Whi h Wi l Wh ? Which Wireless Where? Applying wireless from the rooftop to the desktop Presented by Ernest Schirmer Di t T h l C lti Director, T echnology Consulting Acentech, Inc. Architectural Acoustics Str ct ral D namics Structural Dynamics Environmental Noise Video-Teleconferencing Telecommunications Systems Audio Visual and Sound Systems Audio-Visual and Sound Systems Voice, Data and Multimedia Infrastructure 8 Interplex Dr. Ste 218 Trevose, PA 19053 215-245-8244 [email protected]
99
Embed
Whi h Wi l Wh ?Which Wireless Where? - BICSI Wireless Where.pdfWhi h Wi l Wh ?Which Wireless Where? ... –802.20 Mobil Broadband Wireless Access ... –Standard: IEEE 802.15.1
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Whi h Wi l Wh ?Which Wireless Where?Applying wireless from the rooftop to the desktop
Presented by Ernest SchirmerDi t T h l C ltiDirector, Technology ConsultingAcentech, Inc.
Architectural AcousticsStr ct ral D namicsStructural DynamicsEnvironmental NoiseVideo-TeleconferencingTelecommunications SystemsAudio Visual and Sound SystemsAudio-Visual and Sound SystemsVoice, Data and Multimedia Infrastructure
8 Interplex Dr. Ste 218 Trevose, PA 19053215-245-8244 [email protected]
Which Wireless Where?Applying wireless from the rooftop to the desktop
• Agenda
•Frequency allocation
• Types of wireless connectivity
• The 802 alphabet soup
• Near-field magneticNear field magnetic
• Zigbee
Bluetooth• Bluetooth
• Ultra-wideband
• WiFi
Which Wireless Where?Applying wireless from the rooftop to the desktop
• Agenda (continued)
• Infrared wireless
•WiMAX
• Microwave and laser technology
• General design considerations• General design considerations
• Survey tools
• WLAN antennae
• Mesh networks
• Power-over-Ethernet
Which Wireless Where?Applying wireless from the rooftop to the desktop
• Agenda (continued)
• Cellular telephone vs. WLAN bandwidth
• WLAN telephonesp
• Emerging technologies
• TriviaTrivia
• To learn more
• Wireless is already the Next Big Thing.
Wireless Technologies: What are they good for?
• Voice: telephony, radio networks.
• Data: wireless local area networks.
• Security: cameras.
• Video: still, full-motion.
• Building automation and control.
• Sensor telemetry.
• Tracking: GPS, RFID.
• Machine-to-Machine (M2M).
Sidebar:Sidebar:Sensor Power Sources
Sidebar:P SPower Sources
Terminology
Frequency: The number of times per second a signal repeats. The term “Hertz” (abbreviated Hz) is used instead of cycles per second to honor the German scientist, Gustav Hertz.the German scientist, Gustav Hertz.
For example, middle “C” on a piano vibrates 256 times per second or 256 Hztimes per second or 256 Hz.
Common Frequency Prefixes: At higher frequencies, prefixes are used to eliminate the
d t it t th ti bneed to write out the entire number.
• Kilo = 1,000 (thousand)Kilo 1,000 (thousand)• Mega = 1,000,000 (million)• Giga = 1,000,000,000 (billion)• Tera = 1,000,000,000,000 (trillion)
Licensed Radio Operations: A frequency or radio service that requires coordination with qother users, the approval of the Federal Communications Commission and the i i f di liissuing of a radio license.
Examples of licensed services:p Commercial AM/FM and TV stations Fire, police and EMS radios Some microwave systems
U li d R di O i A fUnlicensed Radio Operations: A frequency or radio service that does not require a license from the Federal Communicationslicense from the Federal Communications Commission.
Examples of unlicensed services: Microwave ovens Cordless phones Cordless phones Citizen band and Family Radio Service Remote control cars and planes Garage door openers
N h di bNote that some radio systems may be a combination of licensed and unlicensed services.services.
Companies that operate cell phone networks must have an FCC license, but the end-user just buys a phone and starts using itusing it.
In the United States, a pilot no longer needs a radio operator’s license (but must get a license when flying into a foreign country)country).
Unlicensed operations are subject to FCC technical standards and specifications. However, assuming the equipment is operating correctly and meets FCC specifications, there is no protection from interference.
The main subject of this course will be the unlicensed 2.4 GHz Industrial, Scientific, & Medical (ISM) band of frequencies. As the ( )name ISM implies, many different types of equipment are designed to use the same frequencies. Under the right conditions this q gcan lead to interference and poor communications.
