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Wavion Beamforming technology uses antenna array signals to focus the energy to and from the user. Beamforming is done by multiplying the signal at each antenna by a set of complex (phase and amplitude) weights. In transmit, the beamforming weights are set so that the signals from the different antennas sum up coherently at the receiving client. www.wavionnetworks.com /tech/beamforming.html   (343 words)

Beamforming Beamforming is a general signal processing technique used to control the directionality of the reception or transmission of a signal on a transducer array. Using beamforming you can direct the majority of signal energy you transmit from a group of transducers (like audio speakers or radio antennae) in a chosen angular direction. The basic point in beamforming is, when you set multiple transducers next to each other sending out signals, you're going to get some kind of interference pattern, just like you see in a pond when you throw several stones in at once and create interfering ripples. staff.washington.edu /aganse/beamforming/beamforming.html   (1606 words)

Beamforming - Wikipedia, the free encyclopedia As the name indicates, an adaptive beamformer is able to automatically adapt its response to different situations. Beamforming is a term that has been frequently used in the discussion of sensor networks. A conventional beamformer is a simple beamformer also known as delay-and-sum beamformer. en.wikipedia.org /wiki/Beamforming   (638 words)

Delay and Sum Beamforming with a 2D Array: Introduction Beamforming is the discipline that takes a set of microphones, usually in an array, and a set of point source signals (in a space that we assumed to be R3 or very nearly so) and tries to focus on one signal source to the exclusion of both noise and other signal sources. In this project, we assume a single source and use the old and powerful technique of delay and sum beamforming implemented over a 2-dimensional array arranged as a 3 by 3 square with the center missing. Delay and sum beamforming is quite true to its name as it merely takes the set of signals, delays and maybe weights them by varying amounts, and then adds them all together. cnx.org /content/m13161/latest   (1105 words)

MPRG - Research Thrust Areas The objective of beamforming is to separate the desired signal from interfering signals given that all the signals share the same frequency band but have unique spatial signatures associated with them. The frequency domain beamformer’s task is to minimize the effect of the multiplicative distortion induced by fading channels. Therefore, equalization is not performed, and the multiplicative factor is passed to the beamformer which steers the antenna array towards the desired direction. www.mprg.org /research/OFDM/ofdm_beamforming.html   (635 words)

Wavion Beamforming improves significantly the link gain thus increasing range and rate, makes coverage more uniform thus eliminating dead spots, and reduces susceptibility to interference thus increasing the signal quality. The improvement in range and rate resulting from the beamforming gain are presented in Figure 1, where Wavion's beamforming performance is compared to a conventional access point in typical non-line-of-sight propagation model. The improved performance stems from the fact that the fades in the different antennas occur in different frequency bins and that the beamformer, by properly weighting the different frequency bins in the different antennas, is able to effectively mitigate the fades. www.wavionnetworks.com /tech/index.html   (892 words)

T-Phase Project at NOAA/PMEL/OERD Beamforming is a signal processing method to focus a stationary array of signal receivers, e.g. The theoretical analysis of beamforming is very complex and highly mathematical, see references below, and will not be shown in this document. The beamformer program allows users to predefine which arrays of hydrophones will be used to focus the beams at the directions of interest that signals will be coming. www.pmel.noaa.gov /vents/staff/lau/tphase/beamforming.html   (656 words)

Adaptive beamforming and Noise cancellation For achieving such a system, adaptive beamforming and noise cancellation techniques will be used using normalized LMS algorithm. The processed output of the beamformer and adaptive noise canceller will be used as an input to an HMM to check for the recognition accuracy. The main area of research will be to enhance the beamformer performance to achieve even higher accuracy rates under varying noise conditions. www.cnel.ufl.edu /~kkale/6586Project.html   (578 words)

[No title] Beamforming is accomplished by adding the weights data from each of the array elements as indicated in Figure 5. A partial beamformer multiplies the array data by the weights and sums the five channels to form a partial beam. Also key is the development of the QR decomposition FPGA core, which simplifies the calculation of the adapted beam weights and reduces the numerical precision and hence, word lengths required. www.afrlhorizons.com /ETB/ETBriefs/Apr06/5657_400.html   (1499 words)

Beamforming A beamformer is a spatial filter that operates on the output of an array of sensors in order to enhance the amplitude of a coherent wavefront relative to background noise and directional interference. The goal of beamforming is to sum multiple elements to achieve a narrower response in a desired direction (the MRA). The (optional) shading of the sensor outputs is done to improve the spatial response characteristics of the beam, and is roughly equivalent to "windowing" in DSP theory. www.ece.utexas.edu /~allen/Beamforming   (788 words)

[No title]   (Site not responding. Last check: 2007-10-03) Five implementations of time-delay beamforming’s core processing component, the multiply-accumulator, were designed, specified in VHDL, tested for correctness in simulation and implemented with Xilinx CAD tools for the Virtex II Pro VP100 FPGA. 1 Introduction Beamforming is a spatial filtering operation performed on the data received by an array of sensors, such as antennas, microphones or hydrophones. Beamforming not only causes the system to be more sensitive to signals coming from a specific direction, but also attenuates the noise and interference coming from other directions. www.ece.neu.edu /~aconti/aconti_G361_beamforming_final.doc   (944 words)

