WIRELESS AFRICA COPPER EAGLE TRADING 583 (PTY) LTD T/A WIRELESS AFRICA Distributed Antenna System Management Company of South Africa Product Brochure
Defining the Wireless Industry Hosting Technology The traditional way of sending a signal has been the erection of masts (Towers) onto which frequency generating equipment is attached. Masts are common site throughout South Africa. In an attempt to conceal these unattractive objects, service providers have embarked upon creative ways to hide masts from the public eye. We have all seen masts curtained by synthetic trees and the likes. How we use the internet, our mobile phones or the security tracking systems in our cars is only made possible via a technology infrastructure that supports the application. There are several technology applications that support the wireless industry: Wireless Internet (Wi-Fi) Wi-Max 2G 3G 4G UMTS HSDPA GSM GPS GPRS RF Frequencies Equipment Broadband Mi-Fi Hotspots Push to Talk IPTV Multi Port Antenna Omni Antennas SHP Antennas HF Antennas Ground and Air Technical Antennas MIMO WMTS CCTV Microwave Equipment PCS DCS TDMS CDMA WCDMA AWS IDEN Paging Repeaters Solar Devices Five Spot Global Ready V-Cast UHF & VHF Antenna BRSAWS Antenna Wireless Africa Solution (WAS): A simple solution that is practical and cost effective! Place signal generating equipment in the structure Wireless Africa! Signals have to be generated from an elevated position.
Billboards - The Cost Effective Alternative Options: Service providers have two options concerning the installation of signal generating equipment: Option 1: Traditional mast installation (Towers) Cost of mast from R 75 000.00 to R 350 000.00 Cost of Environmental Impact Assessment = R57 500 Time to obtain EIA approval and build tower = 9 months Option 2: Installing wireless equipment in a Wireless Africa Solution: Cost from R 650.00 - R 7 500.00 per month EIA already obtained Installation is immediate ± 15 000 billboards available nationally and ± 30 000 in SADEC ± 4 250 Buildings Available Nationally ± 5 000 Solar Street Name Poles ± 100 000 Street Poles Available Nationally
Facts: Wireless Africa The Cost Effective Alternative Consider the hard facts: Wireless Africa has secured the rights to ± 15 000 billboards available nationally and ± 30 000 in SADEC, ± 4 250 Buildings Available Nationally, ± 5 000 Solar Street Name Poles and ± 100 000 Street Poles Available Nationally. Lease Agreements have been secured for 5 years with an automatic renewal for a further 5 years. First tier service providers have been identified in the form of: 3.1 Telkom 3.2 MTN 3.3 Vodacom 3.4 Altech Netstar 3.5 Tracker 3.6 i-burst Contracts are in place with the above first tier service providers. There are over 750 second tier service providers that Wireless Africa have identified and we are pursuing them on a daily basis. Wireless Africa offer the only logical cost effective alternative to costly and time consuming erection of masts (Towers). DAS (Distributed Antenna System) Street Poles ± 100 000 DAS (Distributed Antenna System) Buildings ± 4250 WIRELESS AFRICA Copper Eagle Trading 583 (Pty) Ltd AMCSA (Antenna Management Company of South Africa) DAS (Distributed Antenna System) Billboards ± 15 000
What is a Distributed Antenna System? A distributed antenna system (DAS) is a network of spatially separated antenna nodes connected to a common source via a transport medium that provides wireless service within a Passive Versus Active DAS Design The size of the desired coverage area is the key factor in geographic area or structure (see Figure 1). A DAS uses fiber deciding whether a passive or active DAS design is needed. optic cable, coaxial cable, and antennas to enhance public Generally speaking, in smaller coverage areas (under 18 580 safety, cellular, and other signals within a building sq. meter), passive designs are adequate, but in larger areas environment. Hospitals for example find them valuable over because the construction of many hospitals impedes the 18 580 sq. meter, from a coverage, link budget, and cost ability for public safety and cellular signals to penetrate standpoint, it makes more sense to use an active system. the building. For example, a DAS will enable the public A passive DAS, which is less expensive and easier to install, safety signal to be enhanced to a signal strength of -85 uses no amplification (see Figure 2). With no power to dbm, while providing up to 90% coverage in any building amplify