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A compact ultra‐high frequency (UHF) ultra‐wideband (UWB) antenna for Television TV white space (TVWS) applications is presented in this study. The proposed radiating body is transformed from a rectangular plate following physical essence revealed by characteristic mode analysis. Modal current distributions and their contributions to the total radiation are further analysed after printing the radiating body onto a thin substrate. It is proved that the structure achieves efficient radiation over a wide range of frequencies by exciting multiple modes. In addition, effects of significant parameters on the antenna performance are discussed, and according to which the geometry is optimised. A prototype is fabricated and measured to verify its ultra‐wide impedance bandwidth and monopole‐like radiation pattern. Realised gain and radiation efficiency over the UHF TV spectrum are also measured. The bandwidth efficiency product against antenna electrical size are analysed and compared with theoretical limit and products of existing designs. [ABSTRACT FROM AUTHOR]

The findings of a TV broadcast spectrum measurement campaign, performed at six different locations on the Hatfield campus of the University of Pretoria, are presented. Since the use of television white spaces (TVWS) could help to alleviate the impending spectrum crunch, the motivation for the study was to identify possibly unused bands for use by emerging technologies, such as cognitive radio, and also to address the hidden node problem associated with spectrum sensing (SS). This was achieved by comparing measured data to both actual TV channel allocations and a geo-location database (GLDB) for the Tshwane metropolitan area (city of Pretoria). Localised measurements indicated that a number of TVWS opportunities existed, with between 216 and 376 MHz of spectrum found to be potentially available for secondary usage. However, a comparison with TV channel allocations (256 MHz free) and the GLDB (96 MHz free) highlighted the effect of the hidden node problem. [ABSTRACT FROM AUTHOR]

In the TV white space, geolocation database techniques are utilized to manage white space devices (WSDs) or secondary users' operations over the digital terrestrial TV (DTT) receiver protection, in which the location-specific maximum power of WSDs is calculated based on location probability. The multiple antennas can also be utilized for WSDs to protect the DTT receivers and simultaneously increase the WSDs' system performance. However, due to the lack of channel information at the transmitter, conventional multiple-antenna-based cognitive radio (CR) techniques cannot be applied to WSD transceivers. In this paper, we develop the transmission strategies for multiple-antenna-based WSDs operating on the geolocation database framework. We analyze the achievable throughput when the WSD receiver exploits zero-forcing (ZF) linear processing under imperfect channel estimation and, based on the analytic results, propose a dynamic WSD transmission strategy in which the number of active transmit antennas and the associated antenna indexes are determined according to the WSD operational parameters obtained from the geolocation database. [ABSTRACT FROM PUBLISHER]

Interest in Long-Term Evolution (LTE) broadcast technology is increasing rapidly. With consumer desire for "Television (TV) Anywhere" at an all-time high, more and more leading mobile operators globally are trialling the LTE Broadcast technology within their networks to start identifying different use cases and scenarios to explore its business potential. Broadcasting is usually efficient if more than one user is receiving from one transmitter. Rooftop reception enables a wide reach from high-power high-tower transmitters, so that broadcasting is efficient for popular TV programs, particularly if transmitters operate in single-frequency network mode. LTE, including LTE Broadcast, is currently designed to operate on low-power low-tower networks. This paper discusses the spectral efficiency and flexibility of LTE Broadcast, which is only efficient when several devices receive the same content stream. Unicast is much more efficient for less popular, so called "long-tail" content. For times when there is only low interest in a certain part of the network, the infrastructure can stop the broadcast and use the resources for unicast content delivery and the spare resources for mobile broadband. Furthermore, the implications of differences in replacement cycles of fixed TV receivers and mobile devices are discussed. A signal adapted to the high radio signal quality of rooftop antennas should be used for the legacy technologies supporting fixed receivers, whereas a signal adapted to the low radio signal quality typical for mobile reception is required. Thus, it is essential to use the most efficient technologies soon after ratification of the standards. Finally, we outline a potential use of existing rooftop antenna installations for LTE modems that can be used for TV distribution and beyond. [ABSTRACT FROM AUTHOR]

