3G MIMO
Encyclopedia
3G MIMO describes MIMO
MIMO
In radio, multiple-input and multiple-output, or MIMO , is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology...

 techniques which have been considered as 3G
3G
3G or 3rd generation mobile telecommunications is a generation of standards for mobile phones and mobile telecommunication services fulfilling the International Mobile Telecommunications-2000 specifications by the International Telecommunication Union...

 standard techniques.

MIMO
MIMO
In radio, multiple-input and multiple-output, or MIMO , is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology...

, as the state of the art of Intelligent antenna (IA), improves the performance of radio systems by embedding electronics intelligence
Intelligence
Intelligence has been defined in different ways, including the abilities for abstract thought, understanding, communication, reasoning, learning, planning, emotional intelligence and problem solving....

 into the spatial processing unit. Spatial processing includes spatial precoding at the transmitter and spatial postcoding at the receiver, which are dual each other from information signal processing theoretic point of view. Intelligent antenna is technology which represents smart antenna
Smart antenna
Smart antennas are antenna arrays with smart signal processing algorithms used to identify spatial signal signature such as the direction of arrival of the signal, and use it to calculate beamforming vectors, to track and locate the antenna beam on the mobile/target...

, multiple antenna (MIMO), self-tracking directional antenna, cooperative virtual antenna and so on.

Technology

Spatial precoding of intelligent antenna includes spatial beamforming and spatial coding. In wireless communications, spatial precoding has been developing for high reliability, high rate and lower interference as shown in the following table.

Summary of 3G MIMO

The table summarizes the history of 3G MIMO techniques candidated for 3G standards. Although the table additionally contains the future part but the contents are not clearly filled out since the future is not precisely predictable.
Generation 3G 3G evolution Beyond 3G Future
Deployment 2003/4 2005~6/2007~8/2009~10 2012~2015 2015~2020
Standard WCDMA HSPA/HSPA+/LTE IMT-Advanced Beyond IMT-Adv
Total rate 384kbit/s 14/42/65~250Mbit/s 1Gbit/s >10Gbit/s
Bandwidth 5 MHz 5 MHz/20 MHz 20~100 MHz >100 MHz
Requirement Paradigm High reliability (High quality) High rate (High capacity) Lower interference High intelligence
Method Spatial diversity Spatial multiplexing Spatial cancellation Ambient intelligence
Spatial coding (SC) Spatial diversity coding Spatial multiplexing coding Spatial cancellation coding Ambient intelligence coding
Spatial beamforming (SB) Single-stream beamforming Multi-stream beamforming Interference nulling beamforming Ambient intelligence beamforming
Examples SC: Alamouti coding, SB: TxAA SC: BLAST coding, SB: SVD SC: DPC, SB: MU-BF Such as cooperative MIMO

IA in ad-hoc networking

IA technology enables client terminals which have either multiple antennas or self-tracking directional antenna to communicate each other with as high signal-to-interference-and-noise ratio (SINR) as possible. Assume that there are a source terminal, a destination terminal and some candidate interference terminals. Differently from conventional approaches, an advanced IA based terminal will perform spatial precoding (spatial beamforming and/or spatial coding) not only to enhance the signal power at the destination terminal but also to diminish the interferening power at interference terminals. As a human does, the advanced IA terminal is given to know that occurring high interference to other terminals will eventually degrade the performance of the associated wireless network.

Intelligent antenna (IA) vs. Cognitive radio (CR)

However, it requires intelligent multiple or cooperative
Cooperation
Cooperation or co-operation is the process of working or acting together. In its simplest form it involves things working in harmony, side by side, while in its more complicated forms, it can involve something as complex as the inner workings of a human being or even the social patterns of a...

 antenna array. On the contrary, cognitive radio
Cognitive radio
A cognitive radio is a kind of two-way radio that automatically changes its transmission or reception parameters, in a way where the entire wireless communication network -- of which it is a node -- communicates efficiently, while avoiding interference with licensed or licensed exempt users...

