© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— © 2003, Cisco Systems, Inc. All rights reserved.

FWL 1.0—7-2 Module 7 Antennas

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-3 Overview This module will cover basic antenna theory, including directional and omni directional antenna selection. After discussing antenna theory and types of antennas, cables, connectors and accessories for antennas will be discussed. Additionally, important antenna design considerations, such as link engineering, path planning, and installation are also discussed.

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-4 Learning Objectives Define how an antenna is used to propagate an RF signal. Define basic facts of EIRP. Define facts on FCC regulations for UNII-1, UNII- 2 and UNII-3. Identify what an isotropic antenna is and why it is used as a reference for other antennas. Identify Cisco Aironet antennas, their coverage patterns, and the proper polarization of each antenna.

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-5 Key terms Lobes Directional Omnidirectional Beamwidth and Bandwidth Polarization Vertical Horizontal Diversity Plane (H and E) Fresnel Zone

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-6 Definition of Terms dB- Decibel- Ratio of one value to another dBx where x = m = compared to 1 milliwatt (0 dBm=1 mW) i = compare to isotropic antenna d = compared to dipole antenna w = compared to 1 watt (0 dBw = 1 watt)

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-7 Antennas

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-8 Important Antenna Concepts

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-9 Beamwidth

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-10 Cisco Aironet b Antennas FCC requires that ALL antennas sold by a spread spectrum vendor be certified with the radio they are to be sold with All Cisco Aironet b supplied cables, RF devices and antennas have reverse polarity TNC (RP-TNC) connectors Cisco Aironet supplied antennas meet all FCC rules Wide variety of b antennas for most applications

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-11 Cisco Aironet a Antennas FCC requires that all radios utilizing the UNII-1 Band (5.15 GHz – 5.25 GHz) must have non- removable or integrated antennas FCC allows radios utilizing the UNII-2 Band (5.25 GHz – 5.35 GHz) to have external or removable antennas The Cisco Aironet a radios utilize both UNII- 1 and UNII-2 bands, therefore cannot have external or removable antennas Cisco a antennas are integrated into the radio module Cisco 1400 radios utilize UNII-3 bands, therefore have external or removable antennas

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-12 Antenna Concepts Directionality Omni (360º coverage) directional Directional (limited range of coverage) Gain Measured in dBi and dBd (0 dBd = 2.14 dBi) More gain means more coverage - in certain directions Polarization Antennas are used in the vertical polarization

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-13 Antenna Issues (cont.) Antennas have gain in particular directions Direction other than the main intended radiation pattern, are typically related to the main lobe gain

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-14 Antenna Gain If the gain of an antenna goes up, the coverage area or angle goes down Coverage areas or radiation patterns are measured in degrees Angles are referred to as beamwidth Horizontal measurement Vertical measurement

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-15 Beamwidth vs. Gain

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-16 Antenna Theory A theoretical isotropic antenna has a perfect 360º vertical and horizontal beamwidth This is a reference for ALL antennas

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-17 Antenna Theory- Dipole Energy lobes are ‘pushed in’ from the top and bottom Higher gain Smaller vertical beamwidth Larger horizontal lobe Typical dipole pattern

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-18 High Gain Omni-Directionals More coverage area in a circular pattern Energy level directly above or below the antenna will become lower

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-19 Directional Antennas Lobes are pushed in a certain direction, causing the energy to be condensed in a particular area Very little energy is in the back side of a directional antenna Side View (Vertical Pattern) Top View (Horizontal Pattern)

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-20 FCC Part 15 Antenna Requirements b antenna Must use a unique, or proprietary connector Cisco Aironet products use RP-TNC connector Part 15 standards Approved antenna may exceed Exceeding may lead to interference problems Penalties could result in fines FCC standards apply to Part 15 users in the United States Different countries will have similar standards

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz EIRP Rules for FCC Governed Areas Point-to-Multipoint FCC allows increasing the gain of an antenna/cable system if the transmitter power is reduced below 30 dBm in a 1:1 ratio Reduce Transmit Power below maximum of 30 dBm by 1 dBm and increase antenna/cable system gain by 1dBi Point-to-Point Maximum of 36 dBm EIRP Installations – 30 dBm maximum transmitter power with 6 dBi in gain attributed to antenna and cable combination FCC allows exceeding the 36 dBm EIRP in Point-to- Point installations using the 3:1 rule Reduce Transmit Power below maximum of 30 dBm by 1 dBm and increase antenna/cable system gain by 3 dBi