A simple internal antenna that combines a planar inverted F antenna (PIFA) and a loop antenna to achieve wideband (BW ∼ 48%) operation in ultra‐high frequency (UHF: 470–771 MHz) band for digital television (DTV) applications is presented. The design allows the installation of an antenna within a TV model, thereby addressing the limitations of space. The 49‐inch DTV is used for the practical implementation experiment. The TV bezel (made of polycarbonate‐acrylonitrile butadiene styrene (PC‐ABS): εr = 3.5; tan δ = 0.005) is used as the substrate for the antenna design. The antenna is placed on the top edge of the TV model. With the combination of the PIFA mode and loop mode operations, the operating bandwidth of the proposed PIFA‐loop antenna is significantly broadened. The measured results show that the proposed antenna has wide bandwidth of about 410 MHz (460–870 MHz) and suitable radiation performance with higher than 2.2 dBi of peak gain and 47% of efficiency within the operating bandwidth. [ABSTRACT FROM AUTHOR]

For buildings, structures and facilities a Lightning Protection System (LPS) is very important. There are some components that affect the effectiveness of LPS. One of the components is the lightning air terminal. With reference to the facilities requiring lightning protection the position, the apparent height, and the angle of protection of lightning air terminals determines the collection volume (CV) of the protected area. The CV of direct strike lightning air terminals can change because of the facility is affected by natural disasters such as seismic tremor and flood. If such natural disasters do happen, there are possibilities that the facilities will not be fully protected from direct lightning strikes. The building and structure could be misalignment after the seismic tremor and flood related to earth movement. So for the safety of equipment and personnel, lightning protection system efficacy assurance is necessary. Therefore, there should be a technique and device to monitor the variation of collection volume afforded by every lightning air terminal on buildings and structures after the occurrence of a natural disaster. This paper presents a new technique as well as a new device to monitor the collection volume variation. A part of the device was obtained from a recycled moveable television antenna. This approach is not only practical, portable and cost effective but also incorporating the idea of environmental protection and recycling of used plastic materials. [ABSTRACT FROM AUTHOR]

This column covers ?industrial strength? software for converting between SEV or LaTeX and Microsoft Word, a source for TV antennas, a reminder of why people may be purchasing a new computer in the next 28 months, and some improvements in methods for keeping laptops secure. Converting Between SEV or LaTeX and Word The Math Utilities from GrindEQ provide extensive, robust capabilities for converting to and from a variety of SEV formats and Microsoft Word. If you need to do such conversions involving more than a page or two of mathematics, this software will easily pay for itself in time saved and frustration avoided. [ABSTRACT FROM PUBLISHER]

The article offers information on decision of the Appellate Division, First Department of the Supreme Court of New York on the case Prince v. City of New York. Topics discussed include claims of violating Excessive Fines clause of the U.S. Constitution for the removal of television antenna, punitive damages caused due to civil trials, and grant of certiorari of the U.S. Supreme Court.

The characteristics of indoor transparent antenna are investigated. The purpose of the antenna is applied for television signal reception which is operating at Ultra High Frequency band. The antenna was made from silver coated polyester film (AgHT-4), the transparent conductive material and it is attached on a layer of glass substrate. The antenna size has width and length of 120mm x 150mm. It was fed by a co-planar waveguide due to the opportunity of low radiation loss and to reduce reflection of the antenna. The frequency range of 500MHz to 800MHz is chosen as it is the UHF television reception band and allocated by Federal Communications Commission. Due to the television station provided in Malaysia, each station have different channel with its own specification frequencies. The channels also are based on the transmitter base station location. Since the proposed project launches at Universiti Teknologi Malaysia, Skudai, Johor, Malaysia so all the channel is following the frequency from GunungPulai, Johor transmitter base station. The channel utilizations are Channel 55 (742-750MHz): TV1, Channel 26 (510-518MHz): TV3, Channel 42 (638-646MHz): NTV7, Channel 44 (654-662MHz): TV9 and Channel 46 (670-678MHz): 8TV. Then, the proposed antenna was designed by using Computer Simulation Software (CST) Microwave Studio to obtain the simulation result. The simulated bandwidth of the antenna obtained is 448MHz (502MHz to 950MHz) with bandwidth of 61.71%. It has a potential to be realized for TV reception because of the omni-directional radiation pattern and gain is more than 2.0 dBi. [ABSTRACT FROM AUTHOR]

