Smartphone Wireless - Revision history

Tom: /* Use Cases */

2022-05-20T20:16:49Z

‎Use Cases

Tom: /* BLE */

2021-11-11T18:16:48Z

‎BLE

Tom: /* BLE */

2021-05-23T17:22:55Z

‎BLE

Tom: /* BLE */

2021-05-23T17:22:10Z

‎BLE

Tom: /* BLE */

2021-03-24T03:59:03Z

‎BLE

Tom: /* NFC */

2021-01-27T00:08:03Z

‎NFC

Tom: /* BLE */

2021-01-27T00:05:02Z

‎BLE

Tom: /* BLE */

2021-01-27T00:03:42Z

‎BLE

Tom: /* BLE */

2021-01-27T00:01:01Z

‎BLE

Tom: /* BLE */

2021-01-27T00:00:35Z

‎BLE

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 * Originally just used 2.4 GHz now also uses 5 GHz
 It can be seen that the 2.4 GHz band is widely used for other applications including microwave ovens (as a result of the signal absorption in water) as well as Bluetooth, and many other wireless communications applications. Sometimes using other bands can improve the WLAN performance as a result of the lower interference levels.
 ==Use Cases==
 ===Contact Tracing===
-uses Bluetooth as it’s the most widely available technology. Bluetooth Low Energy devices are designed to be always on and, as the name implies, use very little battery. Depending on the scenario you can add in extra power management tricks. i.e. if there’s no accelerometer changes for many minutes, or contacts are constant, then you’re probably at home in bed, so check much less often for ‘contacts’. Wearables take this approach for example. Depending if you’re trying to “accurately measure risk” or “detect a contact or not” determines the level of data you need, and thus your scanning frequency. Generally though these apps will register a ‘background service’ - this enables the app user interface and non-bluetooth components to be removed from memory, and only the network contacts/logging to operate. This saves battery consumption. 1-2% battery per hour, depending on age of device, is usual. That’s approx half the battery use of WhatsApp just sitting in the background!
+uses Bluetooth as it’s the most widely available technology. Bluetooth Low Energy devices are designed to be always on and, as the name implies, use very little battery. Depending on the scenario you can add in extra power management tricks. i.e., if there’s no accelerometer changes for many minutes, or contacts are constant, then you’re probably at home in bed, so check much less often for ‘contacts’. Wearables take this approach for example. Depending if you’re trying to “accurately measure risk” or “detect a contact or not” determines the level of data you need, and thus your scanning frequency. Generally though these apps will register a ‘background service’ - this enables the app user interface and non-Bluetooth components to be removed from memory, and only the network contacts/logging to operate. This saves battery consumption. 1-2% battery per hour, depending on age of device, is usual. That’s approx. half the battery use of WhatsApp just sitting in the background!
 ==References==
 [[Category: Glossary]]

@@ Line 32: / Line 32: @@
 ===BLE===
-Bluetooth low energy + battery powered
+[[Bluetooth]] low energy + battery powered
 * Also excited by a stationary antenna that causes the smartphone to respond
 * Needs to have an app on a smartphone that is powered up and has bluetooth enabled that responds to the message with a UUID

@@ Line 38: / Line 38: @@
 * It is easy to test the range of BLE by seeing [https://blog.nordicsemi.com/getconnected/things-you-should-know-about-bluetooth-range how far away from the the phone an ear bud will work].  Typically that is about one room away.
 * [https://github.com/vmware/herald-analysis/tree/develop/reference-data/rssi-raw-edison Here is some raw data on testing BLE]
-* [https://developer.apple.com/library/archive/documentation/NetworkingInternetWeb/Conceptual/CoreBluetooth_concepts/CoreBluetoothOverview/CoreBluetoothOverview.html BLE connections in ISO 18013-5] between mDL and reader, but security sessions are not required. The mDL can enable either peripheral or central roles.
+* [https://developer.apple.com/library/archive/documentation/NetworkingInternetWeb/Conceptual/CoreBluetooth_concepts/CoreBluetoothOverview/CoreBluetoothOverview.html BLE connections may be used in ISO 18013-5] between mDL and reader, but security sessions are not required. The mDL can enable either peripheral or central roles.
 ===WiFi===

@@ Line 38: / Line 38: @@
 * It is easy to test the range of BLE by seeing [https://blog.nordicsemi.com/getconnected/things-you-should-know-about-bluetooth-range how far away from the the phone an ear bud will work].  Typically that is about one room away.
 * [https://github.com/vmware/herald-analysis/tree/develop/reference-data/rssi-raw-edison Here is some raw data on testing BLE]
 ===WiFi===

@@ Line 37: / Line 37: @@
 * Operations at 2.4 GHz at about 70 meters between device and antenna.
 * It is easy to test the range of BLE by seeing [https://blog.nordicsemi.com/getconnected/things-you-should-know-about-bluetooth-range how far away from the the phone an ear bud will work].  Typically that is about one room away.
 ===WiFi===

@@ Line 29: / Line 29: @@
 * Smart card with build in antenna
 * 13.56 MHz
 ===BLE===