Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [bluetooth]

A low bandwidth, low-power short-range wireless protocol typically used for personal area networks that operates on 2.4GHZ-2.485GHZ.

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Is Bluetooth Communication Possible Without Pairing?

I am working on a device which can wirelessly activate a system "instantly". The first thing which came to mind was to use RFID technology which has the advantage of instant and cheap communication. However, I am interested in using my phone's…
capcom
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Does Bluetooth interfere with WiFi?

I've read that WiFi b/g/n is using 2.3995 to 2.4845 GHz. Bluetooth is in between: 2.4000 to 2.4835 GHz. So what will happen when I put a Bluetooth sending device next to a WiFi sending device? Will the two devices be aware of each other (like two…
zomega
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How to synchronize two microcontrollers to micro-second accuracy?

I need to synchronize two micro-controllers so that they can measure the speed of propagating waves. The time delay measurements need have microsecond accuracy (error less that 1/2 of a microsecond). I have two micro-controllers (ATmega328) which…
Kevin
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Why 2.4 GHz Band?

Bluetooth, WiFi, Zigbee, Remote Controls, Alarms, Cordless Phones etc.. Why all of these protocols, devices, etc. use 2.4 GHz band instead of 3.14 GHz. What is so special about it?
cbr
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Electronic pet-door access control - RFID

Inspired by projects such as the tweeting cat door and CATaLOG [sic] I’m wanting to add some form of automated access control to our pet door to control who can go in and out, when. (Full Disclosure: This is a reprint from my blog where I first…
Evan
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Bluetooth HID Module

I am trying to implement my own Bluetooth HID device (a kind of custom game controller), but am having trouble finding what I am looking for. I have only come across two solutions which seem slightly expensive to me based on the task. The two…
piepi
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Options for short range distance determination between two objects

I have a project idea in mind, but it involves calculating the distance between two people. I've looked into Bluetooth, RFID, and NFC (unsure about this one), but none appear to offer the accuracy I would need (I am a novice at best, so I would…
Ryan
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Low Cost Bluetooth

What is the lowest cost way to add a Bluetooth integrated radio to an embedded system? I am using a BlueGiga WT12 which works well. IIRC these are in the $20-$25 range. Are there comparable modules that are less expensive? For example, I've also…
jluciani
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Wireless communication between more than two Microchip PIC microcontrollers

I would like to create wireless communication between Microchip PICs for my simple project. It's actually an one way communication but there is one server and more than one client (about 2-4, all client needs to the same number at the same time, so…
Felician
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Should the unused areas on the top layer of my RF PCB have ground pours?

I realize there are some questions that are related to this topic but I didn't see any that are really RF specific. I am working on a 2-layer Bluetooth module and I have some unused spaces on the top layer that I can't decide if they should be…
DigitalNinja
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Broadcast audio to multiple receivers via Bluetooth

I want to be able to connect multiple Bluetooth devices to a Bluetooth transmitter, and then stream audio from a portable MP3 player, via Bluetooth, to all of the connected Bluetooth receivers. Is this even possible? I thought of using the A2DP…
Johnny
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Does higher dBi mean further range, for an antenna?

I recently purchased this (ridiculously expensive) Bluetooth module for my Arduino from SparkFun. On the item's page it says that it has been tested at 100 m. I contacted SparkFun for info about their setup and they said to achieve the 100 m range…
Sponge Bob
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Streaming video using BLE or classic Bluetooth 4.0?

BLE only has a data payload of 100Kbps so I was wondering if it is possible to stream a live video using Bluetooth Low Energy? Classic Bluetooth 4.0 has a data payload of 2Mbps which makes it easier to transmit the video but I am more concern about…
Electronic Curious
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What Bluetooth 4.0 devices and radios are available?

Bluetooth 4.0 is the latest specification to be adopted by the Bluetooth cabal, which notably adds Bluetooth low energy into the mix, which is designed to allow radios that sip battery like 802.15.4 ("ZigBee") to directly connect to consumer…
Nick T
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BLE Scan interval and window

With Bluetooth Low Energy, you specify a scan window (how long to scan) and interval (how long to wait between scans). Would there be any difference between scanning for 10 ms every 100 ms, or scanning for 1 sec every 10 sec? Seems like the chance…
Maestro
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