LoRa Flipbooks

p. 5 There are three main connectivity methods that should be considered for IoMT: Wi-Fi, Bluetooth, and LPWAN. Connectivity can be embedded within the device or added on with external modules and devices once the device has been deployed. Market expectations are that new smart devices have connectivity embedded within the device. Gateways can also be used to collect data on a local level then manage the connection to a cloud server for the transmission of this data. In this way, not every device or sensor must be connected to a cloud or network server. The following sections describe these wireless technologies and provide important aspects of and considerations for each in regard to the IoMT. Enterprise Wi-Fi Wi-Fi, in general, is a technology that uses radio waves to transmit information at specific frequencies. It enables high-speed and secure communication between a variety of devices, without wires, over both short and long distances within the Enterprise. In this white paper, we discuss Enterprise-grade Wi-Fi (versus consumer-grade) because it provides a higher-level of service when it comes to performance, security, standards/ compliance, and life-cycle management – factors that are important for connectivity in a healthcare environment. For devices and applications to be deployed within acute care (hospitals) or ambulatory care (clinical), Enterprise Wi-Fi is the primary wireless connectivity for local area networks. Another critical performance criterion in these environments is fast, secure roaming. Dropping network connectivity while a device is moving within these environments could create critical loss of data and delays to administrating healthcare to a patient. Your Wi-Fi module must support optimized scanning algorithms to maintain network persistence for the mobile device within these noisy RF environments. Enterprise Wi-Fi supports two communication bands. It is important to consider if the devices will be transmitting in the 2.4 GHz and 5 GHz bands. Since the 2.4 GHz band can quickly be congested with commodity devices and guest access, most hospitals have dedicated the 5 GHz band for critical devices and applications. There is increased bandwidth and performance available within the 5 GHz bands versus 2.4 GHz. Let's take a closer look at the latest Wi- Fi standards to further explain this. 802.11ac – The Standard of Choice for Enterprise Wi-Fi Although there are several Wi-Fi standards currently on the market, 802.11ac Wave 2 (or Wi-Fi 5) is the standard to pursue if you're actively introducing a device with embedded Wi-Fi. Wave 2 is not an official IEEE standard, but products classified as Wave 2 perform better and have additional features over 802.11ac Wave 1 (for example, MU-MIMO). 802.11ac includes significant enhancements to the Wi-Fi standard such as 80 MHz/160 MHz channels and MU-MIMO (multiple user – multiple input, multiple output) 802.11ac operates in the 5 GHz signal range which decreases interference common to 2.4 GHz and allows for the wider channel implementation. At the same time, 802.11ac devices are backward-compatible with the previous 802.11a and 802.11n 5 GHz devices. Also, most 802.11ac dual-band access points support 802.11b/g/n in the 2.4 GHz band. 80 MHz and 160 MHz Channels 802.11ac brings support for larger channel widths than previously. It's this increase in channel widths (80 MHz and 160 MHz) that primarily drives the enhanced performance and bandwidth. Previously, the general method to denote 5 GHz channels was to use the 20 MHz center channel frequencies for both 20 MHz and 40 MHz wide channels. With 802.11ac, we now reference the center frequency for the entire 20, 40, 80, or 160 MHz-wide channels. This gives us the following channels numbers for each specific channel width: (See Figure A) Understanding Connectivity Technologies 36 40 44 48 52 56 60 64 68 72 76 80 84 88 92 96 100 104 108 112 116 120 124 128 132 136 140 144 148 153 157 161 165 169 173 177 181 UNII-1 UNII-2 UNII-2 UNII-3 5150 MHz 5250 MHz 5350 MHz 5470 MHz 5725 MHz 5825 MHz 5925 MHz 20 MHz 40 MHz 80 MHz 160 MHz IEEE Channel# Currently Available New Channels Next Channels FCC: 5 GHz Channel Plan - Snapshot as of January 2015 Figure A

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