the signals, the 18 580 sq meter range is the limit at environment, which is now often a requirement in new which you can achieve the required -85 dbm (five bars) on building construction. the mobile device. An active system uses power to amplify signals and is, of A DAS uses a repeater on top of a building to retrieve course, more expensive and more complicated to install the multiple carrier, PCS and/or public safety signals. A (see Figure 3). When designing a DAS, the existing and repeater is an electronic device that receives a signal and potential construction model and also building materials will retransmits it at a higher level and/or higher power, or dictate the actual design and signal propagation. Thus a site onto the other side of an obstruction, so that the signal survey combined with a signal propagation model will need can cover longer distances. A DAS system then distributes the signals throughout the building through one of two designs: passive or active. Passive DAS systems use a coaxial cable with antennas as end points to distribute the signals. Alternatively, in an active design, the signals can be converted to optical light and carried vertically via fiber optic cable through the building floor plate. In this design the signals are then converted back to RF signals and distributed on each respective floor via a coaxial cable and antenna design. Depending upon the size of the implementation, most DAS systems use either a Bi-Directional Amplifier (BDA)or a Base Transceiver Station (BTS). A BDA is a device used to boost the cell phone reception to the local area by the using of a reception antenna, a signal amplifier and an internal rebroadcast antenna. These are similar to the cellular broadcast towers that network providers use to broadcast signals, but are much smaller, usually intended for use by one building. A BTS is more typically used in areas like an airport or stadium where huge numbers of users might overwhelm a cell site. Figure 1 DONOR (ROOF) ANT BI-DIRECTIONAL AMPLIFIER Figure 3 Outdoor Carrier Public Safety Towers/Sources to be completed. Bi-Directional Amplifiers with Antennas that obtain Cell, PCS, Public Safety Sources. Located on the top of the building. Coaxial cable from Bi-Directional Amplifiers to Main Distribution Frame Basic Interface Unit, where all the signals are combined, filtered, and converted to optical. Typically this BIU is located in the MDF (Main Distribution Frame) of the building. Remote Unit converts the optical signals Into RF. They are then combined, filtered, and distributed via a coaxial infrastructure on the floor plate according to the design model. Wiring Closet on each floor Coaxial Infrastructure terminating to a multifrequency, multi-carrier PCS, Public Safety antenna element. Single-mode fiber is routed vertically through the building to each respective IDF (Intermediate Distribution Frame), on each floor. The amount of fiber depends upon the services. Figure 3. This diagram shows in a simplified format how the signals from the carriers are received by an antenna and amplified in an active DAS. The signals are first filtered and converted to an optical transport, then distributed throughout the building. On each floor the signals are converted back to RF and transmitted via a coaxial cable infrastructure. At the end of this coaxial cable infrastructure, one antenna acts to provide uniform and consistent coverage in a general area of 20,000 square feet. ANTENNA TAPS OR SPLITTERS BASIC RF DISTRIBUTION SYSTEM COMPONENTS COAX CABLES INDOOR ANTENNAS Figure 2 Donor Antenna (Operator A: GSM900, GSM1800, UMTS2100) Donor Antenna (Operator B: GSM900, WiMAX 2.5) Node A multi-band (Operator A+B shared GSM900, GSM1800, UMTS2100, WiMAX2.5 Indoor Omni Antenna Directional Coupler 2-way-Splitter Indoor Flat Antenna 3-way-Splitter
