Topic
Active antenna
About: Active antenna is a research topic. Over the lifetime, 2246 publications have been published within this topic receiving 26493 citations.
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Patent•
20 Jun 2012
TL;DR: The smart dynamic radiation pattern optimising system is a design and technique to actively shape and optimise the radiation pattern of mobile devices controlled by smart RF/Antenna system with signal processing algorithm that works by sensing the change in device proximity environment with nature or property, range, orientation, position, location, signal quality parameters and ambient intelligence to protect the user by controlling radiation exposure, enhance RF signal quality and to save battery power.
Abstract: The smart dynamic radiation pattern optimising system is a design and technique to actively shape & optimise the radiation pattern of mobile device controlled by smart RF/Antenna system with signal processing algorithm that works by sensing the change in device proximity environment with nature or property, range, orientation, position, location, signal quality parameters and ambient intelligence to protect the user by controlling radiation exposure, enhance RF signal quality and to save battery power. Mobile devices are handled in different proximity environment which influence the antenna performance due to electromagnetic interaction based on environments properties that leads to detuning, radiation pattern distortion, impedance mismatch etc which in turn degrades the signal quality. Also change in device orientation according to usage leads to power loss due to polarization mismatch. So when the signal quality degrades the system will sense & compute in an adaptive closed loop manner to actively optimise the radiation pattern according to scenarios. The design consist of (a) a sensor system 220 to determine the change in proximity environment [close vicinity] with sensing its property, sensing multi-direction, dimension, layer, position & range of proximity environment with respect to device, sensing device (antenna) orientation, visual sensing, infrared or thermal vision, user recognition, user head & hand hold effect, location, usage scenarios & operating modes and accordingly generate the trigger signal 230; (b) a processing unit 150 for computing the interrupt control signal 140 according to the nature of trigger signal & existing signal quality parameters; (c) Smart active radiation pattern optimiser 120 that works based on control signal; (d) Antenna system 110 capable of achieving dynamic radiation pattern coupled with radiation pattern optimiser that actively shapes and controls the radiation pattern accordingly to protect the user and also restores radiation according to scenarios to optimise communication. Other aspects of the present invention are the same sensor system 220 is utilised to develop an application that guides the user locate & position the mobile device in living space to achieve optimised performance, protect the mobile device from theft and ambient intelligence to alert & interact with the user.
132 citations
TL;DR: The proposed technique is compared to conventional SM as well as to spatial multiplexing (SMX), and the results indicate that in most cases, ESM provides a substantial performance gain over conventional SM and SMX while reducing the maximum-likelihood (ML) decoder complexity.
Abstract: In this paper, we introduce a new spatial modulation (SM) technique using one or two active antennas and multiple signal constellations. The proposed technique, which we refer to as Enhanced SM or ESM, conveys information bits not only by the index(es) of the active antenna(s), but also by the constellations transmitted from each of them. The main feature of ESM is that it uses a primary signal constellation during the single active antenna periods and some other secondary constellations during the periods with two active transmit antennas. The secondary signal constellations are derived from the primary constellation by means of geometric interpolation in the signal space. We give design examples using two and four transmit antennas and QPSK, 16QAM, and 64QAM as primary modulations. The proposed technique is compared to conventional SM as well as to spatial multiplexing (SMX), and the results indicate that in most cases, ESM provides a substantial performance gain over conventional SM and SMX while reducing the maximum-likelihood (ML) decoder complexity.
124 citations
TL;DR: Today's high-power, fewantenna, sectorized systems will soon be replaced with highly integrated active antenna systems having up to hundreds of individually driven low-power radios operating with very wideband signals.
Abstract: Every new generation of mobile systems should provide higher capacity, serve more users, be more energy efficient, and have lower cost. Radio-access hardware constitutes a major bottleneck for reaching these goals, which is a particularly noticeable issue now that 5G communication systems are being developed. A combination of breakthroughs in communication theory-as in massive multiple input/multiple output (MIMO) [1], highly integrated semiconductor and packaging technologies, and extended spectrum allocations- has enabled a paradigm shift in the way radio hardware will be realized. Today's high-power, fewantenna, sectorized systems will soon be replaced with highly integrated active antenna systems having up to hundreds of individually driven low-power radios operating with very wideband signals.
121 citations
Patent•
14 Mar 2013
TL;DR: In this paper, a two-dimensional (2D) antenna array comprising a number N of antenna elements configured in a 2D grid is configured to communicate with at least one subscriber station.
Abstract: A base station and mobile station communicate using a multiple input multiple output (MIMO) communication. The base station includes a two dimensional (2D) antenna array comprising a number N of antenna elements configured in a 2D grid. The 2D antenna array is configured to communicate with at least one subscriber station. The base station also includes a controller configured to transmit N channel-state-information reference-signal (CSI-RS) antenna ports (APs) associated with each of the N antenna elements. The subscriber station includes an antenna array configured to communicate with at least one base station. The subscriber station also includes processing circuitry configured receives physical downlink shared channels (PDSCHs) from a 2D active antenna array at the at least one base station. The 2D active antenna array includes a number N antenna elements. The processing circuitry further configured to estimate a full CSI associated with the N antenna elements.
115 citations
TL;DR: In this paper, an approach for designing a tunable and steerable antenna model is presented based on a wideband bow-tie radiating element mounted above an active artificial magnetic conductor (AMC).
Abstract: In this letter, an approach for designing a tunable and steerable antenna is presented. The antenna model is based on a wideband bow-tie radiating element mounted above an active artificial magnetic conductor (AMC). The AMC geometry consists of a frequency selective surface (FSS) printed on a thin grounded dielectric slab in which some chip-set varactor diodes are placed between the metallic elements and the backing plane through vias. The resulting antenna can be tuned over the S-Band by simply changing all varactor capacitances through an appropriate biasing voltage. Moreover, this structure can operate a beam scanning over each working frequency by applying an appropriate biasing voltage to the active elements of the AMC surface in accordance to leaky radiation principles. The low-profile active antenna is characterized by an overall thickness of 5.32 mm, which corresponds to approximately lambda/24 at the center of the operating band.
114 citations