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz EIRP Rules for FCC Governed Areas (cont.) Transmitter Power EIRP Cisco Maximum 6 dBi 36 dBm 100 mW 20 dBm FCC Maximum Maximum Gain Transmitter dBm 1 Watt Point-to-Multipoint 30 dBm 16 dBi 36 dBm Transmitter Power EIRP Cisco Maximum 6 dBi 36 dBm 100 mW 20 dBm FCC Maximum Maximum Gain Transmitter dBm 1 Watt Point-to-Point 30 dBm 36 dBi 56 dBm The above values reflect the 1:1 rule The above values reflect the 3:1 rule

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz EIRP Rules for ETSI Governed Countries Currently ETSI stipulates a maximum of 20 dBm EIRP on Point-to-Multipoint and Point- to-Point installations –17 dBm maximum transmitter power with 3 dBi in gain attributed to antenna and cable combination Professional installers are allowed to increase the gain of an antenna/cable system if the transmitter power is reduced below 17 dBm in a 1:1 ratio Reduce Transmit Power below maximum of 17 dBm by 1 dBm and increase antenna/cable system gain by 1 dBi

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz EIRP Rules for non-FCC Governed Bodies Transmitter Power EIRP Cisco Integrated Antennas 3 dBi 20 dBm Reduced TX Power 30 mW 5 dBi 15 dBm 50 mW 17 dBm 7 dBi 13 dBm 20 dBi 13 dBi 20 dBm Gov. Body Maximum Maximum Gain Transmitter dBm Reduced TX Power 50 mW 20 mW 5 mW 1 mW Point-to-Multipoint and Point-to-Point 17 dBm 7 dBm 0 dBm 2.2 dBi 19.2 dBm 20 dBm The above values reflect the 1:1 rule Governing bodies with 20 dBm ceiling on EIRP: ETSI, France/Singapore, Israel, Mexico

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— a and FCC 5 GHz Specifications FCC regulations for UNII-1 and UNII-2 UNII-1 –FCC max 50 mW –802.11a max 40 mW With max 6 dBi antenna gain –802.11a max of 40 mW complies with all countries except Singapore (20 mW) UNII-2 –FCC max 250 mW –802.11a max 200 mW

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-26 FCC Rules for a - Antennas FCC requires that all radios utilizing the UNII-1 Band (5.15 GHz – 5.25 GHz) must have non- removable or integrated antennas FCC allows radios utilizing the UNII-2 Band (5.25 GHz – 5.35 GHz) to have external or removable antennas FCC requires radios operating in both UNII-1 and UNII-2 bands must comply with antenna rules regulating UNII-1 band (including indoor use only) The Cisco Aironet a radios utilize both UNII-1 and UNII-2 bands, therefore cannot have external or removable antennas and must be used indoors only Cisco a antennas are integrated into the radio module

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-27 Omni directional Antennas

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Omni-Directional Antennas 2 dBi Dipole "Standard Rubber Duck"

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Omni-Directional Antennas 5.2 dBi Mast Mount Vertical

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Omni-Directional Antennas 5.2 dBi Ceiling Mount

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Omni-Directional Antennas 5.2 dBi Pillar Mount Diversity

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Diversity Omni-Directional Antennas 2 dBi Diversity Omni-Directional Ceiling Mount

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Omni-Directional Antennas 12 dBi Omni-Directional (Outdoor only)

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Omni-Directional Antennas 9 dBi omni (Vertical polarization)

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Integrated Antenna Innovative 5 GHz Combo Antenna: Wall Mount: Fold antenna flat against access point housing for 6 dBi gain patch antenna Ceiling Mount: Fold antenna out at a 90° angle for 5 dBi gain omni antenna In 5 dBi omni position In 6 dBi patch position

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-36 Mini-PCI Radio 2.2 dBi Omni-Directional Diversity Antennas Option 1: b Cisco Aironet 1100 Series Internal View

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-37 Cisco Aironet 1100 Series Antenna Details Cone of reduced coverage Sphere of influence Cone of reduced coverage

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-38 H-Plane Pattern E-Plane Pattern Top ViewSide View Floor Cisco Aironet 1100 Series Antenna Details (cont.)