The characteristics of a system for video imaging of objects in the 3-mm-wavelength range are presented. A calculation procedure and characteristics of an aspherical single-lens objective that is used for imaging (point scattering function, resolution, and field of vision) are presented. An 8 × 8 array of antenna elements that are loaded with detectors is used for the detection of signals in the image plane. A digital processing unit is used for the detection, control, and input-output of electric signals that form the image. The processing and data-transfer rates of the unit are presented. Test experiments on imaging of simple objects (one or several metal spheres with different diameters) are performed in the active radar regime using the proposed system and monochromatic signal. [ABSTRACT FROM AUTHOR]

The frequency spectrum offered by television white spaces provides an attractive solution to supplying extra bandwidth within large wireless local area networks or wireless backhaul links. However, it is still necessary to ensure for deployment purposes that the primary users, broadcasting services in this case, do not interfere with the white space devices but more importantly that the white space devices do not interfere with the television receivers or television re-transmitters. Given the increased use of vertical polarization as opposed to horizontal polarization in digital television transmission, this paper investigates the benefits of using horizontal as opposed to vertical polarization for white space devices operating within a restricted area. For white space devices such as access points or backhaul links placed at a high height, use of horizontal polarization will reduce their vulnerability to interfere with the primary user regardless of what polarization it has, while also they will be less susceptible to interference from the primary user in locations where vertically polarized television transmitters are deployed. [ABSTRACT FROM PUBLISHER]

Inside of the new communication model determined by the multimedia convergence, TV second screen apps for mobile devices are increasing slowly in Spain. The one with higher implantation and range is Ant 3.0, hence its interest to be analyzed. This paper invites to know, from the practice, how it works and the main services provided by the first contents synchronized app in Spain after having an approach to the concept of second screen activity. So the field work has lied in following a second screen session and a broadcast of Gran Hotel series episode has been chosen. As a result, Ant 3.0 app gets defined as a complete second screen experience with interactive contents that develops the spectator's loyalty and makes him being involved, in this case, in solving the mysteries of the plot. [ABSTRACT FROM AUTHOR]

Abstract: Polarized multi-antenna systems are an effective solution for reducing inter-antenna spacing while still maintaining low inter-antenna correlation. Traditionally, only dual-polarized antenna systems are used for polarized transceivers. In this paper, tri-polarized antenna systems are investigated. Starting from the polarization mechanisms in the wireless propagation channel, it is shown that dual-polarized MIMO systems show high sensitivity to the transmitter and receiver orientation, which may be very critical in practical applications. Tri-polarized MIMO systems are introduced as a solution to obtain a robust MIMO performances, which are independent of the transmitter and receiver orientation. The performances of dual- and tri-polarized MIMO systems are evaluated on real-world measured channels, and the limits of each of these systems is highlighted. [Copyright &y& Elsevier]

