Preview

Mimo

Good Essays
Open Document
Open Document
544 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Mimo
MIMO IN WIRELESS COMMUNICATION

Wireless communication refers to the transfer of information between two or more points that are not physically connected. Distances between the two points can be short or as far as thousands or even millions of kilometers. Different ways can be used to establish wireless communication. Basically, antennas are used as transmitter and receiver in wireless communications like cellular telephones, satellite communications, radio broadcasting, etc. Despite many advantages of wireless communication there are many factors that affect the quality of wireless communication systems.
In urban and indoor environments, there are many obstacles between the clear line-of-sight (LOS) between transmitter and receiver. Instead the signal is reflected along multiple paths before finally being received. Each of these bounces can introduce phase shifts, time delays, attenuations, and distortions at the receivers. These destructively and constructively interfere with one another at receiving antenna degrading the quality of signal sent. Many researches have been done to mitigate this problem. One of the most prominent ways is to use MIMO techniques.
MIMO (Multiple Input and Multiple Output) is a technique in which multiple antennas are used both at the receiver and the transmitter for better communication performance.
In 1996, Greg Raleigh and Gerard J. Foschini refined new approaches to MIMO technology, considering a configuration where multiple transmit antennas are co-located at one transmitter to improve the link throughput effectively.
It is been said that MIMO offers significant increase in data throughput and quality without additional bandwidth or increased transmit power. It achieves this goal by spreading the same total transmit power over the antennas to achieve an array gain that improves the spectral efficiency (more bits per second per hertz of bandwidth) or to achieve a diversity gain that improves the link reliability. It

You May Also Find These Documents Helpful

  • Good Essays

    Interference in wireless networks results from multiple users sharing time and frequency resources scheme. Interference may be mitigated in MIMO systems by exploiting the spatial dimension to increase the separation among users. Interference reduction and avoidance improve the coverage and range of a wireless network.…

    • 674 Words
    • 3 Pages
    Good Essays
  • Good Essays

    It 242 Week 8 Assignment

    • 686 Words
    • 3 Pages

    Microwave signals, Infrared Systems, Satellite Signals, and radio systems all have made strides in improving the signal speed and quality. Wireless signals have pros and cons that influence their commercial use and present day application. However, no matter the progress made with wireless signal frequencies they are always subject to interference from technologies limiting their effeteness.…

    • 686 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Week 8 It-242

    • 685 Words
    • 3 Pages

    For a while in the past, we refer the wireless technology as cellular phones. But now, the term "wireless" refers to more varied devices & technologies, like smartphones, computers, printers, headphones and even speakers that connects together in different ways. Today’s wireless phones for example, may include data packets like 3G & 4G cellular radio signals, Wi-Fi and even Bluetooth technologies, these technologies have advance in a fast pace that investing in equipment like 4G phone and/or 802.11x wireless routers can offer you & your business a variety of speed improvements for your money. Now I shall describe the characteristics of every type of wireless signal types so we can learn to use every signal type.…

    • 685 Words
    • 3 Pages
    Good Essays
  • Powerful Essays

    Study Guide

    • 1194 Words
    • 5 Pages

    MIMO is a space-division multiplexing technique where data stream is split into multiple parts called spatial streams. In 802.11n in doubling the spatial stream doubles the effective data…

    • 1194 Words
    • 5 Pages
    Powerful Essays
  • Good Essays

    The technology in which the parameters such as amplitude, phase and frequency of radio frequency waves are changed so as to transmit and receive the information is known as RF technology or radio frequency technology. In this, the electromagnetic waves that lie in the range of 3 khz to 300 Ghz are used for the wireless communication between the two devices. The signal is modulated at the transmitter end and then the antenna converts this electrical signal into the radio waves and emits them. The medium in which they travel is space. The receiving antenna catches the waves at the receiving end and then the signal is demodulated and converted back to its original form. These waves are highly affected by the interference…

    • 648 Words
    • 3 Pages
    Good Essays
  • Good Essays

    The first type of wireless radio wave transmission to describe in this paper is 802.11B. The 802.11B was an amendment to the original 802.11 standard released in because the original did not have fast enough speeds to be sufficient to support the needs that the technology required. 802.11B added speeds of 5.5 and 11 Mbps. The 802.11B standard also supports wireless devices that are up…

    • 764 Words
    • 4 Pages
    Good Essays
  • Satisfactory Essays

    Wireless Signals

    • 551 Words
    • 3 Pages

    Wireless signals are all around us as we walk or drive around the city or town where we live. The four types of wireless technologies that are out there are Wi-Fi, Cellular, Bluetooth, and WiMAX. We will be looking at these types of wireless technologies a little more in depth, where are they most commonly used, and how they differ from one another. The first wireless technology that we will be looking at is the Wi-Fi wireless signal. The Wi-Fi signal is mainly associated with computer networking, the specification used to create a wireless local area network is the IEEE 802.11. One would use this type of wireless technology if you were a business owner opening up a coffee shop and needed a public network. The network would have a wired connection to an internet source, then leading to a wireless router that transmits and receives the data from all of the customer’s devices that want to use the Wi-Fi. This will also connect all of the devices to one another through the network. The next type of wireless technology that we will be looking at is Cellular. This type of wireless technology is most often associated with wireless telephones. The cellular network is connected to cells that will enable a user to move around freely while staying connected to the network. This type of signal is used everywhere you go nowadays and are used by everyone. There are a multitude of devices that use these networks at one time and those include, smart phones, tablets, and some computers can use the cell towers to get a signal to be able to use the internet. The first generation of cellular signals was completely analog, and from there with the growing demand of faster speeds and better connectivity technology brought us 2G, 3G, and the ever popular 4G phones. Bluetooth is the next technology that we will touch on and is very similar to the Wi-Fi and cellular networks but on…

