Radio Equipment, Antenna, Towers and Waveguides PDF
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This document provides detailed information about radio equipment, antennas, towers, and waveguides, including various types, configurations, and components. It also covers topics like microwave transmission and different types of radio equipment.
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RADIO EQUIPMENT, ANTENNA, TOWERS AND WAVEGUIDES Module 2 UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT FM Microwave used an app...
RADIO EQUIPMENT, ANTENNA, TOWERS AND WAVEGUIDES Module 2 UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT FM Microwave used an appropriate multiplexing equipment capable of simultaneously carrying fro a few narrowband voice circuits up to thousands of voice and data circuits. MW radios can also be configured to carry high speed data, facsimile, broadcast quality audio and commercial television signals The baseband is the composite signal that modulates the FM carrier and may comprise one or more of the following: 1. Frequency-division-multiplexed voice-band channels 2. Time-division-multiplexed voice- band channels 3. Broadcast-quality composite video or picturephone 4. Wideband data UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT Baseband IF section also known as signal interface/processing module. This accepts the channels inputs to be sent to the other sites, as well as contains the output ports sent from the other terminal. This may contains LED displays proving the status of the system performance, interfaces for computers, service telephone and switches for the control of the power and parametric settings of the link. This module may includes the following : MULDEM, FEC, Modulator /Demodulator and Diplexer. It is usually independent with the carrier frequency. Most modern microwaves radios is in modular type. Image from: http://tso-sy.com/products/radio/microwave.php UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT Image from: https://vdocuments.mx/ceragon- fibeair-ip-10g-installation-guide.html UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT CONNECTORS BNC Connector TNC Connector SMA Connectors Image Source: https://en.wikipedia.org/ N Type Connector F Type Connector UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT RF Section contains all components in the microwave link responsible to the actual transmission and reception in the microwave frequency range. Nowadays, some of the RF units (RFU) are installed behind the parabolic antenna and even in directly mounted on the feed of the antenna, eliminating the need of the waveguive. Cable connections in the RF sections can be classified according to the Image from: frequency that they carry. http://simcom07.blogspot.com/2011/08/digital-microwave- communication.html UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT TRANSMIT The transmit power is the RF power coming out of the POWER antenna port of a transmitter. It is measured in dBm, Watts or milliWatts and does not include the signal loss of the coax cable or the gain of the antenna. RECEIVE SIGNAL Is the actual received signal level (usually measured in LEVEL (RSL) negative dBm) presented to the antenna port of a radio receiver from a remote transmitter. GTX FSL GRX EIRP IRL TX PT RSL RX TLTX TLRX UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT RECEIVER Is the weakest RF signal level (usually measured in SENSITIVITY negative dBm) that a radio needs receive in order to demodulate and decode a packet of data without errors. SIGNAL-TO- Is the ratio (usually measured in dB) between the signal NOISE RATIO level received and the noise floor level for that particular (SNR) signal. The SNR is really the only thing receiver demodulators really care about. Unless the noise floor is extremely high, the absolute level of the signal or noise is not critical UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT To insure a link carrying information does not fail and achieve the reliability objectives, protection methods are employed to provide a link integrity. The most common protection Image from: http://simcom07.blogspot.com/2011/08/digital- microwave-communication.html method is using hot stand-by system which would immediately catch the operation if the components or path problem primary link fails Image from: https://telecompractice.blogspot.com/2019/03/zte- mw-nr8250-typical-configurations.html UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT