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| | In today competitive environment, corporations are working with innovate and new suggestions to remain a stage ahead of their competitors. Brand identification, is the way to go forward, and which can help the firm to create itself strongly in the market place. A manufacturer helps to entice the likely concentrate on audience in huge figures. For instance, folks all above the earth desire to order branded sneakers these types of as Reebok or Nike more than other sneakers, since they are of significant top quality and also huge brands. Consequently, they do not brain paying out a larger price for it. Even so, in buy to produce a model, there are numerous factors which companies have to very carefully evaluate and execute in the appropriate path to gain maximum benefits. The entire process of making awareness for a particular manufacturer is also generally referred to as the promoting strategy. <br><br>Marketing products and solutions of a variety of corporations has improved over the many years. Commercials are a good way of making model recognition for the likely concentrate on viewers. Whilst creating a top quality ad, distinctive ideas and views [http://Www.Dict.cc/englisch-deutsch/assistance.html assistance] to make a particular advertisement preferred amid the normal general public. A superior and innovate tag line completes the advertising and marketing and productively achieves in building a brand name picture and producing the general public knowledgeable of their particular solution or services which they offer you to their consumers. <br><br>Symbol Merchandise is also common between the several businesses, as the logos of the respective models are embedded on the advertising solutions to attain a higher visibility, which indirectly gains the respective business to make awareness about its particular brand name.<br><br>Marketing solutions or promo goods is a person of the most well-known methods and strategies to produce consciousness about a respective manufacturer. Promotional merchandise this sort of as t-shirts, mugs, watches, calendars are dispersed cost-free of charge to the [http://search.un.org/search?ie=utf8&site=un_org&output=xml_no_dtd&client=UN_Website_en&num=10&lr=lang_en&proxystylesheet=UN_Website_en&oe=utf8&q=prospective+focus&Submit=Go prospective focus] on audience in purchase to make them mindful of the unique model. These products are dispersed by arranging exciting and entertaining game titles and competitions at buying malls and other community destinations, exactly where there is a increased chance to get hold of the respective concentrate on audience. These products and [http://www.reddit.com/r/howto/search?q=solutions solutions] are distributed as a reward to the participants for participating in the competitions. Companies have appear up with numerous new and impressive methods to continue to keep their contributors engrossed and entertained as a result of these exciting video games and competitions. <br><br>Apart from these advertising and marketing presents, companies also take initiatives to offer enable and support in direction of the culture. For this intent they set up general public gardens and plant trees which make their firm observed by the general public as an corporation which usually takes steps to satisfy its social obligation toward the surroundings and the individuals living in the culture. <br><br>Consequently, all these techniques, innovative procedures and items are utilised and dispersed with good precision so that it offers out the sought after effects for the branded merchandise, support or firm in the extended operate.<br><br>If you liked this article as well as you want to obtain more details relating to [http://tinyurl.com/odudrnx http://tinyurl.com/odudrnx] kindly go to our own site. |
| [[Image:Traqueur acquisition.JPG|thumb|Array of four axial-mode helical antennas used as a satellite tracking-acquisition antenna, Pleumeu-Bodou, France]]
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| [[Image:helical antenna principle.png|thumb|right|180px|Axial-mode helical antenna:<BR> ''(B)'' Central support,<BR>''©'' Coaxial cable feedline,<BR>''(E)'' Spacers/supports for the helix,<BR>''(R)'' Reflector ground plane,<BR>''(S)'' Helical element]]
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| {{distinguish|spiral antenna}}
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| A '''helical antenna''' is an [[antenna (electronics)|antenna]] consisting of a conducting wire wound in the form of a [[helix]]. In most cases, helical antennas are mounted over a [[ground plane]]. The [[feed line]] is connected between the bottom of the helix and the ground plane. Helical antennas can operate in one of two principal modes: normal mode or axial mode.