 (CR) allows user terminals to sense the other service usage of spectrum beans to share the spectrum among users, which is so, cognitive spectrum sharing technology. The following table compares the different points between two approach for future wireless systems: Intelligent antenna (IA) vs. Cognitive radio (CR).
Point Intelligence antenna (IA) Cognitive radio (CR)
Interference processing Cancellation by spatial pre/post-coding Avoidance by spectrum sensing
Key cost Multiple or cooperative antenna arrays Spectrum sensing and multi-band RF
Solution Intelligent spatial beamforming/coding tech Cognitive spectrum management tech
Application Ambient Spatial Reuse Open Spectrum Sharing
Applied theory Dirty paper and Wyner-Ziv coding (DP-WZ coding) Software radio and cognition
Summary Intelligent spectrum reuse technology Cognitive spectrum sharing technology

Fundamental concepts and theories

  • Intelligence
    Intelligence
    Intelligence has been defined in different ways, including the abilities for abstract thought, understanding, communication, reasoning, learning, planning, emotional intelligence and problem solving....

    is a property of mind that includes many related abilities.
  • Cooperation
    Cooperation
    Cooperation or co-operation is the process of working or acting together. In its simplest form it involves things working in harmony, side by side, while in its more complicated forms, it can involve something as complex as the inner workings of a human being or even the social patterns of a...

    is the practice of social elements working in common, instead of working individually.
  • Cognition
    Cognition
    In science, cognition refers to mental processes. These processes include attention, remembering, producing and understanding language, solving problems, and making decisions. Cognition is studied in various disciplines such as psychology, philosophy, linguistics, and computer science...

    can be interpreted as understanding and responding to the world.
  • Ambient intelligence
    Ambient intelligence
    In computing, ambient intelligence refers to electronic environments that are sensitive and responsive to the presence of people. Ambient intelligence is a vision on the future of consumer electronics, telecommunications and computing that was originally developed in the late 1990s for the time...

     (AmI)
    refers to artificial environments that responses to the movement of people, the paradigm of which builds upon Ubiquitous computing
    Ubiquitous computing
    Ubiquitous computing is a post-desktop model of human-computer interaction in which information processing has been thoroughly integrated into everyday objects and activities. In the course of ordinary activities, someone "using" ubiquitous computing engages many computational devices and systems...

    .
  • Wireless ubiquitous computing
    Ubiquitous computing
    Ubiquitous computing is a post-desktop model of human-computer interaction in which information processing has been thoroughly integrated into everyday objects and activities. In the course of ordinary activities, someone "using" ubiquitous computing engages many computational devices and systems...

     (WUC)
    is post-desktop computing where information processing is integrated into anytime and anywhere human activities.
  • Game theory
    Game theory
    Game theory is a mathematical method for analyzing calculated circumstances, such as in games, where a person’s success is based upon the choices of others...

    is a mathematical theory that studies the strategic interaction between players, which are usually organized into a friend group and an enemy group.

Principal Issues of Research

The following items list the issues of the multiple antenna research aims to improve the performance of radio communications.
  • Intelligent antenna
  • Smart antenna
    Smart antenna
    Smart antennas are antenna arrays with smart signal processing algorithms used to identify spatial signal signature such as the direction of arrival of the signal, and use it to calculate beamforming vectors, to track and locate the antenna beam on the mobile/target...

  • Multiple-input multiple-output (MIMO)
  • Beamforming
    Beamforming
    Beamforming is a signal processing technique used in sensor arrays for directional signal transmission or reception. This is achieved by combining elements in the array in a way where signals at particular angles experience constructive interference and while others experience destructive...

  • Diversity combining
    Diversity combining
    Diversity combining is the technique applied to combine the multiple received signals of a diversity reception device into a single improved signal.- Various techniques :Various diversity combining techniques can be distinguished:...

  • Diversity scheme
    Diversity scheme
    In telecommunications, a diversity scheme refers to a method for improving the reliability of a message signal by using two or more communication channels with different characteristics. Diversity plays an important role in combatting fading and co-channel interference and avoiding error bursts...

  • Space–time code
    Space–time code
    A space–time code is a method employed to improve the reliability of data transmission in wireless communication systems using multiple transmit antennas...

  • Spatial multiplexing
    Spatial multiplexing
    Spatial multiplexing is a transmission technique in MIMO wireless communication to transmit independent and separately encoded data signals, so-called streams, from each of the multiple transmit antennas...

  • Space-division multiple access (SDMA)
    Space-division multiple access
    Space-Division Multiple Access is a channel access method based on creating parallel spatial pipes next to higher capacity pipes through spatial multiplexing and/or diversity, by which it is able to offer superior performance in radio multiple access communication systems...

