Pro Audio White Space Finder

Transcription

1 Pr Audi White Space Finder 1 / 48

2 Intrductin Welcme t Pr Audi White Space Finder (PAWS4400) -- a new, PC-based RF spectrum analyzer specifically designed fr the prfessinal wireless audi and vide industries. The new analyzer is the industry's first, PC-based RF spectrum analyzer t ffer spectrum analysis, intermdulatin analysis and autmatic charting f pen white space (pen RF frequency) fr use with wireless micrphnes, in-ear mnitrs, remte cntrl, security, access cntrl, etc -- all built int a single tl. The unique features extend beynd the bunds f traditinal RF analyzers. Thugh Pr Audi White Space Finder is well suited fr wireless prfessinal audi prductin and AV integratin, it is als the perfect tl fr general cmmercial and industrial RF wrk. It supprts frequency ranges 500 KHz thrugh 4400 MHz. Belw are a few f Pr Audi White Space Finder's mre unique features and functins: Intermdulatin Analysis White Space & Intermd-Cmpatible Frequencies Mnitred Frequencies Regin-Of-Interest (ROI) Trace View 3-Dimensinal Waterfall Histry View Tpgraphic Trace View Delta Trace View Easy-t-use Cntrl Panel fr settings adjustments Highly sensitive and stable Signal Hundä RF spectrum analyzer receiver Main View 2 / 48

3 Spectrum Trace View Regin-Of-Interest Trace View 3 / 48

4 Waterfall Histry View Mnitred Frequencies White Spaces and Intermd-Cmpatible Frequencies Tpgraphic Map 4 / 48

5 Delta Trace View Cntrl Panel 5 / 48

6 Signal Hundä is a trademark f Test Equipment Plus. 6 / 48

7 Installatin Suggested System and Hardware Requirements: PC running Windws XP Prfessinal (SP3), Windws Vista, Windws 7 (32- r 64 bit) Micrsft.NET Framewrk versin 3.5 (r later) An available USB prt fr interfacing with the Signal Hundä RF spectrum analyzer CPU: Intel Pentium 4, 1.2 GHz r faster Memry: 2048 MB r greater Hard Drive: 1000 MB free space r greater Vide: 32 MB vide RAM Display reslutin: 1280x1024 r greater Installing and Launching the Pr Audi White Space Finder Applicatin 1) Befre beginning the installatin it will be necessary t dwnlad the latest versin f Pr Audi White Space Finder frm ur website ) Yu will need administrative privileges in rder t install the applicatin sftware n yur cmputer. Please lgin t an accunt n yur cmputer that includes 'Administratr' rights befre prceeding with the installatin. 3) Run the Pr Audi White Space Finder setup prgram and fllw the prmpts fr installing the applicatin. Be sure t review the License Agreement as yu prgress thrugh the installatin prcedure. When the Setup Wizard has cmpleted then click the 'Finish' buttn. By default the applicatin is installed under in the flder '\Prgram Files \RatinalWaves\WhiteSpaceFinder and a desktp icn is created (labeled 'White Space Finder'). 4) Attach the Signal Hund spectrum analyzer t yur PC using the USB-t-PC cnnectin cable that shipped with the prduct. 5) The first time the applicatin is launched yu will be prmpted t register the applicatin. If yu have nt yet purchased a Registratin Cde r if yu d nt have a Signal Hund RF spectrum analyzer then yu can still run the applicatin in 'Dem Mde'. In 'Dem Mde' the applicatin is fully functinal but uses simulated data. If yu d have a Registratin Cde then yu can enter it at this time by selecting 'Enter Registratin Cde'. The Registratin Cde is 20 hexadecimal digits -- i.e. 5 grups f 4 hexadecimal digits separated by hyphens (e.g B62-544A ). When yu enter the Registratin Cde it is nt necessary t include the hyphens. 7 / 48

8 Cntrl Panel When the applicatin first launches, the main charting windw appears alng with the Cntrl Panel. The Cntrl Panel includes imprtant settings and is used t cnfigure the sftware and spectrum analyzer. The settings include: Start / Stp Scan 8 / 48

