A research and development frenzy seems to have arisen around wireless healthcare applications, as they can make healthcare more convenient for everyone involved, extend healthcare to rural areas, improve efficiency, and more. A recent white paper from the Wi-Fi Alliance focuses specifically on the benefits of WiFi for hospitals, Titled “Wi-Fi in Healthcare: Improving the User Experience for Connected Hospital Applications and Devices,” the 16-page document re-affirms that connecting medical devices to a hospital WiFi network can improve clinical workflows by providing wireless access to real-time patient data. It then lays out how high quality-of-experience (QoE) levels can be maintained through network design, RF design, infrastructure and client-device configuration, and continuous management.
Most guides focus on quality of service (QoS). While QoS metrics measure network performance, however, this document asserts that QoE metrics expand QoS to assess how network performance translates into user experience. One issue, for example, is the multitude of devices used in the environment and their networking characteristics, performance capabilities, and requirements. Of course, RF propagation dynamics also come into play.
Although much of the paper provides information that is better suited for information-technology (IT) professionals, it offers some good basics to those newer to wireless-networking concerns. In the section on RF design in particular, it explains that WiFi network coverage is deemed adequate when signal strength—RSSI and/or signal-to-noise ratio (SNR)—permits a client device to establish and maintain a network connection that satisfies the device service-level agreement (SLA). Such a connection—and the ability to forge that connection—must be adequate everywhere in the coverage area. It also must be noted that client devices require varied levels of signal strength, depending on the type of device, the type of data that it transmits and receives, and the data rates required.
When it comes to real-world deployments, RF propagation challenges like physical obstructions, interference, and multipath effects obviously become an issue. Coverage will be required in bathrooms and procedure areas, for example, perhaps not taken into account during initial network planning. Such areas also present more complex RF environments. The key is that a detailed analysis must note the devices to be used and how they will be used in different areas. With good analysis as a basis, WiFi network design can be tailored to provide the required signal levels for RF coverage for every area while offering a buffer against propagation challenges.
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