Frequency Assignmentsq y g
AM Radio
TV TV TV TVTV TV2/4 5/6
TVFM
TV7/13
C lCommon examples:300 Hz - 4 Kilohertz (KHz)
telephone bandwidthtelephone bandwidth
880 Kilohertz (KHz):AM radio station
101 5 Megahertz (MHz):101.5 Megahertz (MHz):FM radio station
2.4 Gigahertz (GHz):Microwave ovens, WLANs
AM R di 580 t 1610 Kil h t (KH )– AM Radio: 580 to 1610 Kilohertz (KHz)
– Low band VHF TV: 54 - 88 Megahertz (MHz)Low band VHF TV: 54 88 Megahertz (MHz)– (channels 2 to 6)
– FM Radio: 88 - 108 MHz
– Aviation: 108 to 136 MHz
Hi h b d VHF TV 174 t 216 MH– High band VHF TV: 174 to 216 MHz– (channels 7 – 13).
– Unlicensed radio equipment:Baby monitors, cordless phones, CB
2.400-2.483 Gigahertz (GHz)Microwave ovens, amateur radio
5.150-5.350 GHz US)5.725-5.825 GHz (Canada)
– No FCC protection from interference.
Primary Unlicensed Frequency Allocations928MHz902MHz 5.850GHz5.725GHz2.4835GHz2.4000GHz
900MHz 2.4GHz 5.8GHz
Th 2 4 GH b d i th i dThe 2.4 GHz band is authorizedworldwide for unlicensed operations.
Types of Wireless Connectivity
Wireless Networking: Making it Work
Specialized Equipment
Useful Range vs TechnologyUseful Range vs. Technology
• Ultra short-range: Near-Field Magnetic Communications
• Very short-range: Zigbee
• Short-range: Bluetooth, Ultra-Wide Band
• Enterprise: WiFiEnterprise: WiFi
• Metro or Campus: WiMAX
• Point-to-Point: WiFi, microwave, laser
Useful Range vs. Data Rate
The Alphabet Soup of Wireless Networking Standards
–802.1x Extensible Authorization Protocol.– 802.11a 54 Mbps at 5 GHz.– 802.11b 11 Mbps at 2.4 GHz.– 802.11d International freq. coordination– 802.11e Quality of Service.– 802.11f Access Point Interoperability.
802 11 54 M b t 2 4 GH *– 802.11g 54 Mpbs at 2.4 GHz.**802.11b compatible.
– 802.11h Adds frequency and power control to 802.11a.
802 i h d i d i– 802.11i Enhanced security and encryption. Requires “forklift” upgrade if using first-generation equipmentgeneration equipment.– 802.11k Advanced radio resource mgmt.– 802.11n Multiple input/Multiple output802.11n Multiple input/Multiple output (MiMo)
Multiple antennae, 600+ Mbps data rate– 802.11p Automotive 5.9 GHz band for direct short-range communications.
– 802.11r Fast roaming between APs– 802.11s Extended Service Set (Mesh)802. s te ded Se ce Set ( es )– 802.11u Internetworking
– 802.15 Personal Area Networks– 802.16 Broadband wireless local access.
“Last mile” access in competition with telephone and “Last mile” access in competition with telephone and cable service providers.
– 802.20 Mobil Broadband Wireless Access Low latency (< 20 ms) Low latency (< 20 ms). Realtime data rates up to 1 Mbps at 150 MPH Porsche has done field trials of 1 Mbps at 206 MPH.
Ultra Short-range:gNear Field Magnetic
CommunicationsCommunications
– NFMC– Standard: None (Proprietary).
R 4 t 6 f t– Range: 4 to 6 feet.– Data Rate: 384 kilobits/second (typical)– Frequency: 10 – 15 megahertz range.– Power: 100 nanowatts.– Relatively unaffected by conductive (metal)
objects or peopleobjects or people.
The strength of the magnetic field “bubble” decreases at the 6th power with distance compared to radiatedat the 6 power with distance compared to radiated electric fields which decrease at the 2nd power.
– NFMC– Battery life (1 AA cell): 25 hours active use;
3 months on standby.– Current applications: wireless audio and
headsets.headsets.– Chipset manufactured by Aura
Communications.
– Note: NFMC is not the same as NFM. NFM refers to Radio Frequency Identification (RFID) technology.
Very Short-range:Very Short range:Personal Area Networks (PAN)
ZigbeeZigbee
– ZIGBEE– Standard: IEEE 802 15 4Standard: IEEE 802.15.4– Range: 30 to 300 feet– Data Rate: 20 Kbps (868 MHz)p ( )– Data Rate: 40 Kbps (915 MHz)– Data Rate: 250 Kbps (2.4 GHz)– Power: <10 microamps (sleep mode)
– ZIGBEE– Up to 255 nodes per networkUp to 255 nodes per network.– Very low-cost electronics (<$2).– Security was not part of original y p g
specification.– Latest specification includes three levels of
security.– Minimal hardware requirements.