9 Built-in Prfiles 'Trace Only' mde Scan Settings Default Frequency Set Sensitivity Settings Scan Averaging Scale Settings Start / Stp Scan Pr Audi White Space Finder emplys a wide-band RF spectrum analyzer that scans the frequency range specified by the user. Scanning is cntrlled by the 'Start Scan' and 'Stp Scan' buttns. Scanning repeats cntinuusly until the 'Stp Scan' buttn is pressed. The frequency range that is scanned is defined by the 'Start' and 'End' frequency settings (see belw). Built-in Prfiles The Pr Audi White Space Finder applicatin cmes pre-cnfigured with 'Built-in Prfiles'. These prfiles cntrl many imprtant parameters, including the fllwing: Start and End frequencies, Regin-Of-Interest (ROI), sensitivity, scaling, and the Mnitred Frequencies settings. The applicatin als supprts 'User-defined Prfiles'. When yu select ne f the built-in prfiles frm this drp-dwn list then thse settings are immediately applied thrughut the applicatin and will be in effect the next time the 'Start Scan' buttn is pressed. In general, the built-in prfiles use default settings and differ nly in their Start and End frequencies. As a side nte, the built-in prfiles can nt be accessed while the analyzer is actively scanning. That is, if the analyzer is scanning and yu wish t use a built-in prfile then it is necessary t first press the 'Stp Scan' buttn. Trace Only (mde) 9 / 48

10 On thse ccasins when yu nly wish t capture spectrum traces and are nt interested in perfrming intermdulatin analysis, then yu can save time by selecting the 'Trace Only' checkbx. When 'Trace Only' mde is selected then the Spectrum Trace view expands t full screen and the ther diagnstic charts are nt available. Als, Intermdulatin Analysis is nt available during 'Trace Only' mde. Scan Settings The mst imprtant parameters are the Start and End frequencies, which are set here. The Start and End frequencies can be set explicitly r implicitly, if yu prefer, by setting the Center frequency and the Span. They are always specified in units f megahertz (MHz). Supprted frequencies are 500 KHz thrugh 4400 MHz. As a side nte, the scan settings can nt be accessed while the analyzer is actively scanning. That is, if the analyzer is scanning and yu wish t change the frequency range then it is necessary t first press the 'Stp Scan' buttn. Intermdulatin Frequency Set 10 / 48

11 Intermdulatin interference is rarely desirable in wireless cmmunicatin systems -particularly in radi r audi prcessing. Furthermre, it is nt smething that is readily measurable and avidable (e.g. using an RF spectrum analyzer). Hwever, the physical basis fr IMD is well understd and the mathematical frmulas used t describe it are relatively simple -- s, cmputatinal methds can be applied t generate frequency sets that are free f intermdulatin interference and which mitigate its effect. If yu are interested in learning mre details abut intermdulatin distrtin there are many articles and references available n the Internet. Fr a gd explanatin we refer yu t the fllwing article: Intermdulatin Perfrmance and Measurement f Intermdulatin Cmpnents. A 'Frequency Set' is a set f cmputed frequencies that are related in a very imprtant way -- they are intermdulatin-cmpatible. That is, their intermdulatin prducts d nt interfere with the frequencies in the set. Pr Audi White Space Finder prvides tw ways fr yu t intrduce a Frequency Set that will be applied fr real-time intermdulatin analysis -- 'Aut-generate' and 'Imprt Existing'. Aut-generate: When the 'Start Scan' buttn is pressed then the applicatin will cmpute a frequency set fr the specified frequency range that tests fr tw-transmitter, 3rd-rder intermdulatin prducts (2Tx3rds). This takes nly a few secnds and is perfrmed prir t the first scan. With each scan the 'Whitespaces And Intermd-Cmpatible Frequencies' chart is updated. Taking int accunt bth white space regins and the cmputed frequency set, the chart displays thse channels that are bth free f RF interference and intermdulatin distrtin. These are the channels yu wuld then assign t yur wireless transmitters. Imprt Existing: If yu have previusly created a frequency set using Pr Audi White Space Finder r Intermd Assist and saved it in an XML-frmated file, then yu can imprt that file. In this case, the applicatin takes int accunt the white space regins and the imprted frequency set when cmputing the best channels. Again, with each scan, the 'Whitespaces And Intermd-Cmpatible Frequencies' chart is updated and displays thse channels that are bth free f RF interference and intermdulatin distrtin. White Space Setting The 'White Space Threshld' slider cntrls the threshld signal strength (in dbm) belw which is cnsidered 'White Space'. When yu adjust this cntrl yu'll als see the hrizntal, white line in the Spectrum Trace view mve up and dwn accrdingly. Alng thse frequency spans where the white line is slid and nt interrupted by a peak, then this wuld be cnsidered a White Space regin. It is cmpletely up t the user as t what is an apprpriate threshld fr this cntrl -- it depends greatly n the envirnment yu are wrking in and what level f signal transmissins yu feel can be safely ignred. Thse frequencies whse signal strength amplitudes exceed the threshld are cnsidered ff-limits and are lcked-ut -- that is, they will nt be cnsidered as candidates fr a frequency set. The results frm determining the White Space regins are used fr lcating pen frequency space in crwded RF envirnments and applied t cmputing the best frequencies and spacing fr setting-up multiple transmitters -- as shwn in the 'Whitespaces And IntermdCmpatible Frequencies' view. This is mst helpful when frequency crdinatin and RF interference are factrs that need t be taken int cnsideratin when selecting which frequencies r channels t assign t wireless transmitters. 11 / 48