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| In the ''normal mode'' or ''broadside'' helix, the dimensions of the helix (the diameter and the [[pitch (screw)|pitch]]) are small compared with the [[wavelength]]. The antenna acts similarly to an [[electrically short]] [[Dipole antenna|dipole]] or [[Monopole antenna|monopole]], and the [[radiation pattern]], similar to these antennas is [[Omnidirectional antenna|omnidirectional]], with maximum radiation at right angles to the helix axis. The radiation is [[linear polarisation|linearly polarised]] parallel to the helix axis.
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| In the ''axial mode'' or ''end-fire'' helix, the dimensions of the helix are comparable to a wavelength. The antenna functions as a [[directional antenna]] radiating a beam off the ends of the helix, along the antenna's axis. It radiates [[Circular polarisation|circularly polarised]] radio waves.
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| ==Normal-mode helical==
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| Radiating at 90 degrees from the axis of the helix this design is efficient as a practical reduced-length radiator when compared with the operation of other types such as base-loaded, top-loaded or centre-loaded whips. They are typically used for applications where reduced size is a critical operational factor.
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| These simple and practical "Helicals" were primarily designed to replace very large antennas. Their reduced size is therefore most suitable for Mobile and Portable [[High-frequency]] (HF) communications in the 1 MHz to 30 MHz operating range.
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| [[Image:Uhf cb wit rubber ducky exposed.jpg|thumb|left|A common form of normal-mode helical antenna is the [[Rubber Ducky antenna]] used in portable radios. The loading provided by the helix allows the antenna to be shorter than its electrical length of a quarter-wavelength.]]
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| Usually wound in a linear "spiroidal" pattern (constant parallel spaced turns) providing consistent uniform radiation as a reduced sized equivalent in respect to the standard 1/4 wave antenna. This concept was proven practical by an Australian design.{{Citation needed|date=August 2010}}
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| An effect of this type of concertinaed 'reduced size 1/4 wave' is that the matching [[Impedance matching|impedance]] is changed from the nominal 50 ohms to between 25 to 35 ohms base impedance. This does not seem to be adverse to operation or matching with a normal 50 ohm [[transmission line]], provided the connecting feed is the electrical equivalent of a 1/2 wave at the frequency of operation.
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| Another example of the type as used in mobile communications is "spaced constant turn" in which two or more different linear windings are wound on a single former and spaced so as to provide an efficient balance between [[capacitance]] and [[inductance]] for the radiating element at a particular resonant frequency.
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| Many examples of this type have been used extensively for 27 MHz [[CB radio]] with a wide variety of designs originating in the US and Australia in the late 1960s. Multi-frequency versions with plug-in taps have become the mainstay for multi-band [[Single-sideband modulation]] (SSB) HF communications.
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| Most examples were wound with [[copper]] wire using a [[fibreglass]] rod as a former. This flexible radiator is then covered with [[heat-shrink tubing]] which provides a resilient and rugged [[waterproof]] covering for the finished mobile antenna.
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| These popular designs are still in common use today (2010) and have been universally adapted as standard FM receiving antennas for many factory produced motor vehicles as well as the existing basic style of aftermarket HF and VHF mobile helical. The most common use for broadside helixes is in the [[Rubber Ducky antenna]] found on most portable VHF and UHF radios.
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| ==Axial-mode helical==
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| [[Image:Hammer Ace SATCOM Antenna.jpg|thumb|End fire helical satellite communications antenna, Scott Air Force base, Illinois, USA. Satellite communication systems often use [[Circular polarisation|circularly polarised]] radio waves, because the satellite antenna may be oriented at any angle in space without affecting the transmission, and axial mode (end fire) helical antennas are often used as the ground antenna.]]
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| In the ''axial mode'', the helix dimensions are at or above the wavelength of operation. The antenna produces radio waves with [[circular polarisation]]. The [[main lobe]]s of the [[radiation pattern]] are along the axis of the helix, off both ends. Since in a directional antenna only radiation in one direction is wanted, the other end of the helix is terminated in a flat metal sheet or screen reflector to reflect the waves forward.
