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WiFi Spectrum Analyzer for V300 series. Rev. A02. WiFi Spectrum Analyzer. Test Applications. What can the WiFi analyzer do? Portable spectrum analyzer on a USB dongle that displays all RF activity in the WiFi bands Wireless networks, cordless phones, microwave ovens, Bluetooth devices etc.
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WiFi Spectrum Analyzer Test Applications • What can the WiFi analyzer do? • Portable spectrum analyzer on a USB dongle that displays all RF activity in the WiFi bands • Wireless networks, cordless phones, microwave ovens, Bluetooth devices etc. • Helps determine the best available WLAN channels quickly for optimal performance • Helps to visualize and locate RF signals in the 2.4GHz and 5GHz spectrums • Discover and remedy competing access points • Optimize WLAN networks by locating and eliminating interference sources • Target customers • Wireless IT Consultants and Professionals • A/V and Automation Installers • SMB IT Departments Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer Working Components V300 tester equipped with WiFi SA software option VeEX WiFi SA USB dongle Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer Specifications • Supports 802.11a/b/g/n networks • Supports both 2.4 GHz and 5 GHz bands • Equipped with RP-SMA antenna jack • Allows user to replace standard external Omni-directional antenna with a higher gain or directional antenna as needed. Confidential & Proprietary Information of VeEX Inc.
V300 series – IP Tools Advanced Tools • The WiFi Analyzer is a compact and portable USB dongle that plugs into the USB 2.0 port of the V300 series • The WiFi SA test application menu is located in the Tools/Advanced Tools menu Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer Display Summary • Planar view • Reports current, average, and maximum signal amplitude for each wireless frequency • Topographic view • emphasizes which frequencies are the busiest across the entire spectrum • Spectral view • historical view of wireless spectrum use at a point in time Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer Planar View • Planar View • Traditional Spectrum Analyzer view with Max, Average and Current results • Displays RF activity in real time and tracks average and max values over a given period Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer Topographic View • Topographic View • Similar to a density map - plots frequency versus amplitude • Uses a special color scheme to assign colors to frequency amplitude points and to identify how often a particular co-ordinate is recorded • Great resource for identifying devices with very low duty cycles. • Leaving it running will give a good indication of the typical local network conditions. Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer Spectral View • Spectral View • Waterfall type view across the whole band – graphs amplitude levels over time. • Uses color to pick out the relative signal strength at each point in time. • Great tool for troubleshooting intermittent problems, since it highlights devices that are perhaps emitting only short bursts of noise. • For example - discover microwave oven in the kitchen interfering with WLAN. Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer RF Signatures • Signature button • presets are available to identify unknown sources of RF activity (e.g. microwave oven) • Select a device in the sidebar and click the pattern in the Topographic view to identify a device Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer Inspector - setup • Inspector button - Setup • Allows user to measure the frequency of the RF activity or interference of interest • When selected, a prompt and result box appears Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer Inspector - result • Inspector button – Result • Identifies frequency and amplitude at stylus tapping point • Current, Average and Maximum amplitude values provide an indication of level fluctuation over measurement period Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer Frequency Bands • Frequency button • Allows user to select frequency band for testing Confidential & Proprietary Information of VeEX Inc.
Sales Resources WiFi Spectrum Analyzer Confidential & Proprietary Information of VeEX Inc.
802.11 WLAN standard Quick Facts • Original standard • Ratified in 1997 - used the 2.412 to 2.484GHz frequency band • GLOBAL EQUIPMENT INTEROPERABILITY • MEDIUM TO HIGH DATA RATES • APPLICATIONS • Small offices to Industrial Manufacturing campuses • SPREAD SPECTRUM TECHNOLOGY • Limits transmitted power density • Provides a robust solution in a multi-user environment • Frequency band also used by non IT applications: • 2.4GHz ISM band (83.5MHz Bandwidth) • 2.45GHz at the middle of the Wi-Fi spectrum - same frequency as the magnetron inside a microwave oven that warms up your soup Confidential & Proprietary Information of VeEX Inc.
