitate patient condition monitoring by doctors. However, the current manual measurement, recording, and monitoring processes are time-consuming and labor-intensive. Hospital layouts often involve multiple floors and complex room arrangements. Traditional wireless communication methods suffer from blind spots and interference issues.

^{Hospital Building and Floor Layout}

^{Hospital Single Floor and Functional Zones}

Formula for Calculating Wireless Signal Transmission Loss in Air:

Los = 32.44 + 20lg d(Km) + 20lg f(MHz)

Los is the transmission loss in dB. d is the distance in Km, and f is the operating frequency in MHz. It is evident that transmission loss is directly proportional to frequency. That is, the higher the frequency, the greater the transmission loss. Alternatively, under the same transmission loss condition, the transmission distance is inversely proportional to frequency. Meaning, the higher the frequency, the shorter the transmission distance.

✪  2.4G Frequency Signals:

Short transmission distance, significant attenuation during transmission, weak signal penetration and diffraction capabilities, signals are easily obstructed by objects.

• ZigBee

Operates in the 2.4G band, offers low data transmission rates, and focuses on low-data-rate applications. Single-node transmission distance is short, requires maintenance of transmission routes, routes need power supply, making it difficult to achieve ultra-low power consumption.

• WiFi

Operates in 2.4G or 5G bands, requires registration/authentication, offers wide transmission bandwidth. It is a technology based on Wireless Local Area Network (WLAN) interconnection and, like Bluetooth, belongs to short-range wireless communication technologies.

• Bluetooth Technology (including BLE)

Operates in the 2.4G band, has very short transmission range, requires registration/authentication, and is suitable for PC-peripheral device connections and minimal data transmission.

Thus, it is evident that the 2.4G frequency band is currently quite congested!!

✪ 433M and Adjacent Frequency Signals:

Long transmission distance, strong penetration and diffraction capabilities, relatively low attenuation during transmission.

• Star Topology Networking

Point-to-point or point-to-multipoint transmission methods, mostly using master-slave response transmission. Simple networking, reliable transmission. Not suitable for wide-area networking (Our company supports concurrent transmission for a limited number of nodes and a contention arbitration mechanism based on signal strength).

• Routing Networking

Networking method based on flooding mode, does not require route maintenance, data transmission has high redundancy, high probability of frame loss.

• Mesh Networking

Networking method based on path identification, featuring prominent characteristics like dynamic self-organization, self-configuration, and self-maintenance; technically challenging, effective transmission speed is low.

"Technical Requirements for Low-Power (Short-Range) Radio Equipment"

— Issued by the Ministry of Information Industry in 2005

A combination of star topology networking and wired transmission mode is required to balance distance and concurrency.

How can the concurrency of wired systems and the convenience of engineering construction be balanced?

Our Company's Data Transmission Bus: LBUS Data Transmission Bus Solution

The LBUS bus is a long-distance, multi-master communication fieldbus. Unlike RS485 and CAN bus, it uses an unbalanced transmission method, transmitting data while also supplying power to nodes. That is, using just two wires, it can both transmit data and supply power to nodes on the bus. This is similar to M-BUS, but unlike MBUS, it can provide currents up to 2A or more to nodes. Due to the unbalanced data transmission method, the bus can also be designed as a non-polarized bus.

The baud rate on the LBUS bus is determined by the arbiter. Each master automatically adapts to the bus baud rate and synchronizes automatically.

^{Differences between LBUS and Other Buses}

^{System Layout Diagram}

^{Wired Section Connection Diagram of the System}

Solution Implementation Principle

• The entire system consists of the LZBUS bus (including master and slave stations), 433M wireless nodes, and a local PC;

• The LZBUS communicates with the local PC via a serial port (managed on the local intranet, preventing data leakage). The master station communicates with each slave station via two wires. Each slave station is connected to a wireless data transmission module, communicating with the wireless nodes under its jurisdiction via the wireless module. Each slave station can communicate with its managed wireless nodes through address identification;

• If there is an overlapping communication area between wireless nodes managed by two adjacent slave stations, different working frequencies can be set for the wireless nodes under different slave stations. This way, even if adjacent slave stations simultaneously query their managed modules, wireless conflicts will not occur.

About Hainan West-HN Technology

Hainan West-HN Technology Co., Ltd., with the vision of "Making Standardization of Industrial IoT Simpler," focuses on the IoT industry chain. We continuously conduct R&D in indoor positioning, sensing control, and data transmission products, adopting a Lego-like production approach to precisely meet the small-volume, high-variety demand characteristics of industrial IoT products. We provide solutions for complex environments and personalized needs, truly achieving a new supply-demand relationship with low inventory and high satisfaction.

The company has R&D centers in Shanghai, Suzhou, Chengdu, and Taipei. Upholding the group's nearly 40 years of strong trade resources and reputation, we firmly believe in the business philosophy of "Being Experts in the Industry." We excel in channels, are sensitive to the market, focus on products, ensuring R&D results are reliable, production is stable, and sales maintain quality. We are always dedicated to the ultimate satisfaction of personalized scenario needs for industrial IoT customers.

Regarding products, we have both Zigbee positioning products developed by our in-house team over more than 10 years and UWB positioning products developed by teams in Shanghai and Taipei, meeting different customer requirements for positioning accuracy. Simultaneously, the company also introduces Bluetooth positioning products to complement our self-developed solutions, aiming to fully satisfy the needs of various customers.

In terms of software support, we integrate overall solutions from various industries, actively open interfaces and source code for system integrators to join, facilitating related software companies in creating case demonstrations based on our products, thereby broadening the application of IoT indoor positioning.

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