12 By default, hide Maxima traces Selecting this CheckBx causes the Maxima traces t be hidden by default in the Spectrum and Regin-Of-Interest (ROI) Trace views. The Maxima traces can be re-enabled frm the ppup menu that is accessed by right-clicking n either the Spectrum r ROI Trace views. Save last settings and apply them as the default settings the next time the applicatin is launched When this CheckBx is selected then the next time the applicatin is launched it will remember yur last settings and apply them t the new sessin. Sensitivity Settings We recmmend yu leave the sensitivity settings at their default values: 0 dbm Attenuatin, Reslutin Bandwidth f 25.6 KHz and Preamp enabled. Attenuatin: The internal electrnic attenuatr may be set t 0, 5, 10 r 15 db. A Lcal Oscillatr signal may be bserved at the RF input prt, ften fund 10.7 MHz abve the RF frequency being scanned. Typically, this level will nt interfere with yur measurements. If yu are cnnecting t an antenna and suspect LO feedthrugh is a prblem, then this can be mitigated by setting the attenuatr t 15 db. This will typically reduce yur LO leakage t less than 2 nanwatts fr all frequencies belw 1 GHz -- but at the expense f sensitivity. Reslutin Bandwidth: Reslutin Bandwidth (RBW) cntrls the frequency reslutin f the frequency axis -- that is, the smallest distance that can be reslved between tw adjacent peaks. In FFT-based analyzers (such as the Signal Hund spectrum analyzer) the FFT and its assciated windwing parameters determine the frequency reslutin r reslutin bandwidth. As yu lwer the RBW t imprve frequency reslutin the sweep time increases because the FFT spectrum analyzer is perfrming a lnger data acquisitin and larger FFT calculatin. Preamp: A preamplifier was designed int the Signal Hund spectrum analyzer t reduce the displayed average nise level. 12 / 48

13 Scan Averaging Scan averaging (als referred t as vide averaging) accumulates and averages scans ver time. RF signals can fluctuate quite a bit frm ne scan t anther, and scan averaging helps t eliminate sme f the nise and enhance the pattern f the true signals. One dwnside t using scan averaging is that in an unstable RF envirnment where signals are spntaneusly appearing r disappearing, then these changes culd be slw t appear in the diagnstic views. T disable scan averaging, set the number f scans t average t '0'. Baseline Filter The raw data acquired during a spectrum scan can be very "spikey" -- making it difficult t identify a baseline fr the spectrum trace. By default a baseline filtering algrithm (implemented in sftware) is applied t the raw data. Belw are examples f traces with and withut baseline filtering enabled. 13 / 48

14 Scale Settings Tw types f scaling can be applied t spectrum traces -- autscaling (the default) and manual scaling. When autscaling is selected then manual scaling is disabled. When manual scaling is used, the slider cntrls the lwer and upper bundaries (in dbm) f the Spectrum, ROI, Tpgraphic and White Spaces views. The aut and manual scaling cntrls can be used t "zm" the trace views and enhance their clarity. This has n effect n data acquisitin r intermdulatin analysis -- nly n hw the data is displayed. 14 / 48