WiMAX World: Navini mixes beamforming, MIMO Beamforming uses multiple antennas to send a focused beam to an end user, creating a high-capacity link that can be steered throughout the cell area. While both MIMO and beamforming have capacity advantages over standard single antenna systems being certified today, MIMO is often cited as the better technology for dense urban deployments where the signals bouncing off of nearby structure reinforce rather than degrade a connection. Beamforming, meanwhile, is optimal for more stationary or portable applications where the focused beam can be extended far beyond the radius of the typical MIMO base station. telephonyonline.com /wimax/technology/navini_beamforming_mimo_101006   (852 words)

Beamforming Basics Beamforming is the process of trying to concentrate the array to sounds coming from only one particular direction. The delay and sum beamformer is based on the idea that if a ULA is being used, then the output of each sensor will be the same, except that each one will be delayed by a different amount. Delay and sum beamformers are not very commonly used in practical applications, because they do not work to well, but they do explain a tricky concept simply, which is why they are often used to introduce beamforming. cnx.org /content/m12563/latest   (575 words)

Smart Antennas—Beamforming   (Site not responding. Last check: 2007-10-03) In beamforming, each user’s signal is multiplied with complex weights that adjust the magnitude and phase of the signal to and from each antenna. The beamforming unit on each Rake finger then calculates the corresponding beamformer weights and channel estimate using the pilot symbols that have been transmitted through the dedicated physical control channel (DPCCH). There are a number of beamforming architectures and adaptive algorithms that provide good performance under different scenarios such as transmit-receive adaptive beamforming and transmit-receive switched beamforming. www.altera.com /end-markets/wireless/advanced-dsp/beamforming/wir-beamforming.html   (1257 words)

Title page for ETD etd-022099-122645 Beamforming methods are examined which utilize knowledge of the source direction-of-arrival from the MUSIC algorithm. Two methods of phase-steered beamforming are compared in both narrowband and wideband scenarios, and it is shown that phase-steering the array to the desired source direction-of-arrival has about 0.3 dB better beamforming performance than the simple time-delay steered beamformer using no subbands. As the beamforming solution is inadequate to achieve desired results, a generalized sidelobe canceler (GSC) is developed which incorporates a beamformer. scholar.lib.vt.edu /theses/available/etd-022099-122645   (445 words)

Beamforming techniques for acquisition of speech signals   (Site not responding. Last check: 2007-10-03) The approach we take is to use a microphone array in conjunction with a beamforming algorithm to pass the desired speech signal undistorted, while attenuating the undesired interference. Three beamforming algorithms are studied: conventional beamforming, the Frost adaptive beamformer, and the generalized sidelobe canceller (GSC). The conventional beamformer uses fixed weights, while the other two algorithms use weights which adapt to the signal and interference environment. epublish.utdallas.edu /theses/13873   (241 words)

Smart Antennas—Beamforming This method of transmission and reception is called beamforming and is made possible through smart (advanced) signal processing at the baseband. Through adaptive beamforming, the basestation can form narrower beams towards the desired user and nulls towards interfering users, considerably improving the signal-to-interference-plus-noise ratio. The final beamformer weights vector w is related to the R and u outputs of the triangular array as Rw=u. www.openbasestation.org /Newsletters/November2004/Altera_article.htm   (1307 words)

Berliner Beamforming Conference The Berlin Beamforming Conference will be held every year in the second half of November. As is generally known the (passive) beamforming is discussed in acoustic science controversially. Lectures about results of beamforming measurements in practice report the results, not the special (commercial) measurement system. www.acoustic-camera.com /BeBeC/index.html   (449 words)

Acoustic Imaging - Beamforming - Brüel & Kjær The innovative Brüel & Kjær wheel arrays can be used with PULSE Beamforming to produce acoustically optimal results while maintaining maximum ease of use and handling. PULSE Beamforming software is centered around an easy-to-understand tree structure where all measurements and calculations are represented. Beamforming can quickly map both stationary and transient sources. www.bksv.com /PULSELite/4293.asp   (407 words)

Li - Robust Adaptive Beamforming Robust Adaptive Beamforming compiles the theories and work of leading researchers investigating various approaches in one comprehensive volume. Unlike previous efforts, these pioneering studies are based on theories that use an uncertainty set of the array steering vector. Robust wideband beamforming using a steered adaptive beamformer to adapt the weight vector within a generalized sidelobe canceller formulation www.scitechpub.com /li-stoica.htm   (201 words)