There are three basic radio configurations used in microwave communications systems: ALL INDOOR All active components are located inside a building or shelter, only the antenna is outdoor. Thus, allowing easy maintenance and upgrades—without requiring tower climbs, for instance. Being farther from the antenna may introduce higher transmission line losses than other configurations. ALL OUTDOOR All electronics are mounted outside, eliminating the need and cost for indoor space. However, because they are located on the tower, they can be difficult to access for maintenance or upgrades, requiring tower climbs. In some cases, rooftop access mitigates this challenge. SPLIT-MOUNT Electronics are split into an outdoor unit (ODU) and indoor unit (IDU), eliminating transmission line losses with easy maintenance of the IDU. However, it also combines the disadvantages of the other two configurations by requiring indoor storage and tower climbs for the ODU. UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT ALL INDDOR Image from: https://www.slideshare.net/AviatNetworks/aviat -networksmicrowavetechnologyoptions22- july13 UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT ALL OUTDOOR Image from: https://www.daenotes.com/electronics/microwave- radar/digital-microwave-communication-equipment UNIT 1 – Module 2 ECE EL 11 RADIO EQUIPMENT SPLIT-MOUNT Image from: https://www.daenotes.com/electronics/microwave- radar/digital-microwave-communication-equipment UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS Microwave Transmission is the transmission and reception of information via microwaves, and it could be composed of voice, data, television, telephony or radio signals. Antennas must be designed to suit the following key parameters of EM waves: Frequency: The rate of the wave’s oscillation, measured in Hertz (Hz). Amplitude: The strength or power level of the wave. Phase: The particular point in the cycle of a waveform, measured in Image Source: https://arstechnica.com/information- technology/2016/11/private-microwave-networks- degrees. financial-hft/ Polarization: The orientation of the electric field driving the wave Antennas are devices that radiate or receive EM waves of certain frequencies. UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS The antenna is a transition or interfacing between a guided medium such as a cable or waveguide and the open air (or free space). An antenna designed to radiate and receive microwave frequencies, therefore, is called a microwave antenna. Types of the Microwave Antennas: Horn/Aperture Antenna, Parabolic/Dish Antenna, Slotted (leaky-wave) antenna, Dielectric lens antenna, Printed (patch or microstrip antenna, and Phase Array Antenna UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS Highly directional antennas such as parabolic dishes used in point-to-point radio links. For lower frequencies around ≤11 GHz, microwaves can be propagated over long distances using a larger long-haul antennas and thus provide connection to the network terminal stations from remote areas. Higher frequencies above 11 GHz propagated over lesser distances usding smaller short-haul antennas, providing connection much appropriate to urban areas. UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS Waveguide Feed – Connects the antenna to the wave guide. Horn Feed – Directs the EM wave into the focus of the parabolic reflector. Image from: http://ael.cbnu.ac.kr/lectures/graduate/%EC%B4%88%EA%B3%A0 %EC%A3%BC%ED%8C%8C%ED%86%B5%EC%8B%A0%EC%8 B%9C%EC%8A%A4%ED%85%9C%EC%84%A4%EA%B3%84/20 19-2/week-09-parabolic-reflector-antenna-design/parabolic- reflector-theory.htm UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS Parabolic reflector – The reflective surface of the parabolic dish used to collect or project the EM waves. Radome – Weatherproof front covering of the antenna used to protects the inside surface of the parabolic antenna. Particularly useful for large, long-haul microwave antennas that already heavy Shroud – The side covering of the antenna. This allows antennas with long horn feed also be protected. This also reduces interference to and from other antennas mounted closely. UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS Also, a radome is use to reduce windloading and protect the feed assembly from damage. The material selection, shape and thickness are critical to avoid degrading the performance of the antenna. Image Source: https://www.talleycom.com/viewProduct ?rlProdNum=RFSUXA8-65AC1S1 