  • Advanced MIMO communications
  • Multi-user MIMO
    Multi-user MIMO
    In radio, multi-user MIMO is a set of advanced MIMO, multiple-input and multiple-output , technologies that exploit the availability of multiple independent radio terminals in order to enhance the communication capabilities of each individual terminal...

  • Precoding
    Precoding
    Precoding is a generalization of beamforming to support multi-layer transmission in multi-antenna wireless communications. In conventional single-layer beamforming, the same signal is emitted from each of the transmit antennas with appropriate weighting such that the signal power is maximized at...

  • Dirty paper coding (DPC)
  • Cooperative wireless communications
  • Cooperative diversity
    Cooperative diversity
    Cooperative diversity is a cooperative multiple antenna technique for improving or maximising total network channel capacities for any given set of bandwidths which exploits user diversity by decoding the combined signal of the relayed signal and the direct signal in wireless multihop networks...


Definitions

Here are the definition of principal keywords to clarify the objective and the operations of intelligent antenna.
Terminology Definition
Intelligent antenna Antenna technology that uses some sort of electronic intelligence to enhance wireless system performance. Electronic intelligence is implemented by spatial pre/post-coding techniques such as spatial information coding and spatial signal beamforming. Notice that smart antenna has been more widely used to represent the similar meaning.
Smart antenna
Smart antenna
Smart antennas are antenna arrays with smart signal processing algorithms used to identify spatial signal signature such as the direction of arrival of the signal, and use it to calculate beamforming vectors, to track and locate the antenna beam on the mobile/target...

In the narrow sense, antenna technology that employs array antennas with beamforming techniques to enhance wireless system performance. In the wide sense, equivalent terminology to intelligent antenna.
MIMO
MIMO
In radio, multiple-input and multiple-output, or MIMO , is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology...

Wide sense and well-known: MIMO is the state of the art of IA and SA.
  • Narrow sense: Antenna systems that employ multiple antennas at both the transmitter and the receiver.

Reference Web Sites

The following items list the web sites related to the multiple antenna research.
  • MARS, Bell Laboratories — http://mars.bell-labs.com/
    • Multiple Antenna Research and Solutions (MARS) is a research group on multiple antenna and space time coding

  • Lucent — http://www.cdg.org/news/events/CDMASeminar/cdg_tech_forum_02/3_lucent_ia_blast_final_release.pdf
    • The goal of intelligent antennas is to achieve higher capacity noting that advanced solutions provide higher capacity than basic solutions.
      Types Antenna configuration Basic solution Advanced solution
      Diversity d > wavelength Rx: MRC , MMSE, etc, Tx: STTD, CLTD BLAST (spatial multiplexing)
      Phased Array d < wavelength Switched beams Steered beams

  • IMEC — http://www.imec.be/wireless/mimo/
    • Multiple antenna systems are the key to the high-capacity wireless universe. Indeed, they allow increasing the rate, improving the robustness, or accommodating more users in the cell.

  • Georgia Institute of Technology — http://users.ece.gatech.edu/~mai/tutorial_sa_def.htm
    • A smart antenna is an array of antenna elements connected to a digital signal processor

  • IEC — http://www.iec.org/online/tutorials/smart_ant/index.html, http://www.iec.org/online/tutorials/acrobat/smart_ant.pdf
    • A smart antenna system combines multiple antenna elements with a signal-processing capability to optimize its radiation and/or reception pattern automatically in response to the signal environment.
    • Spatial division multiple access (SDMA) — Among the most sophisticated utilizations of smart antenna technology is SDMA, which employs advanced processing techniques to, in effect, locate and track fixed or mobile terminals, adaptively steering transmission signals toward users and away from interferers.

  • SearchMobileComputing.com — http://searchmobilecomputing.techtarget.com/sDefinition/0,290660,sid40_gci1026138,00.html
    • A smart antenna is a digital wireless communications antenna system that takes advantage of diversity effect at the source (transmitter), the destination (receiver), or both.
    • MIMO is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver).

  • Smart Antennas Research Group, Stanford Univ. — http://www.stanford.edu/group/sarg/
    • Our research goal is to advance the state-of-the-art in the applications of multiple antennas and space-time signal processing in mobile wireless networks, and to improve network performance and economics.