15 The 'Waterfall Scale' slider cntrl applies nly t the 'Waterfall Histry' view. This cntrl can be used t rescale and remap the signal strengths t better spread them acrss the range f clrs that are used (see legend t the right f the Waterfall Histry view). This is useful when all the signal strengths are large and the Waterfall view appears mstly red r when all the signal strengths are lw and the Waterfall view appears mstly blue. Fr the best visual effect, ideally yu'd like the peaks (strng signals) t appear red and the valleys (weak signals) t appear blue. But smetimes even the valleys have large signal strength values r the peaks have lw signal strength values. This cntrl is useful in remapping the clr legend t better make use f the clrs and hw they are spread acrss the peaks and valleys f the signal strength values. Spectrum Trace View Pr Audi White Space Finder cntinuusly scans and samples the signal strength (dbm) f frequencies in the range the user has specified. In the 'Spectrum Trace' view the signal strength data (in dbm) is displayed as a functin f frequency. By default 2 traces are displayed -- Current (green) and Maxima (red). The Current trace displays the signal strength data frm the mst recent scan. The Maxima trace displays the maximum signal strength fr each frequency since the scan sessin was begun. 15 / 48

16 In the upper-right-hand crner f the view there is a small rectangle that displays the current [x,y] grid crdinates in MHz and dbm. As yu mve the muse cursr arund the chart then these crdinates are cntinuusly updated. When yu right-click the muse buttn then a ppup menu appears with several chices yu can select frm: Full Screen view Left Buttn used fr creating Marker pints r 'Ht Spts' Left Buttn used fr specifying a Regin-Of-Interest (ROI) Clear Markers and ROI utline frm the display Hide Maxima Trace These chices will be discussed further belw... Full Screen view When yu select 'Full Screen' frm the ppup menu then the Spectrum Trace view will enlarge and fill the entire screen and the tw, lwer display windws will becme minimized. T restre the Spectrum Trace view t its riginal dimensins then again access the ppup menu by right-clicking the muse and this time select 'Restre Screen'. Left Buttn used fr creating Marker pints r 'Ht Spts' 16 / 48

17 When yu select 'Left Buttn: Marker Pints' frm the ppup menu then subsequent leftclicks create Marker pints r 'Ht Spts' that display the crrespnding frequency (in MHz) and signal strength (in dbm) fr the lcatin in the grid that yu just clicked n. Left Buttn used fr specifying a Regin-Of-Interest (ROI) When yu select 'Left Buttn: Regin-Of-Interest frm the ppup menu then by pressing and dragging the left muse buttn yu can utline a Regin-Of-Interest r ROI. When Pr Audi White Space Finder first launches 3 views are displayed -- the middle ne is the 'Regin-Of-Interest (ROI) Trace' view. And it is this view that will shw the trace infrmatin fr the ROI that yu just defined. 17 / 48

18 Clear Markers and ROI utline frm the display If the 'Spectrum Trace' view becmes t cluttered with Markers and the ROI utline, then these can be remved frm the display by selecting 'Clear Markers' frm the ppup menu. Hide Maxima Trace When yu select this ptin frm the ppup menu then the Maxima trace is n lnger displayed. If the Maxima trace is currently hidden and yu wish t display it again, then frm the ppup menu select 'Shw Maxima Trace' and it will nce again be displayed in the view. Regin Of Interest Trace View Pr Audi White Space Finder cntinuusly scans and samples the signal strength (dbm) f frequencies in the range the user has specified. In the 'Regin-Of-Interest (ROI) Trace' view the signal strength data (in dbm) is displayed as a functin f frequency. By default 2 traces are displayed -- Current (green) and Maxima (red). The Current trace displays the signal strength data frm the mst recent scan. The Maxima trace displays the maximum signal strength fr each frequency since the scan sessin was begun. In the upper-right-hand crner f the view there is a small rectangle that displays the current [x,y] grid crdinates in MHz and dbm. As yu mve the muse cursr arund the chart then these crdinates are cntinuusly updated. 18 / 48

