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Topic: Alamouti coding


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In the News (Tue 17 Nov 09)

  
  Space–time block code - Wikipedia, the free encyclopedia
Space–time block coding is a technique used in wireless communications to transmit multiple copies of a data stream across a number of antennas and to exploit the various received versions of the data to improve the reliability of data-transfer.
Its most serious disadvantage is that all but one of the codes that satisfy this criterion must sacrifice some proportion of their data rate (see Alamouti's code).
Alamouti invented the simplest of all the STBCs in 1998
en.wikipedia.org /wiki/Alamouti_coding   (1746 words)

  
 MIMO Wireless Communications
A block code is a code that operates on a "block" of data at a time and the output only depends on the current input bits.
There are other codes, such as "convolutional codes" whose output is dependant on the current input, and also on the previous inputs.
Since the Alamouti code is a full rate code there is no immediate increase in the data rate of the system.
www.eng.newcastle.edu.au /~c2104305/mimo.html   (1226 words)

  
 Transmitter diversity technique for wireless communications - Patent 6775329
A simple block coding arrangement is created with symbols transmitted over a plurality of transmit channels, in connection with coding that comprises only of simple arithmetic operations, such as negation and conjugation.
The sequence of codes is routed through a cycling switch that directs each code to the various antennas, in succession.
The problems of prior art systems are overcome, and an advance in the art is realized with a simple block coding arrangement where symbols are transmitted over a plurality of transmit channels and the coding comprises only of simple arithmetic operations, such as negation and conjugation.
www.freepatentsonline.com /6775329.html   (5204 words)

  
 Untitled Document   (Site not responding. Last check: 2007-11-02)
This is to be contrasted with the novel DST scheme with one relay proposed in [1], which is able to achieve full diversity by switching between cooperation using the Alamouti design and one-hop transmissions from the source to the destination based on the minimum error probability at the destination.
To enable distributed space-time coding the relaying/cooperating nodes must be synchronized, which increases overhead during the call setup procedure.
To this end our first step would be to investigate a source coding type problem in which the feedback rate is minimized provided that “sufficient” CSI is available at the transmitter.
www.ece.umn.edu /users/anghel/Main_files/overview.htm   (1761 words)

  
 ECE: Publications: Theses and Dissertations
Thus far, most work on space-time coding has focused on systems with small antenna arrays or high signal-to-noise ratios (SNRs), for which it has been shown that codes should be designed according to the rank and determinant criteria.
Although the codes designed according to the new design criterion achieve good performance, most of them require maximum-likelihood (ML) decoding, which is undesirable for high-rate codes.
For coherent detection, the coding structure is extended to non-unitary constellations.
www.ece.ncsu.edu /pubs/etd/id/etd-12122005-094358   (522 words)

  
 projinfo
Space-time coding is a recent technique not yet used in commercial systems where spatial diversity at the transmitter is exploited to create very reliable communication over a fading channel.
A common space-time orthogonal block code using two transmitters is the so-called Alamouti space-time code.
The data should be coded (Alamouti) and transmitted in packets over the channel.
www.s3.kth.se /signal/edu/projekt/students/01/grey/projinfo.htm   (653 words)

  
 MIMO Toolkit
Alamouti is a simple scheme that gives a 2nd order transmit diversity, it was one of the first space time code to be proposed.
The above diagram executes BPSK for Alamouti scheme in a 2 transmit and 2 receive antenna case.
The channel used is a Ricean channel with K factor of 1.
www.ece.utexas.edu /~rheath/research/mimo/labview/Alamouti.php   (134 words)

  
 Error Spot   (Site not responding. Last check: 2007-11-02)
In digital telecommunications, channel coding is a pre-transmission mapping applied to a digital signal or data file, usually with an error-detection or an error-correction code.
Information theory tells us that whatever be the probability of error in transmission or storage, it is possible to construct error-correcting codes in which the likelihood of failure is arbitrarily low, although this requires adding increasing amounts of redundant data to the original, which might not be practical when the error probability is very high.
Other block error-correcting codes, such as Reed-Solomon codes transform a chunk of bits into a (longer) chunk of bits in such a way that errors up to some threshold in each block can be detected and corrected.
www.errorspot.com   (6356 words)

