bluetooth adapters for any car radio?
Introduction to Bluetooth
|Look for this logo on all Bluetooth wireless technology enabled products.|
Most people are familiar with Bluetooth through their mobile phones. It’s used to wirelessly connect a smartphone to a vehicle’s audio system, and wireless Bluetooth headsets are becoming commonplace. But Bluetooth wireless technology has expanded far beyond those initial applications. Bluetooth is used to connect portable music players to speakers, smartphones to home theater receivers, and tablets to car audio systems.
|Smartphone accessories such as the Bose® Bluetooth® headset Series 2 are gaining in popularity.|
Typically, devices with Bluetooth technology have a range of about 30 feet. Because Bluetooth operates on radio frequencies, the signal can pass through walls and clothing. So you can stream music from your smartphone to a speaker system in another room, or take calls through a Bluetooth headset from your phone in your jacket pocket.
Many Bluetooth applications (especially those involving phones) are used in public spaces, so wireless security can be a concern. Bluetooth has built-in security protocols, so you don’t have to select encryption or create network passwords. Bluetooth uses adaptive frequency hopping (AFH) to skip between its allotted 79 frequencies 1,600 times a second, making it almost impossible to intercept a transmission.
Pairing and connecting
Thanks to the standardization brought by the Bluetooth SIG (a professional trade association overseeing the use of the technology), setting up and configuring Bluetooth-enabled devices is fairly straightforward. It involves little more than getting the two devices you want to connect close to each other and turning them on. You don’t have to install drivers or software, either. Any two wireless products with Bluetooth technology, regardless of brand or country of origin, have the capability to communicate with one another.
The first step is to “pair” the devices. Make sure both devices are on, and use the sender (smartphone, tablet, PDA) to find the receiver (portable speaker, car stereo head unit, home theater component receiver) in it’s menu of detected Bluetooth devices. Selecting it causes the two devices to be paired – the sender knows where to send its signals, and receiver recognizes the sender as a signal source.
Pairing devices is usually a one-time procedure. The devices should remember and automatically find each other. And usually you can pair a device with up to eight different products. That can be handy for devices that get used by several people. Consider a car shared by four members of a family – each with their own smartphone. Every family member can pair their phone to the car’s audio system once, and the system will accept connections from all four devices.
|The Dual XDMA6630 is Bluetooth enabled, and comes with front USB port for wired connectivity.|
Although you can pair multiple devices, you can only make a one-on-one connection to use both devices. For example, when you select what paired device you want to play your PDA’s music through on its menu, you make a connection. The signal streams to the device, and you hear the music. Even though your smartphone may also be paired to the device, it can’t make a connection to it as long as the PDA is wirelessly connected.
Going back to our example of the family car, if one person is making a hands-free call through the car system, then the other three family members have to wait until the call is completed and connection broken before one of them can connect to the system and use it for their call.
|The Parrot CK3000 Evolution car kit can make just about any car receiver Bluetooth-compatible.|
One of the most common applications of Bluetooth is hands-free mobile phone operation. Almost every mobile phone produced has built-in Bluetooth. Pair your phone with a Bluetooth headset, and you can talk while your phone is still in your pocket or purse. Many car stereos also have built-in Bluetooth for hands-free calling in your vehicle. And if necessary, you can retrofit your car stereo system with a Bluetooth car kit.
|The portable Soundmatters foxLv2 Platinum Bluetooth wireless speaker system is almost as compact as your smartphone.|
Wireless music streaming
Bluetooth can be found in many portables, such as tablets, portable game consoles, PDAs, smartphones – and even laptops. Portable Bluetooth speakers and desktop speaker systems let you stream audio from these devices without needing to make a wired connection. And since any audio your device plays can be streamed, you can enjoy not just the songs stored on your player, but also Internet radio stations, online music services, as well as soundtracks from videos and games.
Ever use a wireless keyboard or mouse? They you’ve already experienced Bluetooth in action. Some wireless printers also use Bluetooth. And of course you can pair Bluetooth wireless speakers with your Bluetooth-enabled computer as well.
Bluetooth Profiles (and why they matter)
The capabilities for Bluetooth continue to expand. While all versions of Bluetooth share the same basic functionality, more advanced versions that can stream uncompressed audio and video can only be found in certain devices.
All versions (or “profiles” as they’re called) of Bluetooth are backward compatible, so can send music from a Bluetooth 3.0 device to a Bluetooth 2.0 speaker. The thing to remember, though, is that the connection is made through the lower Bluetooth profile. So while your device may have the capacity to send 24MB per second, if the speaker can only handle a 10th of that, then that’s what your device will send – with a corresponding loss of audio quality.
This was the first Bluetooth profile, launched in 1999. It was primarily used for mobile phones.
Data transfer rate: 1MB per second
Bluetooth 2004 was ratified in 2004, and represented a significant improvement in performance and sound quality. It was sometimes offered as Bluetooth 2.0+EDR. EDR (Enhanced Data Rate) ensured a faster transfer by making the signal carry data more efficiently. The first iPhone® and early Android™ phones used Bluetooth 2.1.
Data transfer rate: 2.1MB per second
Data transfer rate w/EDR: 3MB per second
This wider bandwidth Bluetooth profile was adopted in 2009. Because its data transfer rate was 10 times that of 2.1, more than just audio could be transmitted without significant delay. Bluetooth 3.0 has the bandwidth to send images, videos and uncompressed audio. This is the profile used by wireless printers and high-performance Bluetooth speaker systems. Bluetooth 3.0+HS (High Speed) modifies the protocol slightly to send smaller data packets at a faster rate, further reducing lag time.
Data transfer rate: 24MB per second
This profile was adopted in 2010. In one sense, it’s a return to the much simpler Bluetooth 1.0 in terms of capacity (although actual transfer rates aren’t published). But there’s a very important difference. Bluetooth 4.0 takes very little power to operate. So now glucose monitors, pedometers, digital watches, and other small devices that use coin-cell batteries can be Bluetooth-enabled. Most of the applications for Bluetooth 4.0 are for devices with simple data link. So, for example, with Bluetooth 4.0 your heart rate monitor can send data wirelessly to your computer.
For more information about Bluetooth wireless technology, visit the Official Bluetooth Wireless Info Site.