Image Source: https://www.rfwireless- world.com/Terminology/Advantages-and- Disadvantages-of-Antenna-Radome.html UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS Mount serve he structural interface between the antenna and the mounting pole on the tower. It usually includes the azimuth and elevation adjustment mechanisms Mounting Assembly – This clamps the antenna to the mast or tower. This allows the antenna to be swung between left to right. Vertical tilt screw – This allows the antenna be pointed upward or downward, depending the antenna orientation. Image Source: Microwave Antenna Alignment: https://www.slideshare.net/lob Video link https://www.youtube.com/watch?v=7FBS_K0sXdc oalfaleal/uca-uni-july-2013 UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS Image Source: https://www.saftehnika.com/files/downloads/611d60e5-6676-e211- bc32-0050569aa6cf/Antenna_alignment_White_Paper_SAF_Aug_2017.pdf UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS Important Characteristics : Gain Directivity Beamwidth Radiation Pattern Polarization Side lobe and Front-to-back Ratio Voltage Standing Wave Ratio (VSWR) Frequency Operating Range Image Source: https://www.semanticscholar.org/paper/Effect-of-a- Mounting, weight and width Central-Antenna-Element-on-the-and-of-Z%C3%BA%C3%B1iga- Haridas/d0a45625fcc6f14739b2e4d89787efaadfb3b151/figure/1 loading UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS GAIN Although there are many types of antennas, most point-to-point microwave systems utilize parabolic antennas in order to achieve the required gain and reduce interference. The standard formula for computing parabolic antenna gain assumes 55% illumination efficiency of the antenna’s capture area GdB = 7.5 + 20logf GHz + 20logD ft GdB = 17.8 + 20logf GHz + 20logD m UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS Operational wind load. The maximum wind speed at which an antenna will continue to maintain the majority of the beam energy on the antenna at the other end of the link” Survival wind load. The maximum wind speed a microwave antenna can experience without permanent damage Angular movement The shifting or twisting of a microwave antenna as a result of environmental conditions, which can result in lower signal strength or even total link failure. UNIT 1 – Module 2 ECE EL 11 ANTENNA AND ANTENNA TOWERS UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION Microwaves can propagate through a guided medium, such as a transmission line, examples are cables or waveguide. Can also be propagated through an HF Coaxial Cables unguided medium as plane waves in free Image from: https://www.hitachi- space and through the atmosphere. metals.co.jp/e/products/infr/in/wireless_an tenna.html Image from: https://www.fairviewmicrowave.com/n- fairview-microwave-releases-new-lines- of-flexible-waveguides-operating-to-40- Waveguides ghz-over-nine-bands.aspxl UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION COAXIAL CABLE is appropriate in the applications using frequencies up to or just above 2 GHz. above this range, most lengths become too lossy to be of practical use. Transmission Line Losses (TLL) losses due to the transmission medium used in connecting radio equipment to antenna. Taken from the specs of the waveguide/coax used. This is the amount of loss, usually expressed in dB per unit length (dB/ft or dB/m) of signal as it travels in the medium. UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE A hallow metallic physical conducting pipes as the transmission medium designed to carry and contrains the EM waves of a microwave signal; unlike a cable, waves propagate along it without an inner conductor. A microwave waveguide can handle large amount of power and with a single conductor is a high pass filter; thus these structures have a cutoff frequency. Microwave signal travels through guided media in different modes. Types of single conductor waveguides are: Rectangular Waveguide, Circular Waveguide, Elliptical Waveguide, Ridged Waveguide and Corrugated Waveguide. UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION Rectangular Waveguide Elliptical Waveguide Image from: Circular Ridged Waveguide https://www.primus Waveguide electronics.com/pr oducts/ew90/ Image from: https://www.indiamart.com/proddetail/bras s-waveguide-4110877112.html Image from: https://www.advancedmicro wave.com/double-ridged- components/double-ridge- Image from: waveguide-formed-bends https://www.researchgate.net/figure /Corrugated-waveguide-made-from- stacked-rings-a-Schematic-view-of- a-corrugated_fig3_276868089 Corrugated Waveguide UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION Choice of waveguide is dictated by: (a) the desired operating frequency band, (b) the amount of power to be transferred, and (c) the amount of transmission attenuation that can be tolerated. Attenuation in waveguide can be caused by dielectric loss (if the waveguide is full of dielectric) or by conductor loss due to the metal structure’s finite conductivity. The maximum attenuation values is measured in decibels per meter (dB/m) and provided by manufacturer. The various modes of operation available depend on the desired frequency, as well as the size and shape of the waveguide itself UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE COUPLING -is the desirable or undesirable transfer of energy from one medium, such as a metallic forward-wave coupler - if the wire or an optical fiber, to another medium. coupled signal is traveling in Microwave couplers are devices which divert a the same direction as the through signal. fraction of the signal on one transmission line backward-wave” coupler -if in to another transmission line opposition to the “forward- wave” coupler. Image from: http://www.dolphmicrowave. com/product/multi-hole- waveguide-directional- couplers/ UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION DIRECTIONAL 𝐼𝑛𝑠𝑒𝑟𝑡𝑖𝑜𝑛 𝐿𝑜𝑠𝑠 𝐼𝐿 = 10𝑙𝑜𝑔 𝑃𝑖 , 𝑑𝐵 𝑃𝑟 COUPLER LOSSES 𝑃𝑖 𝐶𝑜𝑢𝑝𝑙𝑖𝑛𝑔 𝐿𝑜𝑠𝑠 𝐶 = 10𝑙𝑜𝑔 , 𝑑𝐵 𝑃𝑓 𝑃𝑖 𝐼𝑠𝑜𝑙𝑎𝑡𝑖𝑜𝑛 𝐼 = 10𝑙𝑜𝑔 , 𝑑𝐵 𝑃𝑏 𝑃𝑓 𝐷𝑖𝑟𝑒𝑐𝑡𝑖𝑣𝑖𝑡𝑦 𝐷 = 10𝑙𝑜𝑔 , 𝑑𝐵 𝑃𝑏 UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE FLANGE A waveguide flange is a connector for joining sections of waveguide, and is essentially the same as a pipe flange. Image from: https://www.microwave- link.com/microwave/microwave-waveguide-flange/ UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE FLANGE When joining two waveguide sections the flange types must match to ensure minimal losses. Flanges are usually connected to each other using four or more bolts to keep connection intact. Sample waveguide flange specification sheet: https://www.maurymw.com/pdf/datasheets/wgf lngs.pdf Image from: https://raditek.com/waveguide-flanges.html UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE CONNECTOR It provides attenuation on the signal as provided in the specification sheet Sample Specification sheet: (insertion loss) https://www.commscope.com/globalas sets/digizuite/283663-p360-1127sc- external.pdf UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE TO COAX ADAPTER Image from: https://www.antenna- theory.com/tutorial/waveguides/w aveguide.php Image from: https://www.spinner- group.com/en/news/news- centre/578-waveguide-to-coaxial- adaptors-start-testing-faster UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE Microwave terminations are the precise loads required MATCHED in microwave measurement and calibration systems. TERMINATION In making measurement of waveguide component it is often desirable to absorb the power propagated down the waveguide. These are designed in such a way to absorb the maximum energy without having appreciable reflection assuring low VSWR. Image from: https://www.indiamart.com/prodd etail/matched-termination- 14852366473.html UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION The attenuators are basically RF passive devices which WAVEGUIDE control power levels in microwave system by absorption or ATTENUATORS reducing the power of the signal. Attenuator which attenuates the RF signal in a waveguide system is referred as waveguide attenuator. There are two main types fixed and variable. They are achieved by insertion of resistive films. Variable Waveguide Attenuators Image from: https://www.pasternack.co Image from: m/pages/RF-Microwave- https://www.atmmicrowave.c and-Millimeter-Wave- om/waveguide/attenuator/fix Products/waveguide- ed-precision-high-power/ attenuators.html Fixed Waveguide Attenuators UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE BENDS -Used to direct high frequency signals propagating through a waveguide in a specific direction. These bends allow the change in direction of a signal within a waveguide, with minimal loss, reflection and distortion of the electric and magnetic fields Types of Waveguide bends: Image from: https://www.novuslight.com/fairview- a.) Waveguide E bends waveguide-bends-now-support- b.) Waveguide H bends frequencies-to-90-ghz_N6253.html c.) Waveguide Twist Image from: https://www.pasternack.com/pages/RF- Microwave-and-Millimeter-Wave- Products/waveguide-bends.html UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE E BEND An E-bend changes the E-Field (Electric Field) of the propagating signal. In order to minimize reflections, the radius of the bend should be greater than two wavelengths of the signal. WAVEGUIDE H BEND An H-bend changes the H-Field (Magnetic Field) of the propagating signal. In order to minimize reflections, the radius of the bend should be greater than two wavelengths of the signal Image from: https://www.everythingrf.com/com munity/what-is-the-difference- between-e-and-h-bend UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE TWIST A gradual twist in the waveguide is used o turn the polarization of the waveguide and the waveform. In order to avoid excessive distortion on the waveform a 90 degree twist should be undertaken over a distance greater that two wavelengths of the frequency used. Image from: https://www.etlsystem s.com/catalogue/rf- components/wavegui de/waveguide- twists/wg17/wr75/r12 0-ku-band- waveguide-90- degree-twists UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION WAVEGUIDE TEE a 3-port device that can be used to either divide or combine two or more signals in a waveguide system. It is formed when three waveguides tubes are connected in the form of the English alphabet 'T'. This is where its name is derived from Main types of Waveguide Tees are : a.) E-Plane Waveguide Tee b.) H-Plane Waveguide Tee c.) Hybrid Waveguide Tee..E-Plane Waveguide Tee.H-Plane Waveguide Tee Hybrid tee is a combination of E-plane and H-plane tee Image from: https://www.everythingrf.com/communit y/what-is-a-waveguide-tee UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION 1. E-Plane Waveguide Tee. When the 2. H-Plane Waveguide Tee. When the axis of the side arm is parallel to the axis of the side arm of the waveguide tee Electric Field (E) of the collinear, then is parallel to the flow of the Magnetic Field the tee is called a E-Plane Tee (H) and is perpendicular to the flow of the Junction. The outputs we get in this Electric Field (E), then the tee is called a type of tee are 180° out of phase with H-Plane Waveguide Tee. An H-Plane each other, irrespective of from which Waveguide Tees can be thought of as a port the input is fed. two way in-phase power divider/combiner i.e it is additive in nature Image from: https://www.everythingrf.com/co mmunity/what-is-a-waveguide- tee UNIT 1 – Module 2 ECE EL 11 MICROWAVE TRANSMISSION Is a two-port device that transmits microwave signals or radio ISOLATOR frequency power in one direction only. Due to internal behavior, the propagation in one direction is allowed while the other direction is blocked. A circulator is a ferrite device (ferrite is a class of materials with CIRCULATOR strange magnetic properties) with usually three ports. The beautiful thing about circulators is that they are non-reciprocal. That is, energy into port 1 predominantly exits port 2, energy into port 2 exits port 3, and energy into port 3 exits port 1. Isolator Image from: http://www.dolphmicrowa Image from: ve.com/product/waveguid Circulator https://www.everythingrf.chttps://www.microwaves101.com/ency e-isolators/ clopedias/circulatorsom/community/what-is-a-waveguide-tee UNIT 1 – Module 2 ECE EL 11 ANTENNA TOWER Tower or masts means any structure designed primarily for the purpose of supporting one or more antennas used for transmitting or receiving analog, digital, microwave, cellular, telephone, personal wireless service or similar forms of electronic communication, In engineering terms, a tower is a self-supporting structure while a mast in supported by stays or guys. UNIT 1 – Module 2 ECE EL 11 ANTENNA TOWER This section presents the three most common types of towers/masts that are used today in wireless communication: (a) self supporting tower, (b) monopole and (c) guyed mast. Image from http://www.itrainonline.org/itrainonline/mmtk/wireless_en/11_Communication_Tower/11_en_mmtk_wireless_co mmunication-tower_handout.pdf UNIT 1 – Module 2 ECE EL 11 ANTENNA TOWER MONOPOLE TOWERS Monopoles are hollow tapered poles made of galvanized steel They are constructed of slip jointed weldedtubes and can be up to 200 feet (60m). Monopoles are primarily used in urban environments where there is limited space available. With a footprint less than 50 sq, m , monopoles are perfect for cities. Other distinguishing advantages include: easy assembly, less expensive installation, interior routing of