  
 MIMO System Prototyping
Alamouti : Alamouti coding scheme is a simple space-time code, that offers a transmit diversity of 2.
The VIs available encode and decode using Alamouti scheme for any number of receive antennas.
Trellis Codes : The VIs implement a class of space-time trellis codes that are decoded using Viterbi soft decoding.
www.ece.utexas.edu /~rheath/research/mimo/labview/?D=A   (654 words)

  
 Analytical modeling of ad hoc networks that utilize space-time coding
This paper presents the first analytical model for ad hoc networks equipped with multiple-input multiple-output (MIMO) radios using space-time coding (STC) that considers the impact of the underlying radio-based topology on network performance.
The impact of the Alamouti scheme on IEEE 802.11 ad hoc networks is studied by introducing a new analytical model for the IEEE 802.11 DCF MAC.
We apply the Alamouti scheme to different antenna system configurations and compare their performance with respect to the basic s ingle-input-single-output (SISO) IEEE 802.11 DCF MAC.
www.parc.com /research/publications/details.php?id=5956   (234 words)

  
 Alamouti and Space-Time Coding Comparison (via CobWeb/3.1 planetlab-6.cs.princeton.edu)   (Site not responding. Last check: 2007-11-02)
A space-time signaling scheme was introduced by Alamouti in [1].
Space-time coding was introduced by Tarokh, Seshadri, and Calderbank in [3].
Analytical derivations for the Alamouti formulations follow in the report, while the same for the STC case are sited from [3].
portfolio.washington.edu.cob-web.org:8888 /toliy/alamouti-stc   (78 words)

  
 Amazon.com: "linear dispersion codes": Key Phrase page   (Site not responding. Last check: 2007-11-02)
A uni- fied description is provided by the linear dispersion codes addressed in Section 6.4.
One example is linear dispersion codes [HH] that use the sphere decoder and carry a price in signal constellation expansion (as in channel trellis coding, section...
In principle, all of the above are instances of non-orthogonal space-time block codes.
www.amazon.com /phrase/linear-dispersion-codes   (531 words)

  
 Tutorial Overview Tutorial Overview http://www   (Site not responding. Last check: 2007-11-02)
Tarokh, N. Seshadri and A.R. Calderbank, "Space-Time Codes for High Data Rates Wireless Communications: Performance Criterion and Code Construction", IEEE Transactions on Information Theory, Vol 44, Number 2, pp.
Tarokh, H. Jafarkhani, A.R. Calderbank, " Space-Time Block Coding for Wireless Communications: Performance Results", IEEE Journal on Select Areas in Communications, Vol.17, No. 3, March 1999.
Sandhu, A. Paulraj, " Space-Time Block Codes versus Space-Time Trellis Codes," Proceedings of the ICC, pp.
users.isr.ist.utl.pt /~frikel/spacetime.html   (119 words)

  
 Course #39, Digital Mobile and Wireless Communications:  The Radio Interface for 2G, 3G, and Beyond
One important element of these systems is the radio interface, or physical layer, which includes the modulation, coding, equalization, diversity, and multiple access techniques.
Turbo codes and LDPC codes approach the famous Shannon limits on communications.
The Alamouti space-time technique and multi-user techniques are becoming a standard in many wireless systems.
www.cei.se /039.htm   (495 words)

  
 RE: stds-80220-requirements: Antenna Diversity Requirement, 4.1.1 2
Joseph, while a 2x2 antenna configuration with Alamouti coding may be a good design point, we would want to avoid that type of specification unless it could be reasonably shown that this was the only antenna configuration that could lead to a useful solution set.
Generally, we must all be on our guard to specify requirements that are as independent of implementations as possible.
An example is 2x2 antenna configuration with Alamouti coding.
www.ieee802.org /20/email_req/msg00244.html   (546 words)

