20

Wireless and Bluetooth are very close technologies. But, when to choose between one of them you have to consider many things. Speed: Bluetooth 4.0 offers 25 Mbps while WiFi Direct can offer you 250 Mbps. So if you want a faster transfer rate, i.e. if you need to transfer large amount of data within a short time, and it is your main concern, go for WiFi. ...


13

If you can have end-to-end TCP, then use end-to-end TLS (e.g. with HTTPS). Don't reinvent the wheel, especially when it comes to cryptography — most people get it wrong. Unless the device is too resource-constrained to support TLS, if you get down to the level of AES, you're doing it wrong. #1 mistake is to encrypt and forget to authenticate — if you have ...


13

To ensure that your device is secure enough, I have several tips: Add some encryption to the Bluetooth communication. I'd recommend keeping the encryption keys off air. For example, you might ask the user to scan a QR code that's on the device, on printed in the box etc. at the initial setup of mobile app, maybe with an AES key? Up to you. This is to ...


10

Bluetooth Classic: If line power is available, and the application is a data intensive application such as audio streaming Bluetooth Low Energy: If the data rate is low and device is powered by battery. Wifi: Base on current available technology, if line power is available and application requires large amount of data. So for a smart home device, user base, ...


8

No, CoAP is an application layer protocol it's not dependent Basically that's the beauty behind the OSI layers. If correctly implemented you can mostly stack them however you want. As with every thing that starts with if correctly implemented that's mostly academic and some protocols fit better together with others than others do. More or less the only ...


8

From the perspective of power usage, Bluetooth 3.0 does not seem like a viable choice, given your constraints. Let us assume that you want to transmit data for 2 seconds every minute, and then sleep for the rest of the time. Given your range requirements of 30 metres, you will likely need to use a Class 1 Bluetooth Radio: Class 1, primarily for ...


7

Basically, you trade off bandwidth, range and cost. If one of the choices does not meet your requirements for bandwidth or range, then your choice is clear. If both meet those requirements, then it is a business decision, and you would probably go with cost. Of course, this implies that you are providing both client and server. If you are, for instance, ...


7

Building your own device for this use case really is the wrong approach. The industrial design to build something that will survive day to day use and be comfortable to wear with a useable battery life is likely to take longer than the study you want to run. Just buy an off the shelf fitness tracker. There are plenty that have open BLE interfaces. But if ...


6

I would recommend some sort of mesh network, as obviously plain old WiFi or BT won't cover those distances. Zigbee is as good a candidate as any. For hardware, AdaFruit does some good wearables, although if everyone has a smartphone, you might as well use those. And, if you can figure out how to power it by battery, take a look at my answer to this ...


6

Have you looked at Web Bluetooth? This can be used to write to the the device without needing a native client app just to set the time. There is support in Chrome on most platforms and other browsers are adding support. I've been working on a device that uses Web Bluetooth to set the wifi details (the device is a clock that will use NTP to remain accurate ...


6

Since you don't intend to further communicate with the partner device I guess the precision of the set time is okay for you in a precision range of a few seconds. If you want to get more precise you'll have to take a lot more into consideration (delays, latency, lower level protocols and the like). In general BLE is a communications protocol, you can access ...


6

I'm not sure why you're checking for z's and so on but your first else if clause ensures that none of the clauses in the rest of the block is ever executed. else if (state != 'z' && state!=0) { digitalWrite(ledG, LOW);} // turn the LED off by making the voltage LOW When state is any value that's neither z nor 0 (x, y, etc) then this block is ...


6

Apple is keeping the technology it uses for AirPods under wraps, hence my answer is best attempt based on the information in public domain. Do both Airpods use Bluetooth technology? Yes, because Power efficiency that Airpods come with can be achieved via Bluetooth. Airpods are inter-operable with Android and Windows, this proves Apple has used standards ...


6

I have document some aspect of BLE low power aspects as a response to What is the difference between Bluetooth Low Energy and Bluetooth BR/EDR in Park mode?. Here are is a suggestion. Looks like a SIM808 has a serial interface. So I suggest integrate the SIM808 module with a Dual Mode Class 1 BLE such as KC-5170. I think you could use a single mode BLE too. ...


6

Another factor to consider is radio packet size, which is much smaller for Bluetooth than for WiFi. This means that the collision risk is lower for Bluetooth than for WiFi, and a Bluetooth transmission is more likely to disrupt a WiFi transmission than vice versa.