Short-range:Short-range:Personal Area Networks (PAN):
Bl t thBluetooth
– BLUETOOTH– Standard: IEEE 802.15.1– Range: 30 to 300 feet.
D t R t 723 Kil bit / d (Kb )– Data Rate: 723 Kilobits/second (Kbps)– Data Rate: 3 megabits/second (peak).– Power: <100 microamps (sleep mode)Power: <100 microamps (sleep mode).– 79 1 MHz channels.– Up to 7 clients form a piconet. Multiple p p p
piconets can link to form scatternets.
Short-range:gUltra-Wideband
– ULTRA-WIDEBAND– Standard: None* (based on IEEE Sta da d: o e (based o
802.15.3a)– Range: 6 to 30 feet.– Data Rate: 480 Mbps at 6 feet.– Data Rate: 110 Mbps at 30 feet.
– IEEE UWB committee disbanded at meeting in Hawaii January 19, 2006.
Enterprise WiFiEnterprise WiFi
Standard Freq. Typ. Data Rate
Max. Data Rate
802.11a 5 GHz 25 Mbps 54 Mbps
802.11b 2.4 GHz 6.5 Mbps 11 Mbps
802.11g 2.4 GHz 25 Mbps 54 Mpbs
802.11n 2.4 GHz 200 Mbps 540 Mbps5 GHz
p p
• Conservative design assumptions suggest:• 802 11b ~100’ radius for 11 Mbps802.11b 100 radius for 11 Mbps.• 802.11a ~ 50’ radius for 54 Mbps.• 802.11g ~ 50’ radius for 22/54 Mbps.g / p• 802.11n ~ 50’ radius for 100 Mbps.• Building materials and contents affect range.
Infrared Wireless Technologygy
• Historical note: Many wireless networking technologies had an infrared interface, but it g ,is rarely ever implemented.
• Once common on printers and laptops (the little ruby-red window).y )
R 30 il– Range: ~30 miles.– Data Rate: 70 Mbps.– Frequency: 10 – 60 GHz (802.16).– Frequency: 2 – 11 GHz (802.16a).– Power: 20 watts average power (typ).– Designed to support mobile connectivity atDesigned to support mobile connectivity at
speeds up to >60 mph.
Point to Point:Point-to-Point:Microwave & Laser
• Microwave– Range 2 to 30 miles depending on g p g
frequency.2 miles at 30 GHz - 30 miles at 2 GHz
– Multiple channelsMultiple channels.Modular systems add bandwidth as
needed.4 T1 i i l l id4 T1 circuits plus analog video.
– License required, but easily obtained.Frequency coordination eliminates q y
interference.Frequencies relatively easy to get.
– Cost effective at about $30,000 per link, i t ll dinstalled.
– No preventive maintenance.– Subject to signal fade, ice, rain, etc.j g
• Laser– Highest bandwidth available.Multiple T3s to 155 Mbps ATM.Multiple T3s to 155 Mbps ATM.OC-3 (155 Mbps) to OC-48 (2.488 Gbps).
– 1,000 meter range.No license required– No license required.
– Cost effective at about $20,000 per link, installed.
by sunlight, etc.– Also known as Free Space Optical
Networking.Networking.
General Design Considerations
Wi l N t kiWireless Networking
S MA M ACSecur
Mana
Adm
in
Mobil
Anten
Coverrity
ageme
nistra
lity
nnarage
entationn
Design Issues We Have Control Of:Design Issues We Have Control Of:
Suitable frequency or service Suitable frequency or service Coverage (area) Capacity (simultaneous users) Bandwidth (applications)( pp ) Transmitting power (may be regulated) Channel selection Cabling El t i Electric power Signal security Physical security
Design Issues We Don’t Have Control Of:Design Issues We Don t Have Control Of:
Other users (same service or frequency) Other users (same service or frequency) Building construction Signal reflection, deflection, refraction, etc. Rouge users (if no or weak security) Rouge users (if no or weak security) Rouge WLAN access points (if access control not used)
Terminology
D ib l G i (i ) l (d ) fDecibel: Gain (increase) or loss (decrease) of signal strength measured as a ratio against a standard or other reference value.standard or other reference value.The ratio is expressed mathematically as:
dB 10 l (P /P )dB = 10 log10 (P1/P2)Example: log10 (100/10) = 2
10 (2) 20 dB10 (2) = 20 dBCommon (power) dB values to remember are: 3 dB = times 2 increase or 1/2 decrease 3 dB = times 2 increase or 1/2 decrease 6 dB = times 4 increase or 1/4 decrease 20 dB = times 10 increase or 1/10 decrease
Attenuation: Signal loss caused by transmission through a wire, the air, or bj t l t d b t th t itt dobjects located between the transmitter and
the receiver.
Attenuation: Radio signals traveling through free space are attenuated according to a “ l ” f l“square law” formula.