19 When yu right-click the muse buttn then a ppup menu appears with several chices yu can select frm: Left Buttn used fr creating Marker pints r 'Ht Spts' Clear Marker frm the display Hide Maxima Trace These chices will be discussed further belw... Left Buttn used fr creating Marker pints r 'Ht Spts' When yu select 'Left Buttn: Marker Pints' frm the ppup menu then subsequent leftclicks create Marker pints r 'Ht Spts' that display the crrespnding frequency (in MHz) and signal strength (in dbm) fr the lcatin in the grid that yu just clicked n. Clear Markers and ROI utline frm the display If the 'Regin-Of-Interest' view becmes t cluttered with Markers, then these can be remved frm the display by selecting 'Clear Markers' frm the ppup menu. Hide Maxima Trace When yu select this ptin frm the ppup menu then the Maxima trace is n lnger displayed. If the Maxima trace is currently hidden and yu wish t display it again, then frm the ppup menu select 'Shw Maxima Trace' and it will nce again be included in the view. 19 / 48

20 Mnitred Frequencies This feature allws yu t mnitr any 20 frequencies within the the frequency range supprted by yur receiver. Furthermre, yu can specify an 'Alert Threshld' -- such that if the signal strength f an interfering transmitter were t rise abve this threshld then the crrespnding bar fr that frequency turns red (therwise it appears green). The purpse f this feature is t alert yu in the event the ambient RF energy, measured at specific frequencies, were t rise abve a threshld value -- thereby psing a risk t using a specific frequency as ne f the channels yu assign t an audi transmitter. 20 / 48

21 T specify the frequencies yu wish t mnitr select Tls / Mnitred Frequencies frm the main menu. The 'Mnitred Frequencies' DialgBx will then appear. Frm here yu can enter up t 20 frequencies t mnitr alng with a shrt descriptin. The shrt descriptin will be used t identify the frequency bar in the Mnitred Frequencies view. Adjacent t each frequency is a check bx -- if a check appears in the check bx then that frequency will be mnitred -- therwise, if unchecked, then it will be ignred. This DialgBx als prvides a slider cntrl fr setting the 'Alert Threshld'. If the signal strength f a mnitred frequency falls belw this threshld then its crrespnding bar will appear red in clr (therwise, it is green). As a side nte, the 'Mnitred Frequencies' DialgBx can nt be accessed while the receiver is actively scanning. That is, if the receiver is scanning and yu wish t change these frequencies then it is necessary t first press the 'Stp Scan' buttn. Waterfall Histry The 'Waterfall Histry view is als knwn as a "heatmap" graph. It is a 3-dimensinal representatin f the data, where the X-axis is the frequency scale, the Y-axis is a time scale, and the "Z-axis" is the clr scale. Each hrizntal line in the Waterfall chart displays the signal strength (as a clr) as a functin f frequency as measured ver the time perid f ne scan. That is, with each scan (r sweep) a new rw is added at the bttm f the Waterfall chart.the clr legend t the right shws that strnger signals will appear red and weaker signals will appear blue. On the Cntrl Panel there is a grup f settings with the heading 'Scale Settings'. Within that grup f settings there is a 'Waterfall Scale' slider cntrl that applies nly t the 'Waterfall Histry' view. This cntrl can be used t rescale the signal strengths t better spread them acrss the range f clrs that are used. This is useful when all the signal strengths are large and the Waterfall appears mstly red r when all the signal 21 / 48

