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Bluetooth Technology
Overview
A few years ago, the telecommunications and
computing industries recognized that a truly low-cost, low-power
radio based cable replacement, or wireless link, was feasible. Such
a ubiquitous link would provide the basis for small portable devices
to communicate together in an ad-hoc fashion. A study was performed,
and the technology code named "Bluetooth" began to be
defined. The goal was to provide effortless service for mobile and
business users by means of a small, short range radio-based technology
for integration into production line models of a range of different
devices.
The result will be a refined specification for a technology that
optimizes the usage model of all mobile computing and communications
devices, delivering:
* voice and data handling
* global usage
* ability to establish ad-hoc connections
* ability to withstand interference from other sources in open band
* very small size to accommodate integration into variety of devices
* negligible power consumption in comparison to devices
* open standard
* very low cost
Technology Characteristics*
Bluetooth will be specifically designed to provide low-cost, robust,
efficient, high capacity, ad hoc voice and data networking with
the following characteristics:
* 1Ms/s symbol rate exploits maximum available channel bandwidth
* Fast frequency hopping avoids interference
* Adaptive output power minimizes interference
* Short data packets maximize capacity during interference
* Fast acknowledge allows low coding overhead for links
* CVSD (Continuous Variable Slope Delta Modulation) voice coding
enables operation at high bit-error rates
* Flexible packet types supports wide application range
* Relaxed link budget supports low-cost single chip integration
* Air interface tailored to minimize current consumption
These features will enable Bluetooth to provide extremely flexible
and high data rate links even in the presence of severe interference.
In addition to performing without sacrificing the performance level
achieved when signal conditions are good, as the interference increases
the performance degradation will remain minimal and gradual, enabling
stable links to be maintained.
Basic Technical Information*
* Based upon a small, high performance integrated radio transceiver,
each of which is allocated a unique 48-bit address derived from
the IEEE 802 standard.
* Operate in the unrestricted 2.45GHz ISM 'free band', which is
available globally although slight variation of location and width
of band apply
* Range set at 10m to optimize for target market of mobile and business
user
* Gross data rate 1Mbit/s, with second generation plans to increase
to 2 Mbit/s
* One-to-one connections allow maximum data transfer rate of 721
kbits/s (3 voice channels)
* Uses packet switching protocol based on frequency hop scheme with
1600 hops/s to enable high performance in noisy radio environments.
The entire available frequency spectrum is used with 79 hops of
1Mhz bandwidth, analogous to the IEEE 802.11 standard
* Low power consumption drawing only 0.3mA in standby mode enables
maximum performance longevity for battery powered devices. During
data transfer the maximum current drain is 30mA. However during
pauses or at lower data rates the drain will be lower
Technical Specifications*
Receiver
RX sensitivity
-70dBm
IP 3
-16dBm
CP 1 dB
-6dBm
Double-sided IF bandwidth
1.0MHz
C/I co-channel (0.1% BER)
11dB
C/I 1MHz (0.1% BER)
-8dB
C/I Š 2MHz (0.1% BER)
-40dB
C/I AWGN (0.1% BER)
18dB
In-band image rejection
20dB
Transmitter
TX power:
* nominal
0dBm
* optional range
-30 - +20dBm
Modulation index (no ISI)
0.28-0.35
TX carrier offset
<75kHz
Adjacent channel power
(1MHz) -20dBm
Out of band spuriouses
50dB
Power control requirements: optional range
-30 - +20dB
Frequency Sources
Symbol timing accuracy
20ppm
L 500kHz
-89dBc/Hz
L Š 2MHz
-121dBc/Hz
Channel-switching time
220µs
TX/RX turnaround time
220µs
General
Antenna diversity
NA
Operating environment when applicable
IEEE802.11
*Features currently planned are subject to change without notice.
Actual features may vary.
For more information about Bluetooth, visit
www.bluetooth.com.
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