  
 Combining Orthogonal Space-Frequency Block Coding and Spatial Multiplexing in MIMO-OFDM System - Rahman, Marchetti ...   (Site not responding. Last check: 2007-11-02)
Abstract: In the present work, we have combined Orthogonal Space-Frequency Block Coding (OSFBC) and Spatial Multiplexing (SM) in one transmission scheme for Orthogonal Frequency Division Multiplexing (OFDM) systems.
In the combined transmission scheme, both spatial diversity and multiplexing benefits are possible to achieve.
Simple Alamouti coding as the S-F coding across spatial multiplexing branches and a simplified linear receiver instead of a complex successive interference cancellation receiver are...
citeseer.ist.psu.edu /rahman05combining.html   (326 words)

  
 Dr. Dobb's | Designing Multi-antenna Signal Processing for Mobile WiMax | September 21, 2006
The first is Matrix A, which is a space-time or Alamouti coding scheme that delivers more robust links through diversity.
The second is Matrix B, which is a spatial multiplexing scheme used to increase subscriber data rates.
The last thing that system designers should have to do is devote resources to writing a lot of assembly code to perform those types of tasks.
www.ddj.com /dept/global/193004406?pgno=2   (878 words)

  
 ACE / NEWCOM Autumn School - Space Time Block Coding (STBC) - October 2006   (Site not responding. Last check: 2007-11-02)
The purpose of this school is to provide the standard and new tools of the space-time coding used in wireless communications.
We will focus on the well-known block coding (Alamouti and BLAST schemes) as well as on the most recent and powerful coding such as Golden codes.
In order to submit a talk (which has to rely on space-time coding), just send an email to Philippe Ciblat (before 09/22)
www.comelec.enst.fr /~ciblat/stbc_school   (389 words)

  
 Course #58, Modern Digital Modulation Techniques for Wireless, Satellite, and Wireline Communications
Relatively new concepts, such as OFDM and OFDMA, MIMO and BLAST, and adaptive modulation and coding methods are becoming more and more important in the implementation of modern systems.
New techniques, including OFDM-MIMO, space-time coding, iterative techniques, and adaptive modulation and coding, which greatly improve the bandwidth and power efficiency of communication, will also be discussed, as well as the information theory limits on communications.
A topic of increasing importance is the turbo-coding (iterative decoding) concept and its use in areas such as antenna diversity, equalization and OFDM.
www.cei.se /058.htm   (573 words)

  
 Amazon.com: "Sphere Decoder": Key Phrase page   (Site not responding. Last check: 2007-11-02)
Algebraic Number Theory And Code Design For Rayleigh Fading Channels (Foundations and Trends in Communications and Information The) by Frederique Oggier, Emanuele Viterbo
of Alamouti coding, can realize higher rates at modest complexity.
One example is linear dispersion codes [HH] that use the sphere decoder and carry a price in signal constellation expansion (as in channel trellis coding, section 3.6.4).
www.amazon.com /phrase/Sphere-Decoder   (550 words)

  
 ArrayComm -- Improving wireless economics through MAS software    
SDMA — Spatial division multiple access utilizes AAS to enable spatial multiplexing of any given subchannel to/from more than one client device at the same time.
Matrix A — In the WiMAX environment, space-time coding (STC, also known as Alamouti coding) is known as Matrix A MIMO.
This technology captures diversity gains by sending a single data stream in two parts out of two antennas, interleaved with transformed versions of the same information, so that the receiver has higher probability of extracting the desired signal successfully.
www.arraycomm.com /serve.php?page=principles   (1496 words)

  
 BAI Course 077: CDMA and OFDM: The Radio Interface
• Elaborate on the basic building blocks of cellular systems: modulation, coding, equalization, diversity.
Engineers interested in the physical interface of current and future CDMA and OFDM systems will benefit from this introductory course.
• Block coding (Reed Solomon code) • Interleaving • Viterbi algorithm • Trellis coding • Convolutional coding • Concatenated coding • Turbo-coding • Performance over Rayleigh fading channels • Information theory bounds for fading channels • Space-Time coding
www.bessercourse.com /outlinesOnly.asp?CTID=77   (457 words)

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