22 strengths are lw and the Waterfall appears mstly blue. Fr the best visual effect, ideally yu'd like the peaks (strng signals) t appear red and the valleys (weak signals) t appear blue. But smetimes even the valleys have large signal strength values r the peaks have lw signal strength values. This cntrl is useful in remapping the clr legend t better make use f the clrs and hw they are spread acrss the peaks and valleys f the signal strength values. Whitespaces And Intermd-Cmpatible Frequencies This is ne f the mre pwerful features f Pr Audi White Space Finder -- it is used fr lcating pen frequency space in crwded RF envirnments PLUS frequency crdinatin -that is, assigning channels that are bth free f RF interference and intermdulatin distrtin. In the Cntrl Panel a user specifies a signal strength t be used as the 'White Space Threshld' -- frequencies that fall belw this threshld are cnsidered pen and available and will be included in the intermdulatin analysis. The 'White Space Threshld' slider cntrls the threshld signal strength (in dbm) belw which is cnsidered 'White Space'. When yu adjust this cntrl yu'll als see the hrizntal, white line in the Spectrum Trace view mve up and dwn accrdingly. Alng thse frequency spans where the white line is slid and nt interrupted by a peak, then this wuld be cnsidered a White Space regin. It is cmpletely up t the user as t what is an apprpriate threshld fr this cntrl -- it depends n the envirnment yu are wrking in and what level f backgrund RF energy yu feel can be safely tlerated. As with mst things, there are trade-ffs. The lwer (mre strict) the threshld, the less white space and fewer intermd-cmpatible channel assignments available. The higher (mre lenient) the threshld, the mre white space and mre intermd-cmpatible channel assignments will be available. The measurements fr White Space regins are used fr lcating pen frequency space in crwded RF envirnments and are applied t the intermdulatin analysis. The cmputed results shw the best channel assignments fr setting-up multiple transmitters -- as shwn in the 'White Spaces and Intermd-Cmpatible Frequencies' view. These channel assignments are free f RF interference and intermdulatin distrtin. This is mst helpful when frequency crdinatin and RF interference are factrs that need t be taken 22 / 48

23 int accunt when selecting which frequencies r channels t use. When yu right-click the muse buttn inside the 'White Spaces and Intermd-Cmpatible Frequencies' chart then a ppup menu appears -- selecting 'Mre Inf...' causes a DialgBx t display that lists all White Spaces and Channel Assignments (Frequency Set) in table frmat. T save the frequency set t a file, frm the main menu select 'File / Create Reprt...'. This allws yu t save the Frequency Set, list f white spaces, and current charts t a PDF file. Tpgraphic Map 23 / 48

24 This chart shws accumulated RF energy as a functin f frequency. The pwer f the signal strength in dbm is shwn acrss the frequency span. A signal strength that appears with a relatively lw ccurrence is 'blueish' in clr, whereas increasingly brighter clrs are used fr signal strengths that ccur mre frequently. Signal strengths that ccur mst ften are 'redish' in clr. Over time, this spectral view will apprximate the steady-state RF energy signature f a given envirnment. Delta Trace View The Delta trace view can be used t view small (r large) changes in the RF spectrum ver time. Here's hw it wrks... When scanning begins the first trace is saved as a 'snapsht'. Fr all subsequent scans, the snapsht trace is subtracted frm the current trace and the difference, i.e. 'delta', is displayed. Pltting the data in this way makes it easy t detect RF changes that ccurred since the initial 'snapsht'. Ppup Menus Ppup menus are assciated with several charts and are displayed by right-clicking n the chart. They prvide access t additinal features, as described belw. 24 / 48

25 The ppup menu assciated with the 'Spectrum Trace' view supprts the fllwing features: Full Screen: When yu select this ptin frm the ppup menu then the 'Spectrum Trace' view will enlarge and fill the entire screen and the tw, lwer display windws will becme minimized. T restre the 'Spectrum Trace' view t its riginal dimensins then again access the ppup menu by right-clicking the muse and this time select 'Restre Screen'. Left Buttn: Marker Pints: When yu select this ptin frm the ppup menu then subsequent left-clicks create Marker pints r 'Ht Spts' that display the crrespnding frequency (in MHz) and signal strength (in dbm) fr the lcatin in the grid that yu just clicked n. Left Buttn: Regin-Of-Interest: When yu select this ptin frm the ppup menu then by pressing and dragging the left muse buttn yu can utline a Regin-Of-Interest r ROI (see belw). When the applicatin first launches 3 views are displayed -- the middle ne is the 'Regin-Of-Interest (ROI) Trace' view. And it is this view that will shw the trace infrmatin fr the ROI yu just specified. Clear Markers: If the 'Spectrum Trace' view becmes t cluttered with Markers and the ROI utline, then these can be remved frm the display by selecting 'Clear Markers' frm the ppup menu. Hide Maxima Trace: When yu select ne f these ptins frm the ppup menu then the Maxima trace is n lnger displayed. If the Maxima trace is currently hidden and yu wish t display it again, then frm the ppup menu select 'Shw Maxima Trace' and it will nce again be included in the view. 25 / 48