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-39 Directional Antennas

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Diversity Antennas 6.5 dBi Diversity Patch Wall Mount – 55 degree

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Directional Antennas (cont.) 6 dBi Patch Antenna – 65 degree

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Directional Antennas (cont.) 8.5 dBi Patch Antenna – 60 degree

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Directional Antennas (cont.) 13.5 dBi Yagi Antenna – 25 degree

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— dBi Yagi Antenna—Inside view

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Directional Antennas (cont.) 21 dBi Parabolic Dish Antenna – 12 degree

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Omni-Directional Antennas 28 dBi dish (H or V polarization)

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Antenna 9.5 dBi sector (H or V polarization)

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-48 Cable and Accessories

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— GHz Accessories

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-50 RP-TNC Connectors

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-51 Lightning Arrestor Designed to protect LAN devices from static electricity and lightning surges that travel on coax transmission lines RP-TNC connectors used on all Cisco Antennas To Antenna Ground Wire From RF Device Lug Lockwasher Nut

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-52 Lightning Arrestor

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-53 Coax Connection Sealing Number one problems with bridges - water in the connectors Proper sealing is important Coax Seal is one product that is inexpensive and works great

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— Accessories Antenna Alignment Assistance with status/alignment LEDs and RSSI port on outdoor unit Quick-hang mounting bracket supports weight of radio during installation process Complete solution provided with radio including: Power Injector LR Multi Function Mount 20’ and 50’ length of dual RG-6 cable Power supply and cord Coaxial sealant for all exposed connectors Corrosion proof gel for exposed metal surfaces Management via SNMP, Telnet CLI, HTTP Based upon a technology

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0— Power Injector LR Converts standard 10/100 baseT Ethernet RJ-45 interface to F-Type connector dual coaxial cable Power provided over dual coaxial cable with power discovery to protect other appliances Support for longer cable runs by resetting the 100 meter, 100baseT Ethernet timer, enabling total cable runs of 200 meters. Surge protection provided at the F-Type connectors to protect infrastructure devices

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-56 Link Engineering and RF Path Planning

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-57 Path Considerations Radio line of sight Earth bulge Fresnel zone Antenna and cabling Data rate

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-58 Line of Sight The following obstructions might obscure a visual link: Topographic features, such as mountains Curvature of the Earth Buildings and other man-made objects Trees

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-59 Longer Distances Line of Sight disappears at 6 miles (9.7 Km) due to the earth curve

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-60 Fresnel Zone

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-61 Improving Fresnel Effect Raise the antenna New structure Existing structure Different mounting point Remove trees

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-62 Total Distance 60% (Value “F”) Earth Curvature (Value “C”) Antenna Height (Value “H”) Site to Site Fresnel Zone Antenna Height Fresnel zone consideration Line-of-Sight over 25 miles (40 Km) hard to implement

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-63 Antenna Alignment Line of Sight

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-64 Antenna Issues No Downtilt One-way communications High gain omni-directional Directional antenna

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-65 Antenna Issues (cont.) 8 Miles/13 Km 700 ft./213 m downtilt ft./61 m

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-66 Antenna Issues (cont.) Omni-directional antennas provide coverage Also accepts interference from all directions

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-67 Antenna Installation

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-68 Antenna Mounting

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-69 Mounting (Cont.)

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-70 Interference Carrier Detect Test (Spectrum Analyzer) Built into Bridge Run from Console Menu

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-71 Antenna Installation Towers and antennas may require permits and must meet local regulations

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-72 Antenna Installation (cont.) Antenna Alignment Tool Id Name Address Signal Strength Signal Quality 18 Cisco Bridge # fd35 100% -10 dBm 100% 17 Cisco Bridge # fd35 100% -10 dBm 100% 16 Cisco Bridge # fd35 45% -73 dBm 100% 15 Cisco Bridge # fd35 38% -77 dBm 100% 14 Cisco Bridge # fd35 100% -10 dBm 100% 13 Cisco Bridge # fd35 58% -67 dBm 100% 12 Cisco Bridge # fd35 38% -77 dBm 88% 11 Cisco Bridge # fd35 63% -64 dBm 100% 10 Cisco Bridge # fd35 100% -10 dBm 96% 9 Cisco Bridge # fd35 45% -73 dBm 91%

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-73 Antenna Installation (cont.) Aironet Client Utility Site Survey Utility for antenna alignment

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-74 Ladder Safety

© 2003, Cisco Systems, Inc. All rights reserved. FWL 1.0—7-75 Summary Identify characteristics of Cisco Aironet a antennas. Identify characteristics of Cisco Aironet b antennas.

76 © 2003, Cisco Systems, Inc. All rights reserved.