    • 551 Words
    • 3 Pages
    Satisfactory Essays
  • Good Essays

    There are lots of different kinds of wireless technologies on the market in today’s technology world. The four kinds of cordless technologies I would prefer to speak about will be IR or Infrared, satellite signals, microwave signals, as well as radio systems. These kinds of systems transmit data in various ways and strengths. All of these types of systems have their advantages and disadvantages. Infrared is dependent on the utilization of infrared light signals. Infrared light isn't noticeable by the human eye. This kind of signal utilized LEDs and ILDs to transmit signals as well as photodiodes to receive signals. The frequencies which IR can operate are from 100 GHz to 1000 THz. The drawback is that it can't pass through physical objects for example walls and other hurdles.…

    • 514 Words
    • 2 Pages
    Good Essays
  • Satisfactory Essays

    Mobile And Wireless

    • 455 Words
    • 1 Page

    The foundation of any network is some sort of pathway for digital data (bits) to move back and forth between connected agents. Cables, ranging from coaxial to optical, have long dominated this realm. However, wireless is increasingly emerging as a viable alternative to direct physical connection (Stanford University, 2003). Wireless includes many various mediums such as AM, FM, HD and SiriusXM radio. Broadcast and satellite TV, and most, if not all, internet access and cellphones, are now wireless.…

    • 455 Words
    • 1 Page
    Satisfactory Essays
  • Powerful Essays

    This full text paper was peer reviewed at the direction of IEEE Communications Society subject matter experts for publication in the IEEE ICC 2009 proceedings…

    • 4413 Words
    • 18 Pages
    Powerful Essays
  • Powerful Essays

    (·)−1 is reserved for the matrix inverse and (·)H for Hermitian transposition. The estimated value of a variable a is…

    • 2012 Words
    • 9 Pages
    Powerful Essays
  • Good Essays

    – - Beamforming: spatial focusing of correlated signals – - Rx/Tx diversity: combining of decorrelated signals – - MIMO: increasing spectral efficiency/ data rates…

    • 1099 Words
    • 5 Pages
    Good Essays
  • Good Essays

    Transmit Diversity

    • 7383 Words
    • 30 Pages

    So far we have investigated the use of antenna arrays in interference cancellation and for receive diversity. This final chapter takes a broad view of the use of antenna arrays in wireless communications. In particular, we will investigate the capacity of systems using multiple transmit and/or multiple receive antennas. This provides a fundamental limit on the data throughput in multipleinput multiple-output (MIMO) systems. We will also develop the use of transmit diversity, i.e., the use of multiple transmit antennas to achieve reliability (just as earlier we used multiple receive antennas to achieve reliability via receive diversity). The basis for receive diversity is that each element in the receive array receives an independent copy of the same signal. The probability that all signals are in deep fade simultaneously is then significantly reduced. In modelling a wireless communication system one can imagine that this capability would be very useful on transmit as well. This is especially true because, at least in the near term, the growth in wireless communications will be asymmetric internet traffic. A lot more data would be flowing from the base station to the mobile device that is, say, asking for a webpage, but is receiving all the multimedia in that webpage. Due to space considerations, it is more likely that the base station antenna comprises multiple elements while the mobile device has only one or two. In addition to providing diversity, intuitively having multiple transmit/receive antennas should allow us to transmit data faster, i.e., increase data throughput. The information theoretic analysis in this chapter will formalize this notion. We will also introduce a multiplexing scheme, transmitting multiple data streams to a single user with multiple transmit and receive antennas. This chapter is organized as follows. Section 2 then presents a theoretical analysis of the capacity of MIMO systems. The…

    • 7383 Words
    • 30 Pages
    Good Essays
  • Powerful Essays

    tag to tag communication

    • 5352 Words
    • 22 Pages

    section”, IEEE Antennas and Propagation Society International Symposium, Jul. 1997, vol. 2, pp. 1172 - 1175…

    • 5352 Words
    • 22 Pages
    Powerful Essays
  • Powerful Essays

    Wifi Technology

    • 1609 Words
    • 7 Pages

    Wi-Fi allows to connect to the internet from virtually anywhere at speeds of up to 54Mbps.The computers and handsets enabled with this technology use radio technologies based on the IEEE 802.11 standard to send and receive data anywhere within the range of a base station.…

    • 1609 Words
    • 7 Pages
    Powerful Essays