Bell Laboratories Layer Space-Time (BLAST) is a
transceiver
In radio communication, a transceiver is an electronic device which is a combination of a radio ''trans''mitter and a re''ceiver'', hence the name. It can both transmit and receive radio waves using an antenna, for communication purposes. The ...
architecture for offering
spatial multiplexing
Spatial multiplexing or space-division multiplexing (often abbreviated SM, SDM or SMX) is a multiplexing technique in MIMO wireless communication, fibre-optic communication and other communications technologies used to transmit independent chan ...
over
multiple-antenna wireless communication
Wireless communication (or just wireless, when the context allows) is the transfer of information between two or more points without the use of an electrical conductor, optical fiber or other continuous guided medium for the transfer. The most ...
systems. Such systems have multiple antennas at both the transmitter and the receiver in an effort to exploit the many different paths between the two in a highly-
scattering wireless environment. BLAST was developed by
Gerard Foschini at
Lucent Technologies
Lucent Technologies, Inc. was an American multinational telecommunications equipment company headquartered in Murray Hill, New Jersey. It was established on September 30, 1996, through the divestiture of the former AT&T Technologies business u ...
'
Bell Laboratories
Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984),
then AT&T Bell Laboratories (1984–1996)
and Bell Labs Innovations (1996–2007),
is an American industrial research and scientific development company owned by mult ...
(now Nokia Bell Labs). By careful allocation of the data to be transmitted to the transmitting
antenna
Antenna ( antennas or antennae) may refer to:
Science and engineering
* Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g., TV or radio) waves
* Antennae Galaxies, the name of two collid ...
s, multiple
data stream
In connection-oriented communication, a data stream is the transmission of a sequence of digitally encoded coherent signals to convey information. Typically, the transmitted symbols are grouped into a series of packets.
Data streaming has b ...
s can be transmitted simultaneously within a single
frequency band
A frequency band is an interval in the frequency domain, delimited by a lower frequency and an upper frequency. The term may refer to a radio band or an interval of some other spectrum.
The frequency range of a system is the range over which i ...
— the
data capacity of the system then grows directly in line with the number of antennas (subject to certain assumptions). This represents a significant advance on current, single-antenna systems.
V-BLAST
V-BLAST (Vertical-Bell Laboratories Layered Space-Time) is a detection
algorithm
In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific Computational problem, problems or to perform a computation. Algorithms are used as specificat ...
to the receipt of multi-antenna
MIMO
In radio, multiple-input and multiple-output, or MIMO (), is a method for multiplying the capacity of a radio link using multiple transmission and receiving antennas to exploit multipath propagation. MIMO has become an essential element of wir ...
systems.
Available for the first time in 1996 at
Bell Laboratories
Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984),
then AT&T Bell Laboratories (1984–1996)
and Bell Labs Innovations (1996–2007),
is an American industrial research and scientific development company owned by mult ...
in New Jersey in the United States by
Gerard J. Foschini. He proceeded simply to eliminate interference caused successively issuers.
Its principle is quite simple: to make a first detection of the most powerful signal. It regenerates the received signal from this user from this decision. Then, the signal is regenerated subtracted from the received signal and, with this new signal, it proceeds to the detection of the second user's most powerful, since it has already cleared the first and so forth. What gives a vector containing received less interference.
The complete detection algorithm can be summarized as recursive as follows:
Initialize:
Recursive:
See also
*
Space–time code — a means for using multiple antennas to improve reliability rather than data-rate.
*
Telecommunication
Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that fe ...
References
Further reading
*
External links
* http://www.alcatel-lucent.com/wps/portal/BellLabs
Antennas
Detection theory
{{wireless-stub