The incorporation of new services in handheld devices, such as the Digital Video Broadcast—Handheld (DVB-H) operating at the lower ultrahigh-frequency (UHF) band poses a challenge for antenna designers. Wideband small antennas or electrically tunable narrowband small antennas are needed to fulfil the performance requirement. It is well known that below 900 MHz the operation of embedded mobile terminal antennas is based on utilizing the whole structure of the terminal as a radiator. However, even this way reaching the whole required impedance bandwidth of about 46% at about 0.61-GHz center frequency is possible only either with clamshell-type terminals used as thick dipoles by feeding them from the hinge or with “large tablet”-sized terminals. With the popular smartphone-sized terminals with a monoblock structure the available bandwidth with good total efficiency is clearly smaller. We study the options to implement antennas for smartphone-type mobiles for receiving digital TV broadcasts at about 0.47–0.75-GHz frequencies. The mainly studied technology is the nonresonant capacitive coupling element (CCE)-type antennas having one of the smallest achieved volume-to-bandwidth ratios. We show that for a fixed-frequency antenna with a volume of less than a few cubic centimeters the total efficiency will become rather low due to moderate matching level, but the requirement of the DVB-H standard for the realized gain can easily be met. Additionally, we show that by having switching between two bands, one can implement a dual-antenna configuration with small total volume and significant multiple-input–multiple-output (MIMO) gain. Furthermore, we study the very important effect of the user's hands on the antenna performance and find that the effect can range from some increase of the total efficiency due to improved matching to significant losses caused by the hands. Finally, we propose some possible ways ahead in solving this very challenging antenna design problem. [ABSTRACT FROM PUBLISHER]

The structure of the array antenna for the reception antenna of the digital terrestrial television broadcasting in Japan is optimized by PSO algorithm. The unbalanced fed ultra low profile inverted L antenna is used as the driven element and two wires are located at the forward and backward directions of the driven element. In the case of antenna size of 170 mm by 325 mm by 29 mm, the return loss bandwidth less than -10 dB is satisfied at the whole broadcasting frequency band (240 MHz) and the directivity of 5.44 dBi to 7.19 dBi is obtained. In the numerical analysis, the electromagnetic simulator WIPL-D based on the method of moment is used. [ABSTRACT FROM AUTHOR]

Earlier bi-circular polarization technique for implementing a 3D TV with two picture tubes showed to yield reduced crosstalk compared to the popular linear polarization technique. This paper reports to modify the implementation of bi-circular polarized technique with just one picture tube incorporating electro-oplically driven polarization. The crosstalk resulted in this implementation is shown to be much reduced. Secondly, a 3D TV system transmitting stereo pair of images and recovering sectional images in the receiver is proposed. The display of sectional images, for naked eye viewing, is taken to volumetric display in a display lank and alternatively to an electro-optically driven vari-focal lens system. The high speed RISC processor in the receiver performs stereo matching of adaptive windows bearing a cluster of edges on the pair of images and produces sectional images. As the transmission of stereo images is simpler than other methods this technique offers another feasible way towards implementing 3D TV. [ABSTRACT FROM AUTHOR]

A scattering technique for measuring reactive antenna input impedance is described. The antenna scattering is measured with three different loads: an open circuit, a conjugate match, and a reactive match. The load reactances tune the antenna into resonance at the measurement band. Theory and error considerations are presented, as well as measurement results of two ultra high frequency radio frequency identification antennas. The measurements were performed in a gigahertz transverse electromagnetic mode cell. The measured impedances are within about 10% of the simulated values for a dipole-like antenna. The results of a planar inverted-F antenna are somewhat more complex, but also supported by the presented simulations and the coaxial impedance measurement results. [ABSTRACT FROM AUTHOR]

This paper examines the limits that must be imposed on single and multiple fixed cognitive broadband devices (BDs) transmitting simultaneously on multiple unused TV channels in order to avoid interference with the reception of licensed TV channels. Single and multiple fixed BDs are assumed to radiate 4 W peak power relative to an isotropic source and transmit within 10 meters of the nearest digital television (DTV) set antenna. The power and separation limits are shown to depend on whether BDs are licensed, on whether mandated minimum front-end performance specifications for DTV sets are in place, and on the definition of an "unused channel." Short and long-term general conclusions are drawn regarding the maximum allowable directional power and regarding taboo channels for interference-free coexistence with DTV sets. It is shown that unlicensed BDs would result in the least efficient use of the available DTV spectrum because the "worst case" interference limits must be imposed in an unlicensed environment. The most efficient utilization of the DTV spectrum would be achieved if BDs were licensed and then allowed to migrate, together with DTV channels, into two blocks of contiguous channels, one for DTV and one for BDs. [ABSTRACT FROM AUTHOR]

