無線健身和醫療監控系統的連通性選項

　　由于健身監視器今天風靡一時，無線連接有許多不同的選擇。針對消費者的健身帶使用的是藍牙低能量連接到智能手機的最新版本，但也有許多其他方式提供連接到健身帶，也作為一個無線病人監護儀。

　　作為傳感器平臺本質上是相同的心跳和血壓監測添加到一般的運動跟蹤，長距離低功耗的無線鏈路可以提供顯著更長的電池壽命為帶，減少了需要補給系統，使更完整的數據捕獲能力。這些可以與網關，它提供了一個恒定的鏈接，而不是依賴于手機的連接，提供了一個更可靠和完整的數據收集架構。這種可靠的無線鏈路變得越來越重要，因為數據可以直接發送到云存儲和分析，而不是被下載時從顯示器充電時。

　　As medical and fitness monitors do not require high data rate connections， the wireless link bandwidth can be traded for longer range and lower battery life， allowing significantly more data collection before the monitor needs recharging.

　　The Flex Gecko family of wireless controllers from Silicon Labs provides both 868 MHz sub-GHz and 2.4 GHz connectivity with the necessary encryption to protect the data. The 868 MHz links provide a long-range capability to link to a gateway for the collection of data. The chip combines an ARM? Cortex?-M4 controller core， 256 kB Flash， 32 kB RAM and 31 digital I/O pins to link to sensors as well as seven 16-bit timers and multiple communication interfaces. The transmitter provides a 20 dBm maximum output power and a receive sensitivity of -121 dBm at 2.4 kbps， using 2 GFSK encoding and a 0.1% bit error rate （BER）。 There are multiple low-power modes for different levels of operation that help to keep the power consumption to a minimum. This is particularly useful in a medical monitoring device that will wake up every few minutes to take readings and transmit them to the gateway， and then go back into an ultra-low power sleep mode. Figure 1 shows the different power modes， where the majority of the chip is kept dormant until required to transmit or receive data.