IEEE 802.11 Standard Main variants • 802.11 (Ratified June 1997) • The original version of the standard released in 1997, but is obsolete today • 802.11a (Ratified September 1999) • Uses the same data link layer protocol and frame format as the original standard, but an OFDM based air interface (physical layer). • Operates in the 5 GHz band with a maximum net data rate of 54 Mbit/s, plus error correction code, which yields realistic net achievable throughput in the mid-20 Mbit/s • 802.11b (Ratified September 1999) • Maximum raw data rate of 11 Mbit/s and uses the same media access method defined in the original standard. • 802.11b devices suffer interference from other products operating in the 2.4 GHz band - these include: microwave ovens, Bluetooth devices, baby monitors and cordless telephones. • 802.11g (Ratified June 2003) • Works in 2.4 GHz band, but uses the same OFDM based transmission scheme as 802.11a. • Maximum physical layer bit rate of 54 Mbit/s (exclusive FEC codes), about 22 Mbit/s Average throughput • Hardware is fully backwards compatible with 802.11b hardware • 802.11n (Ratified October 2009) • Improves upon the previous 802.11 standards by adding multiple-input multiple-output antennas (MIMO) • Indoor range improved from 38m to 70m (approximate) Confidential & Proprietary Information of VeEX Inc.
IEEE 802.11 Standard WiFi Generations Confidential & Proprietary Information of VeEX Inc.
IEEE 802.11 Standard Frequency Spectrum • Unlicensed operation governed by FCC Document 15.247, Part 15 • Spread Spectrum allowed to minimize interference • Uses mostly 2.4GHz ISM (Industrial, Scientific and Medical) band • More Bandwidth to Support Higher Data Rates and Number of Channels • Available worldwide • Good balance of equipment performance and cost compared with 5.725GHz band 902 to 928MHz 2.400 to 2.4835GHz 5.725 to 5.850GHz 26MHz 83.5MHz 125MHz 1 2 3 4 5 6 FREQUENCY (GHz) Confidential & Proprietary Information of VeEX Inc.
IEEE 802.11 Standard Spread Spectrum • Definition: • Spread Spectrum (SS) is a means of transmission whereby: • The transmitted signal occupies a bandwidth much greater than the minimum necessary to send the information • Signal spreading is accomplished by a ‘code’ signal, which is independent of the data • At the receiver, de-spreading is performed by correlating the received SS signal with a synchronized replica of the spread signal • Advantages: • Resists intentional and non-intentional interference • Has the ability to eliminate or alleviate the effect of multipath interference • Can share the same frequency band (overlay) with other users • Privacy due to the pseudo random code sequence (code division multiplexing) • Disadvantages: • Bandwidth inefficient • Implementation is somewhat more complex Confidential & Proprietary Information of VeEX Inc.
IEEE 802.11 Standard Frequency Allocations • The 2.4GHz radio band is split into a number of fixed-frequency channels: • There are 13 usable channels • Channel 1 starts at 2.412GHz • Channels are spaced in 5MHz increments • Channels are 20MHz wide so there’s considerable overlap between them • 40MHz wide channels exist in some 802.11n and speed-boosted versions of 802.11g • Due to this overlap, only three channels can be active at any one time • In practice users and manufacturers tend to choose channels 1, 6 and 11 (USA) • Channel 13 is at 2.472GHz • Channel 14 sits at 12MHz above channel 13 (only legal for use in Japan) • Channels 12 and 13 are illegal in the USA Confidential & Proprietary Information of VeEX Inc.
f5 f4 f3 f2 f1 1 2 3 4 5 6 7 8 9 10 11 12 TIME IEEE 802.11 Standard Frequency Hopping • Principle of operation • FSK data modulation • Periodic changes in the carrier frequency spreads the signal • Carrier frequency changes at a specified hop rate • Carrier frequency hops after a prescribed time • Total system bandwidth includes all of the channel frequencies used in hopping AMPLITUDE FREQUENCY Confidential & Proprietary Information of VeEX Inc.
IEEE 802.11 Standard Protocol Layer Media Access Control Layer PROTOCOL AND PHYSICAL LAYER MANAGEMENT MAC-PHY Sub-layers CONFIGURE DATA FRAMES AND PREAMBLES FOR TRANSMIT AND RECEIVE MODE Physical Layer (PHY) RADIO TRANSMISSION MEDIA FOR EITHER DSSS, FHSS OR INFRARED Confidential & Proprietary Information of VeEX Inc.
WiFi Spectrum Analyzer Sales Arguments • Free Tools available to analyze WLAN issues: • Netstumbler • Wireshark • InSSider • Simply scans for valid Wi-Fi signals across the legal channel slots, but ignores all spurious radiation that affects other devices • Limitations of free tools: • Typically show information about WiFi traffic only, however blind to physical RF issues • RF physical issues are often responsible for WLAN outages Confidential & Proprietary Information of VeEX Inc.
Thank you. Any questions? Confidential & Proprietary Information of VeEX Inc.