cables which reduces wind loading, can be deigned for multiple cariiers plus microwave capability, platforms and antenna arrays can be rotated to any azimuth. Image from: https://telehouse- eng.com/product/telecommunication-tower/pole-monopole UNIT 1 – Module 2 ECE EL 11 ANTENNA TOWER SELF SUPPORT TOWERS A self supporting tower (freestanding tower) is constructed without guy wires. Self supporting towers have a larger footprint than monopoles, but still requires a much smaller area than guyed masts. Self supporting tower is the most popular and versatile type of structure used today in the wireless industry. Self supporting towers can be built with three or four sided structures. The wider the base of the tower is, the larger antenna load is acceptable. 3 legged triangular base pattern are the most common. Image from: https://www.indiamart.com/proddetail/self- supporting-tower-4909725262.html UNIT 1 – Module 2 ECE EL 11 ANTENNA TOWER GUYED MAST A guyed mast is a tall vertical structured secured bu guy wires that are anchored in a set of concrete bases on the ground. A guyed mast consists of identical threesides section (approx. 10 ft (3m) each) that are stacked upon each other. The guys of mast has a large footprint. On the contrary, guyed masts can be higher than nonguyed towers and allow A. OFFICER larger antenna load. A guyed mast is ideal for most communication needs, including wireless Internet, cellular and antenna radio towers. Maximum Height, Most Ground space required, Great loading Capacity & Mainly in Rural area UNIT 1 – Module 2 ECE EL 11 ANTENNA TOWER There are in general four major consideration when selecting the type of tower for your deployment: (1) Antenna load, (2) Tower footprint, (3) Height of tower, and (4) Budget Antenna load The antenna loading capability of a tower depends on the structure of the tower. The more surface area of antennas, coaxial cables, brackets and other equipment mounted on the tower and exposed to the wind, the more robust tower is required. The wind load is proportional to the area of the exposed structure and to the distance from the attachment to the ground.. The average wind speed of the site must also be taken into consideration. The average wind speed depends on where on the earth the site is located, the altitude and type surroundings (rural or city). UNIT 1 – Module 2 ECE EL 11 ANTENNA TOWER Tower footprint. The footprint of a tower is the amount of space on the ground that is required for the installation. Depending on the structure of the tower, it requires more or less space for installation. For tall guyed masts (>100feet, 30m), each guy anchor is typically 10-15m from the base of the mast. For a mast with 3 guy wires per level, that results in a footprint of approx. 90-200m2. Height of tower. If you need a structure that is less than 40 feet, you can in fact eliminate the expense and additional work that is required for guying it. Instead you can bracket mount the tower to a house or garage roof even. As mentioned earlier, adding guys cables to a structure will allow higher height UNIT 1 – Module 2 ECE EL 11 ANTENNA TOWER Budget. A general rule of thumb is: “The smaller the tower base, the more costly to purchase and install the tower” Monopoles have the smallest footprint of all towers, and is hence the most expensive type of tower to install. It is followed by self supported towers and then guyed masts which require the largest footprints. Additionally, depending on the tower type you choose, certain tools, machinery and cranes are needed to assemble the tower which must be taken into consideration in the final budget. UNIT 1 – Module 2 ECE EL 11 DISCLAIMER Contents of these modules were taken directly from the references and are owned by the respective authors. No copyright infringement intended UNIT 1 – Module 2 ECE EL 11 REFERENCES Book(s): Tomasi, Wayne. Advanced Electronic Communications Systems, 6th ed., (2014) Frenzel, Louise Jr. E. Principles of Electronic Communication System, 4th ed., (2016) Blake, Roy. Electronic Communication Systems, 2nd ed., (2008) Other Materials: Rule, Manuel T. , Fundamentals on Microwave Communication with Microwave Planning Guide, (2000) http://www.itrainonline.org/itrainonline/mmtk/wireless_en/11_Communication_Tower /11_en_mmtk_wireless_communication-tower_handout.pdf MICROWAVE COMMUNICATION BASICS: THE THEORY, PRACTICES AND TECHNOLOGIES THAT LINK THE WIRELESS WORLD. https://www.commscope.com/resources/eBooks/ UNIT 1 – Module 2 ECE EL 11