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| In [[radio transmission]], circular [[Polarisation (waves)|polarisation]] is often used where the relative orientation of the transmitting and receiving antennas cannot be easily controlled, such as in [[animal tracking]] and [[Satellite communications|spacecraft communications]], or where the polarisation of the signal may change, so end-fire helical antennas are frequently used for these applications. Since large helices are difficult to build and unwieldy to steer and aim, the design is commonly employed only at higher frequencies, ranging from [[VHF]] up to [[microwave]].
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| The helix in the antenna can twist in two possible directions: right-handed or left-handed, as defined by the [[right hand rule]]. In an axial-mode helical antenna the direction of twist of the helix determines the polarisation of the radio waves: a left-handed helix radiates left-circularly-polarised radio waves, a right-handed helix radiates right-circularly-polarised radio waves. Helical antennas can receive signals with any type of linear polarisation, such as horizontal or vertical polarisation, but when receiving circularly polarised signals the handedness of the receiving antenna must be the same as the transmitting antenna; left-hand polarised antennas suffer a severe loss of [[gain]] when receiving right-circularly-polarised signals, and vice versa.
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| The dimensions of the helix are determined by the [[wavelength]] λ of the radio waves used, which depends on the [[frequency]]. In axial-mode operation, the spacing between the coils should be approximately one-quarter of the wavelength (λ/4), and the diameter of the coils should be approximately the wavelength divided by pi (λ/π). The length of the coil determines how [[directional antenna|directional]] the antenna will be as well as its gain; longer antennas will be more sensitive in the direction in which they point.
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| Terminal [[Electrical impedance|impedance]] in axial mode ranges between 100 and 200 ohms. The resistive part is approximated by:
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| :<math> R \simeq 140 \left ( \frac{C}{\lambda} \right )</math>
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| where R is resistance in ohms, C is the circumference of the helix, and λ is the wavelength. Impedance matching to the cable C is often done by a short [[stripline]] section between the helix and the cable termination.
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| [[Image:helical antenna.jpg|thumb|Helical antenna for [[wireless LAN|WLAN]] communication, working frequency app. 2.4 GHz]]
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| The maximum directive gain is approximately:
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| :<math> D_o \simeq 15 N \frac{C^2 S}{\lambda^3} </math>
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| where N is the number of turns and S is the spacing between turns.
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| The half-power beamwidth is:
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| :<math> \text{HPBW} \simeq \frac{52 \lambda^{3/2}}{C \sqrt{NS}}\, \text{degrees}</math>
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| The beamwidth between nulls is:
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| :<math> \text{FNBW} \simeq \frac{115 \lambda^{3/2}}{C \sqrt{NS}}\, \text{degrees}</math> | |
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| ==See also==
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| *[[Telstar]]
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| ==References==
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| *John D. Kraus and Ronald J. Marhefka, "Antennas: For All Applications, Third Edition", 2002, McGraw-Hill Higher Education
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| *Constantine Balanis, "Antenna Theory, Analysis and Design", 1982, John Wiley and Sons
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| *Warren Stutzman and Gary Thiele, "Antenna Theory and Design, 2nd. Ed.", 1998, John Wiley and Sons
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| ==External links==
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| *[http://www.antenna-theory.com/antennas/travelling/helix.php Helical Antennas] Antenna-Theory
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| {{Antenna_Types}}
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| {{DEFAULTSORT:Helical Antenna}}
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| [[Category:Radio frequency antenna types]]
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| [[Category:Helices]]
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Marketing solutions or promo goods is a person of the most well-known methods and strategies to produce consciousness about a respective manufacturer. Promotional merchandise this sort of as t-shirts, mugs, watches, calendars are dispersed cost-free of charge to the prospective focus on audience in purchase to make them mindful of the unique model. These products are dispersed by arranging exciting and entertaining game titles and competitions at buying malls and other community destinations, exactly where there is a increased chance to get hold of the respective concentrate on audience. These products and solutions are distributed as a reward to the participants for participating in the competitions. Companies have appear up with numerous new and impressive methods to continue to keep their contributors engrossed and entertained as a result of these exciting video games and competitions.
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