HEALTH & SAFETY: FREQUENTLY ASKED QUESTIONS I. What is a Distributed Antenna System (DAS)? A distributed antenna system, or DAS, is a network of spatially separated antenna sites called nodes connected to a common source that provides wireless service within a geographic area or structure. Antenna Figure 1 Figure 2 DAS antennae are typically installed near the top of light standards or on utility poles (figure 1). The DAS antennae are typically mounted 6-12 meters above the ground. As illustrated in the figure 2, the idea is to split the transmitted signal among several antenna sites, separated in space so as to provide coverage over the same area as a single antenna but with reduced total power and improved reliability. A single antenna radiating at high power (a) is replaced by a group of low-power antennas to cover the same area (b). Some of the other advantages of DAS include the ability to provide service for multiple wireless carriers without the need to have separate antenna sites for each carrier at each location and the ability to place the antennae on existing vertical structures such as light or utility poles. III. Is the RF energy from DAS antennas similar to x ray radiation? No. While x-rays are a form of EME, the energy of x-rays is more than 100 million times higher than the radio waves transmitted by DAS antenna. The interaction of x-rays with tissues is completely different than with RF energy. X-rays contain enough energy to change the chemistry of important biological molecules in cells like proteins and DNA though a process called ionization. RF energy is more than 100 million times weaker than x-rays and does not contain anywhere near enough energy to cause ionization and break chemical bonds. For this reason RF energy is referred to as "non-ionizing" radiation. Other forms of non-ionizing radiation include sources of higher energy than RF such as visible light (approximately 100,000 times higher) and lower energy sources such as Extremely Low Frequency (ELF) radiation produced by power lines. Taken together all these forms of EME make the electromagnetic spectrum (figure 3). DAS Equipment II. What are people exposed to from DAS sites? As explained above, DAS uses a network of sites that can communicate with one another and customers near the sites using radio waves. These radio waves are referred to by a number of different names such as electromagnetic energy (EME), radiofrequency radiation (RFR), radiofrequency (RF) energy, electromagnetic radiation (EMR), microwaves, electromagnetic fields (EMF) and non-ionizing radiation. The term "RF energy" or just "RF" is used in this document to refer to transmitted signals from DASsites. Exposure to RF energy is a fact of everyday life. RF energy is emitted by natural sources like the sun and the earth, and by manmade sources such as AM/FM radio and television broadcasts; cellular telephones and their base stations; baby monitors and paging antennas, just to name a few. IV. Are there government safety standards that regulate what emission levels are safe for the public? The Federal Communications Commission (FCC) established the RF safety exposure standard from recommendations contained in existing international and national RF safety standard setting organizations. The FCC issued these standards in order to address its responsibilities under the National Environmental Policy Act (NEPA) to consider whether its actions will "significantly affect the quality of the human environment. In as far as there was no other standard issued by a federal agency such as the Environmental Protection Agency (EPA), the FCC utilized their rule making procedures to consider which standards should be adopted. The FCC gave special consideration to the recommendations by the federal health agencies because of their special responsibility for protecting the public health and safety. In fact, the maximum permissible exposure (MPE) values in the FCC standard are those recommended by the federal health authorities. The FCC standard incorporates various elements of the existing international and national standards which were chosen because they are widely accepted, scientifically based and technically supportable. V. How do I know the safety standards are safe enough? One way to evaluate any safety standard is to compare the standard to similar standards recommended by scientist in other countries and adopted by their governments. The public safety standard for RF energy used by the FCC is identical to that used in Canada and very similar to the vast majority of other RF safety standards used around the world. In addition, it is important to realize that the FCC maximum allowable public RF exposures are not set at a threshold between safety and known hazard but rather at 50 times below a level that the majority of the scientific community believes may pose a health risk to human populations. Thus, considering that the maximum public exposure from DAS sites are typically less than 1-2% of the standard, the "safety margin" from this threshold of potentially adverse health effects of more than 2,500 times.