The interference between first adjacent channels N and N ± 1 in an environment of distributed on-channel transmitters is analyzed. Channel N uses a single transmitter and the adjacent channels N ± 1 use distributed on-channel transmitters. The conditions and planning factors that will permit reliable implementation of ACI-free areas across all applicable signal levels are presented. The effect of antenna gain, height and power relative to the physical separation between channels N and N ± 1 are analyzed and the regions of adjacent channel interference (ACI) are delineated. [ABSTRACT FROM AUTHOR]

The article discusses the model used for explaining the interference between outgoing and reflected waves, resulting to the formation of standing waves. The reflected waves can interfere with incident waves, producing patterns of constructive and destructive interference that lead to standing waves. Standing waves are commonly found in wind and string instruments, television aerials and flags. Various types of models and its operation are cited to demonstrate and explain the interference am

Studies the interference problems in actual terrestrial television scenarios. Radiation elements used for broadcasting digital television and analog television signals; Restrictions on the use of antennas to protect analog services; Dependence of the required power ratio on the radiation pattern of antennas.

Analyzes the reradiation of a tapered tower section supporting a side-mounted digital television (DTV) broadcast antenna and the correspomding azimuth pattern. Characteristics of the reradiation; Impact of reradiation on DTV receiver; Formation of the antenna azimuth pattern; Comparison with vertically oriented tower legs.

Outlines improvements in the modeling, methods and procedures now in use for prediction and measurement of digital television service in the United States. Effects of the impedance mismatches between the antenna and the tuner; Modifications in the Longley-Rice algorithm for prediction of signal level at various heights above the ground; Addition of space diversity reception and directional pattern steering.

Presents an overview of the slot, panel and superturnstile types of UHF television antennas. Types of slot antennas; Operating principle; Elevation pattern shaping; Azimuth pattern shaping; Operating principle of panel systems; Advantages and limitations; Narrowband panels; Mechanical structure; Operating principle of superturnstile antennas; Advantages and limitations.

Reports on the azimuth pattern analysis of a side-mounted digital television (DTV) broadcast antenna. DTV antenna and tower environment; Details of the tower design; Scattering analysis results; VSB modulation; Receiver clock recovery and timing.

A radial line slot antenna (RLSA) is a slotted waveguide planar array proposed for DBS subscriber antennas. Its predicted conductor loss is almost negligible. The RLSA has extremely simple structure. It utilizes nonuniform slots which cancel the tapered aperture illumination associated with radial outward traveling wave excitation. An efficiency of more than 80% has been realized in RLSAs released for commercial use in Japan. The high potential of RLSAs in term of electrical and cost performance has stimulated advanced design for various applications, such as linearly polarized RLSAs and dual polarized RLSAs. One challenging topic is the design of low sidelobes for RLSA. This paper presents the basic design and measured performance of low-sidelobe RLSAs. A first sidelobe level of less than -25 dB and an antenna efficiency of 65% are realized. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 1, 80(7): 70–76, 1997 [ABSTRACT FROM AUTHOR]

The article discusses a study which examines the extent to which television antennas are permitted in housing developments in the U.S. following the Federal Communications Commission 's (FCC) adoption of a revised must carry rule requiring cable operators to provide A/B switches for subscribers. The study analyzes the deed restrictions that prohibit outdoor antennas. It is noted that real estate developers make communications policy decisions as reflected in the presence of such restrictions.

Proposes a theoretical computation method for a digital TV transmitter coverage probability. Theory in computing the coverage probability; Results of evaluating the reliability of the analytical method; Conclusions.