Bluetooth experience - got any??

[Faz10]

Dunno whether this is the right forum to post this on, but I'm curious to find out what experience if any, people have with bluetooth.

Any good reliable URLs would be appreciated as well - the official bluetooth site isn't up to much on indicating joe public market trends - just at analyst level and that isn't much good to me.

Your opinions would be appreciated.

 

[telcomwork]

I can't remeber where I learned some of this stuff but it was intresting enough when considering wireless technologies. Bluetooth uses short-range radio frequencies to transmit both voice and data. This technology wirelessly synchronizes data across devices and creates access to networks and the Internet within a range of ten meters.
The Bluetooth specification is perfect for mobile users who need to connect notebook computers, cell phones, PDAs, digital cameras...at home, on the road, or in the office. It works using an unlicensed radio frequency band.It was developed by the Bluetooth Special Interest Group in 1998. The Institute of Electrical and Electronics Engineers (IEEE) is currently converting the specification into an IEEE standard; this is known as the IEEE 802.15 standard. Bluetooth radios operate in the unlicensed ISM (Industrial Scientific Medical) band at 2.4 GHz and employ frequency-hopping (FH) spread spectrum technology to reduce interference and fading. A Time-Division Duplex (TDD) scheme is used for full-duplex transmission. Bluetooth's main strength is its ability to simultaneously handle both data and voice transmissions.The Bluetooth Wirless Personal Area Networking (WPAN) consists of up to eight active devices, with one hub and up to seven client devices. A Bluetooth WPAN is capable of supporting an asynchronous data link with each client and synchronous voice links with up to three client devices. It provides a range of up to 10m at a transmit power of 1 mwatt. The range can be extended to 100m if the transmit power is increased to 100 mwatt. Bluetooth has a data rate of 1 Mbps. Multiple Bluetooth units form a Wireless Personal Area Network, called a piconet. A piconet consists of a hub device and up to seven clients. It's possible to have more devices in a piconet by placing one or more of the clients into what is referred to as park mode. In order to exchange information with the parked client, the hub must take it out of parked mode and return it to active mode. Only seven clients can be in active mode at any given time.When two piconets are in close proximity, they have overlapping coverage areas - a scenario referred to as a scatternet. Clients in one piconet can participate in another piconet as either a hub or client. This is accomplished through time division on multiplexing. In a scatternet, the two or more piconets are not synchronized in either time or frequency. Bluetooth device can only be a hub in one piconet, since the piconet is defined by the hub's Bluetooth address. Each of the piconets operates in its own frequency-hopping channel, while any devices in multiple piconets participate at the appropriate time via time division multiplexing. The RF channels used for Bluetooth are from 2402 to 2480 MHz, with a channel spacing of 1 MHz. The Bluetooth radio hops from channel to channel at 1600 hops per second, which means that every 625 msec. Each piconet has a unique hopping sequence, which is determined using an algorithm based on the address of the Bluetooth hub. All Bluetooth units in the piconet are synchronized to this hopping sequence.The Bluetooth Baseband Layer: The baseband layer performs functions like Bluetooth packet assembly, forward error correction (FEC), automatic repeat request (ARQ), data whitening, Bluetooth clock synchronization, and frequency hopping control.The Bluetooth Link Manager Layer: The Link Manager forms the piconet by inquiring what other Bluetooth radios are in the area, establishing connection and maintaining the piconet. The Link Manager also handles security issues like authentication and encryption.
Bluetooth is primarily a wireless personal area networking technology, coupled with IEEE 802.11a and 802.11b based LANs without impeading on them. For short-range, personal communication, Bluetooth is a great technology.

 

[Faz10]

Blimey, that's a lot of technical information which I'll have a read through - thanks very much, it should be v. useful. However, I'm predominantly interested in whether people think it's got much of a future. I think personally it's the dogs b***ks, but I'm not exactly a big ticket spender. Thanks Milletary.

 

[telcomwork]

No problem. My personal opinion, I think the 802.11 standards have more of a future in the grand scheme of wireless networking. It will be interesting to see to what magnitude and how fast 802.11a will catch on. Bluetooth seems great for adhoc'ing and simplier designs but for Wireless LANs, I think we'll see more from IEEE 802.11 standard. Just my opinion, could be wrong. I have only been in the field for 4 years so maybe some of the vets in the group can expand on general trends and the coming of standards they have seen over the years.

 

[Loon]

The real Bluetooth market looks like it might be integration with mobile/celluar phones. Such devices are certainly being developed, and should enable phones to exchange information within a few metres as well as sustaining a voice/data call.

Not sure if it will take off but I agree with Miletary, I think 802.11 will become the standard in Wireless LANs.

Cheers
Loon

 

[murtoz]

The problem with bluetooth is all the different profiles... isdn, dial-up networking, lan, serial, obex, etc etc... Two bluetooth devices arfe not necessarily compatible unless they support the same profile.. and that can get annoying.
It works a treat when 2 devices are compatible though
Also, it is a great competitor of 802.11(a or b) where it concerns power consumption.
It might still have a future, but maybe just for simple devices... i'd quite like a phone with it's own ip...