[Abstract] Exploiting Spatial Diversity by Low-cost Regular Spatial Sampling (RSS) Beamforming In this communication, the application of a low-cost beamforming concept, which is based on regular spatial sampling (RSS), to wireless communications shall be proposed. This beamforming concept shall be termed RSS beamforming. The authors shall illustrate by simulation results, that RSS beamforming facilitates the exploitation of spatial diversity and outperforms conventional beamforming using spatial matched filtering (SMF). www.actapress.com /Abstract.aspx?paperId=27480   (175 words)

PAPR Reduction for Beamforming OFDM Transmitters This paper presents a new method for PAPR reduction that minimizes the peak power across all antennas while preserving the maximal ratio transmission (MRT) gain and zero-crosstalk criteria at the receivers. Some sys- tems, however, use multiple antennas for frequency-selective transmit beamforming either to a single or multiple simulta- neous receivers. Because the gain and zero crosstalk is preserved at the receivers, no perfor- mance loss is seen by the receivers when using the PAPR- reduced transmit vector. www.priorartdatabase.com /IPCOM/000141448   (574 words)

Active source location and beamforming   (Site not responding. Last check: 2007-10-03) The project aims to build a system that uses audio+video stream information to dynamically locate users and enhance quality of their speech. It implements an efficient dynamic search algorithm capable of both locating and beamforming multiple audio sources distributed in space. The system was presented at "Engineering Acoustics and Signal Processing in Acoustics" conference in May 2000, and was found particularly useful for video conferencing and smart user interfaces. www.umiacs.umd.edu /users/yab/ActvSrcLoc   (87 words)

ECS EPrints Service - Adaptive minimum bit error rate beamforming   (Site not responding. Last check: 2007-10-03) EPrints is free software developed by the University of Southampton to facilitate Open Access to research. An adaptive beamforming technique is proposed based on directly minimizing MBER beamforming is capable of providing significant performance gains in eprints.ecs.soton.ac.uk /10714   (241 words)

[No title] Digital adaptive beamforming (of an array radar) is supposed to make jamming impossible, why do people suggest that Europe develop a dedicated EW aircraft (like Prowler?) to counter the edge that stealth planes have over euro designs? TheArmchairCmd RE:EW aircraft and digital adaptive beamforming 1/10/2006 3:45:39 AM "---How so?" Could it be that PG has read this into some of the suggestions from the Where too now for European military aerospace? 1/12/2006 8:48:07 PM "Digital adaptive beamforming (of an array radar) is supposed to make jamming impossible, " and: " If you can't jam a radar how can a dedicated jammer level the playing field in terms of stealth?" I'm either missing big chunks of comprehension - or this seems to be arse about. www.strategypage.com /militaryforums/6-27884.aspx   (819 words)

Technology - GO Networks   (Site not responding. Last check: 2007-10-03) The GO xRF adaptive beamforming smart antenna engine is the industry’s only smart antenna solution for Metro Wi-Fi solutions available today. GO’s xRF engine is based on a patent-pending implementation of adaptive beamforming and smart antenna signal processing algorithms. On the transmit side, the xRF engine dynamically focuses radio energy towards the client, effectively reducing the amount of multipath the client's receiver is exposed to and increasing the system's range and throughput by 2-3 times compared to existing solutions. www.go80211.com /technology   (294 words)

Bristol Repository of Scholarly Eprints (ROSE) : Down-link beamforming effects on the code orthogonality in UTRA-FDD ... A novel approach in quantifying code orthogonality factor for UTRA-FDD systems is extended in this paper to include the impact of down-link beamforming. The effects of fixed beamforming on code orthogonality is analysed through the aid of real channel data taken from urban cellular environments. The results show a significant overall improvement in code orthogonality with beamforming, especially in the case of an urban large cell hdl.handle.net /1983/150   (266 words)

ECS EPrints Service - Genetic Algorithm Assisted Adaptive Beamforming   (Site not responding. Last check: 2007-10-03) Genetic Algorithm (GA) assisted beamforming techniques are proposed as an alternative to conventional beamforming algorithms. The design of the corresponding GAs is highlighted and the achievable performance is characterised in terms of the Signal-to-Interference Ratio (SIR) and the Signal-to-Interference plus Noise Ratio (SINR). It is demonstrated that an attractive SINR versus complexity trade-off is achievable by the proposed GA-assisted beamformers, provided that the GA parameters are appropriately chosen. eprints.ecs.soton.ac.uk /6950   (171 words)

Title page for ETD etd-02202003-152259 Frequency domain beamforming is studied in this research predominantly through simulation. As an alternative a time domain beamforming is also studied. Minimum Mean Square Error (MMSE) detection coupled with MMSE beamforming is proposed for time varying channels. scholar.lib.vt.edu /theses/available/etd-02202003-152259   (240 words)

Acoustic Imaging - Beamforming - Brüel & Kjær Beamforming is a method of mapping noise sources by differentiating sound levels based upon the direction from which they originate. The method is very quick, allowing a full map to be calculated from a single-shot measurement. Technical Review: Beamforming - No.1, 2004 (bv0056-11) (4014 kb) www.bksv.com /default.asp?ID=3003   (420 words)

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