VI. Where does the RF energy go when it leaves the antenna? The DAS antennae are typically mounted 6-12 meters above the ground. The DAS antennae are designed to send the vast majority of the RF energy straight out from the antenna, (i.e., parallel with the ground), with only a small fraction of the energy emitted down towards the ground or up towards the sky (figure 4). Figure 4 DAS Antenna VII. How do typical public exposures from DAS sites compare to the limits in the public safety standard? Public exposures from DAS sites are typically less than a few percent of the FCC public RF safety standard. In many cases the exposure are less than 0.1% (1,000 times lower than) or even 0.01% of (10,000 times lower than) the safety standard. Direction of Maximum RF Energy More than 100 times less than Maximum RF Energy More than 1,000 times less than Maximum RF Energy VIII. Why are public RF exposures from DAS antennae so low? As previously stated, DAS uses many distributed low power sites to complete it s communications network rather than a single or even a few high power sites to cover the same area. Thus, unlike common broadcast facilities such as AM radio that may have broadcast power as high as 50,000 watts, DAS sites typically use less than 60 watts to transmit their signal. In addition to the fact that the only a small fraction of the antenna s energy is emitted down towards the ground, the intensity of the RF energy decreases very rapidly with distance from the antenna. For example if the exposure at 30m from the site was 2.0% of the safety standard then the exposure 10 times further away (i.e., 304m) would be 100 times less or 0.02% of the standard. At 3048m away the exposure would be 0.0002% or 500,000 (one-half million) times lower than the public safety standard. This rapid decrease in intensity with distance applies to all forms of electromagnetic energy including light (figure 5). Antenna 2% 0.02% Percent of Public Safety Standard 0.0002% Distance from DAS Antenna (feet) 100 1,000 10,000 IX. What are some other common sources of RF energy that the public is exposed to and what are the typical exposures? There are many common cources of public exposure to RF energy such as TV, AM/FM and amateur radio broadcasts; communication devices such as two-way radio, cordless and cellular telephones and Bluetooth headsets; one way communication devices such as baby monitors; household appliances like the microwave oven, and many others. Public exposure from these sources ranges from a very low exposures that are a small percentage of the FCC public exposure standard (e.g., DAS nodes) to much higher exposure that are close to 100% of the public exposure standard (e.g., cell phones). Several examples of typical exposures from various RF sources are shown in figure 6. X. Does exposure to radio waves from DAS cause cancer or other adverse health effects? Responding to similar questions from the public and governments around the world about the potential for adverse health affects from wireless base stations like cellular telephone and DAS sites, the World Health Organization (WHO) released a fact sheet (# 304) in May 2006 which said: "From all evidence accumulated so far, no adverse short- or long-term health effects have been shown to occur from the RF signals produced by base stations. This statement refers to continuous exposures at or below the maximum public safety limits. Specifically in relation to any cancer risk associated with emissions from these types of wireless facilities, the World Health Organization says: Over the past 15 years, studies examining a potential relationship between RF transmitters and cancer have been published. These studies have not provided evidence that RF exposure from the transmitters increases the risk of cancer. Likewise, long-term minimal studies have not established an increased risk of cancer from exposure to RF fields, even at levels that are much higher than produced by base stations and wireless networks." Exposure in Microwatts / cm 2 Cordless Bluetooth Phone Headset CB Mobile Radio Outside Microwave Oven WiFi Laptop Baby Typical Max. Monitor Public Exposure from a DAS Transmission Site Typical DAS Public Exposure in Neighborhood
DAS Solution Typical Outdoor DAS Installation 1. The user s FR signal is received by the antenna on the node. 2. The signal is transmitted via the coaxial cable to the node s equipment box, which contains the amplifier and RF to light converter. 3. The fiber optic cable connects from the equipment box (either underground or aerial) to the hub. 4. The head-end equipment at the hub site converts optical back to RF and send the RF signal through the coaxial cable to the service provider s BTS. 5. Calls are then routed through the service provider s Public Switched Telephone Network (PSTN) and transmitted via the landline network or back out through the DAS equipment. Remote Location - Node Antenna Fiber Optic Cable Coaxial Cable Equipment Box Power Meter Hub Location contains Equipment Room
Contact Us: P. O. Box 12382 Centurion 0046 Tel: +27 (12) 643 0225 Fax: +27 (12) 643 1087 Email: wireless@telkomsa.net Web: www.wirelessafrica.co.za Jan Steyn: +27 (83) 281 1884 jan@pro-tect.co.za Adriaan Stander:082 821 1770 wireless_africa@yahoo.co.uk st Physical Address: Linèl Building, 1 Floor, Office No 6, 2022 Lenchen South Avenue, Centurion, South Africa Wireless Africa