Signal strength = q/r2
Where q = signal source and r = distance from the sourcefrom the source.
double the distance and the signal d b f t f 4 ( 1/4 f it idecreases by a factor of 4 (or 1/4 of its prior value).
Common Building MaterialsAttenuation at 2.4 GHz
( ll l i t )(all values are approximate)
Glass (non-tinted)-2 to -3 dBWood door -3 dBSystems furniture -3 to -5 dBDry wall (sheetrock) -3 to -4 dBDry wall (sheetrock) 3 to 4 dBMarble -5 dBBrick -8 dB to -10 dBC t (fl / ll) 10 t 15 dBConcrete (floor/wall) -10 to -15 dB
Design Issues: Received Signal Strength
P = (P )(G )(G )(l/4πd)2Pr = (Pt)(Gt)(Gr)(l/4πd)2
Where:Pr Received powerr pPt Effective radiated powerGt Antenna gainGr Receiver gainλ wavelength in metersπ pi (3.1415962…..)d distance in meters
Design Issues: Path Loss:Path LossdB = 20 log (4l/π)+10 log (dn)Where:λ l th i tλ wavelength in metersπ pi (3.1415962…..)d distance in metersn = 2.0 free space.2 7 to 3 5 outdoor urban areas2.7 to 3.5 outdoor urban areas.3.0 to 5.0 shadowed outdoor urban areas.1.6 to 1.8 in-building, direct line-of-sight.3 0 t 3 5 i b ildi f b i d3.0 to 3.5 in-building, fabric covered
partitions.4.0 to 6.0 in-building, obstructed, office.2.0 to 3.0 in-building, obstructed,
warehouse.
Design Issues: Link Budget:
Pr = Pt + Gt + Gr – Path loss - Lr
Where:Pr Received powerPt Effective radiated powert pGt Antenna gainGr Receiver gainLR Receiver loss (noise figure)*R ( g )
*A common specification for receiver sensitivity is -93 dB.Th i h i l h i bThat is, the signal at the receiver must be at least -93 dB to be detected.
Typical WLAN
Network Configuration
Sit SSite Survey
For some radio systems a site survey can be For some radio systems a site survey can be done. This involves measuring the signal strength at specific locations or a given distance f t t tfrom a test antenna.
After the survey is completed a contour map is drawn. The lines on the map connect points of equal signal strength just as the lines on a weather map connect points of equal barometricweather map connect points of equal barometric pressure.
Site SurveySite Survey
Although this can be done for a WLAN it is much Although this can be done for a WLAN it is much more common to take a laptop and walk the building to determine where additional access points are needed to obtain reliable coverage in a given area.
(Relatively) Inexpensive Site Survey Tools( y) p y
Wireless Networking Performance
• There can be large differences between the specifications given in a manufacturer’s data sheet and performance in the real worldsheet and performance in the real world.
• Signal-to-noise ratio determines data rate.• Coverage vs. Capacity Planningg p y g
WLAN Antennae
• Rough Rules of Thumb– Doubling the height of an antenna has
approximately the same affect as increasing transmitter power by a factor of 10.
– BUT doubling the height of an antenna or– BUT doubling the height of an antenna or increasing transmitting power by a factor of ten does not double the coverage area. As a
l f th b li bl tirule of thumb, reliable operating range increases by approximately 30%.
Which female Hollywood star invented spread spectrum technology and received patent #2,292,387 on Aug. 11, 1942?(Technology first put into use during the 1962 C b i il i i )Cuban missile crisis)
Hint: Born in AustriaHint: Dropped out of schoolHint: Dropped out of schoolHint: Married six timesHint: Worked with George AntheilgHint: Ms. Hedwig Eva Maria KieslerHint: HL
To Learn More
Newton’s Telecom DictionaryNewton s Telecom DictionaryAuthor: Harry NewtonPublisher: Flatiron Publishing• ISBN 0-979-38733-7
The one to buy if you’re e o e to buy you ebuying only one!
Practical Packet Analysis:Practical Packet Analysis:Using Wireshark to Solve RealWorld Network ProblemsAuthor: Chris SandersPublisher: No Starch PressISBN: 1-593-27149-2ISBN: 1 593 27149 2
The ARRL HandbookAuthor: American Radio
Relay League (ARRL)Relay League (ARRL) Publisher: ARRLISBN: 0-872-59144-1
Electromagnetics ExplainedAuthor: Ron SchmittPublisher: NewnesISBN: 0-750-67403-2ISBN: 0 750 67403 2
www.spiceworks.com
Thank YouErnest SchirmerDi T h l C l iDirector, Technology ConsultingAcentech, Inc.8 I t l D i S it 2188 Interplex Drive, Suite 218Trevose, PA 19053215 245 7125215 - 245 - [email protected] acentech comwww.acentech.com