  • CDG — http://www.cdg.org/technology/cdma_technology/smart_antennas/index.asp, http://www.cdmatech.com/products/how_mimo_works.jsp
    • Smart antennas provide greater capacity and performance benefits than standard antennas because they can be used to customize and fine-tune antenna coverage patterns that match the traffic conditions in a wireless network or that are better suited for complex radio frequency (RF) environments.
    • MIMO employs multiple, spatially separated antennas (at both TX and RX) to take advantage of these "virtual wires" and transfer more data.

  • Nortel — http://www2.nortel.com/go/solution_content.jsp?segId=0&catId=0&parId=0&prod_id=61701
    • MIMO is an antenna technology that is used both in transmission and receiver equipment for wireless radio communication.
    • MIMO is the only advanced antenna technology that simultaneously offers high bandwidth, improved range, and high mobility at a lower cost.

  • Visant Strategies — http://www.visantstrategies.com/market_research/mimo_intelligent_antenna.html, http://www.researchandmarkets.com/reports/c21454
    • Intelligent antennas are antenna systems that use some sort of computational or electronic resource to enhance system performance.
    • According to the amounts of intelligence employed, antenna diversity represents the simplest form in the progressive complexity chain, followed by basic beamforming, which is the process of narrowing radiated energy, which is then followed by the more complex space-time processing and finally by MIMO.

  • VK5ZAI — http://www.electric-web.org/tracking_antenna.htm
    • Following numerous requests for details of my home brewed satellite tracking system I have finally got around to writing an article on it, with a photograph or two, hoping it's of interest to others.

  • Magnetic Sciences — http://www.magneticsciences.com/SatelliteTrackingUnits.html
    • Satellite tracking systems and self-steering antennas are used aboard ships, vehicles, or aircraft to maintain contact with satellites.

See also

  • http://www.wireless-world-research.org/fileadmin/sites/default/files/about_the_forum/WG/WG4/Briefings/WWRF-WG4_SmartAntennas_briefing.pdf

Intelligent antenna series

  • Diversity antenna
    Antenna diversity
    Antenna diversity, also known as space diversity, is any one of several wireless diversity schemes that uses two or more antennas to improve the quality and reliability of a wireless link. Often, especially in urban and indoor environments, there is no clear line-of-sight between transmitter and...

  • Smart antenna
    Smart antenna
    Smart antennas are antenna arrays with smart signal processing algorithms used to identify spatial signal signature such as the direction of arrival of the signal, and use it to calculate beamforming vectors, to track and locate the antenna beam on the mobile/target...

  • Multiple antenna
  • MIMO antenna
  • Cooperative antenna

Practical Implementation Techniques

  • Spatial pre/post-coding
    Precoding
    Precoding is a generalization of beamforming to support multi-layer transmission in multi-antenna wireless communications. In conventional single-layer beamforming, the same signal is emitted from each of the transmit antennas with appropriate weighting such that the signal power is maximized at...

     includes spatial coding (SC) and spatial beamforming (SB).
    • Spatial coding (SC)
      Space–time code
      A space–time code is a method employed to improve the reliability of data transmission in wireless communication systems using multiple transmit antennas...

       includes single layer SC
      Space–time code
      A space–time code is a method employed to improve the reliability of data transmission in wireless communication systems using multiple transmit antennas...

      , multi-layer SC
      Spatial multiplexing
      Spatial multiplexing is a transmission technique in MIMO wireless communication to transmit independent and separately encoded data signals, so-called streams, from each of the multiple transmit antennas...

       and multi-user SC.
    • Spatial beamforming (SB)
      Beamforming
      Beamforming is a signal processing technique used in sensor arrays for directional signal transmission or reception. This is achieved by combining elements in the array in a way where signals at particular angles experience constructive interference and while others experience destructive...

       is antenna processing which generates an artificially shpaed beam with respect to azimuth, ellibation, width, length and distribution of a beam.
  • Wideband Space Division Multiple Access
    Wsdma
    WSDMA is a high bandwidth channel access method, developed for multi-transceiver systems such as active array antennas. WSDMA is a beamforming technique suitable for overlay on the latest air-interface protocols including WCDMA and OFDM...

     is a technique that employs a Smart antenna
    Smart antenna
    Smart antennas are antenna arrays with smart signal processing algorithms used to identify spatial signal signature such as the direction of arrival of the signal, and use it to calculate beamforming vectors, to track and locate the antenna beam on the mobile/target...

    for 3G MIMO benefits.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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