6

Summary The actual protocol used doesn't matter—many smart devices connect to the Internet of Things using ZigBee, Z-Wave, Bluetooth or another protocol via a gateway which then connects the devices to the Internet. Many would say that a device which isn't controllable or accessible via the Internet is not an Internet of Things device, however; it's not ...


6

Assuming it is Bluetooth (a fair guess as this is the only other radio that is regularly available in mobile phones/tablets), then it will be Bluetooth 4 which will be advertising a BLE Service that has a known set of Characteristics. The app running on the phone/tablet will connect to the BLE Service, query a Characteristic for what WiFi SSIDs the device ...


5

I have reached a conclusion that the Bluetooth will be a better choice with its upcoming new release of Bluetooth 5. Reference. Kirkland, Washington – June 16, 2016 – The Bluetooth Special Interest Group (SIG) announced that its next release, coming late 2016 to early 2017, will be called Bluetooth 5 and will include significantly increased range, speed, ...


5

Alternatively it might be worth to consider wireless Hart (Highway Addressable Remote Transducer). This is a 2.4GHz ( license free frequency band) Smart mesh networking technology that uses 802.15.4 standard. WHart use direct-sequence spread spectrum technology and needs at minimum three main components. Namely wireless devices, gateway and network manager. ...


5

As is often the case, it depends. There are many factors to consider, and a lot of options available to cover the many different use cases around. Range DigiKey suggest that you can expect the following ranges for common IoT protocols in an unobstructed environment with little interference: 5 GHz Wi-Fi: 50 m ZigBee/RF4CE: 100 m Bluetooth low energy: 100 m 2....


5

SIMCOM SIM808 module seems to meet the requirements for your device. Bluetooth: compliant with 3.0+EDR Specification for GPS Receiver type 22 tracking /66 acquisition -channel GPS L1 C/A code Sensitivity Tracking: -165 dBm Cold starts : -147 dBm Time-To-First-Fix Cold starts: 30s (typ.) Hot starts: ...


4

That is one of the many problems with IoT devices: The operating systems are proprietary, and you do not have root access to them. Furthermore, disabling kernel modules is generally too complex for most users. Additionally there's a large number of models, and updates typically stops before the end of life for the product, leading to unpatched code in the ...


4

I would recommend you look at building your own custom device and log locally to it, either in a CSV format or something higher grade with better compressibility such as FIT. Then do file transfers periodically and parse your data either on the device either in the cloud or on the phone. A nRF52 microcontroller that has a built-in BLE/ANT radio and is ...


4

AFAIK you cannot do that. Thinking of Bluetooth as a quite complex protocol of approximately 1k pages of documentation the power electronics to build such circuit would be overly sized. Think of your PC, it inputs 110 or 220 and still there is the power unit that lowers the voltage to low DC as in every micro circuit you see nowadays.


4

The short answer is yes. Power line voltage of 110-220 VAC needs to be step down to a lower DC voltage such as 5VDC or 3.3VDC depending to overall device power requirement. Most Bluetooth module require a 5VDC or 3.3VDC to operate. The device will have a microcontroller, a Bluetooth module and some type of control circuitry to controlling an external device ...


4

For iOS users, an option to disable "Find Your Phone" was added in Tile v2.28.1. Open the Tile device list Press ... on a tile and select Edit Tile Details Under Actions, unselect the option for Find Your Phone Unfortunately, this feature is currently not available for Android users.


4

It looks like a pretty standard Bluetooth Low Energy (BLE) device so assuming the manufacturer hasn't done something strange (e.g. like fitbit) then you should be able to use any language that has BLE GATT support to connect to the device and then subscribe to the characteristics for each of the different data fields. For NodeJS there is the noble which is ...


3

It seems that there is no direct access to the necessary memory, that is, there is no function to write to the global index, but I found a way to change the device name. You can use this function ConnectionChangeLocalName (8, (uint8 *) "My_Name").Bluetooth began to show up under the name My_Name, and the local device name changed to linvor in PSTool.


3

Look at TI/Energia Launchpad and SimpleLink line. CC3220 or MPS432. There are Bluetooth options and a pretty good set of software. Link to Texas Instruments CC3220S-LAUNCHXL site. This board has a built in temperature sensor and accelerometer, so it's fun to play with. SimpleLink™ Wi-Fi® CC3220S Wireless Microcontroller LaunchPad™ Development Kit Link to ...


3

You have the options of either using an activity service based on an existing device (i.e. a phone), or reverse engineering an existing device (fitbit or derivative). This is well established technology, you're likely to find some patented ideas, and some open source code relating to the signal processing. The actual sensor ought not to be posing a ...


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