26 The ppup menu assciated with the 'White Spaces And Intermd-Cmpatible Frequencies' view supprts the fllwing feature: Mre Inf: When yu select 'Mre Inf' then a table appears that displays a listing f the white space regins and a frequency set with the current channel assignments cmputed frm the last scan. 26 / 48

27 Intermd Settings 27 / 48

28 When perfrming intermdulatin calculatins there are several settings that affect the size and stringency f the resulting frequency set. These include the fllwing: Intermd Stringency / Cmpatibility Level Step Size Ignre Certain Intermd Prducts Intermd Stringency / Cmpatibility Level Pr Audi White Space Finder calculates the 3 types f intermdulatin prducts that happen t be clsest t ur fundamental frequencies. These are: Tw-Transmitter, 3rd Order Cmpnents (2Tx 3rds) Three-Transmitter, 3rd Order Cmpnents (3Tx 3rds) Tw-Transmitter, 5th Order Cmpnents (5Tx 5ths) When creating an intermdulatin-cmpatible frequency set any cmbinatin f these 3 tests can be applied in rder t btain the desired level f reliability. In fact, these three tests can be cmbined in different ways in rder t generate frequency sets with 7 different levels f stringency: The Frequency Set Is Generated Stringency Intermd Prducts That Are Tested When 2Tx 3rds 3Tx 3rds 2Tx 5ths Strictest YES YES YES Strict YES YES Mderate YES Lenient YES YES Weak YES Weaker YES Weakest YES YES What this means is that a frequency set created under 'Strictest' cnditins is guaranteed t be free f intermdulatin interference caused by 2Tx 3rd, 3Tx 3rd and 2Tx 5th intermdulatin prducts. Similarly, a frequency set created under 'Strict' cnditins is guaranteed t be free f intermdulatin interference caused by 2Tx 3rd and 3Tx 3rd 28 / 48

29 intermdulatin prducts. And s n... Ideally ne wuld always want t use a frequency set created under 'Strictest' cnditins because the frequencies within the set culd be assigned t different transmitters and the level f reliability wuld be very high (since interference caused by intermdulatin distrtin wuld be eliminated fr all intents and purpses). Hwever, fr practical purpses, it may nt be pssible t always create frequency sets f 'Strictest' stringency when yu have many transmitters yu need t assign channels t. Assuming that transmitter channels fall n 25 KHz bundaries, then fr a particular frequency range (e.g. 470 MHz MHz) there are a limited number f intermdulatin-free frequencies that can be cmputed. Furthermre, as the stringency is increased then the number f intermdulatin-free frequencies that are available ges dwn. That is, the size f the frequency set is determined by (a) the frequency range, and (b) the intermd stringency r cmpatibility level. Fr example -- let's take the frequency range f 470 MHz MHz and assume that transmitter channels fall n 25 KHz bundaries. The fllwing results are apprximatins: Stringency Frequency Set Size Strictest 16 Strict 17 Mderate 22 Lenient 32 As yu can see, the number f transmitter channels yu require will dictate the level f intermd stringency that can be applied in rder t generate a frequency set f sufficient size t accmmdate yur needs. In this example, if we required 26 channel assignments then we wuld create a frequency set f "Lenient" stringency. As a side nte, when it cmes t cnfiguring audi equipment, at the very least yur frequency set shuld be free f interference frm 2Tx 3rd-rder intermd prducts -- i.e. be f "Lenient" stringency r higher -- since these are the mst destructive. Near Hit Settings: Related t 'Stringency' is the cncept f 'Near Hits'. This means that in rder t qualify as a cmpatible frequency and be a member f a frequency set a candidate frequency must nt match an intermd prduct nr be within a specified distance f an intermd prduct. A 'Near Hit' setting specifies the minimum distance a candidate frequency must be frm an intermd prduct in rder t qualify as a cmpatible frequency. If a candidate frequency is t clse t an intermd prduct then it is disqualified. Fr example, by default, intermdcmpatible frequencies must be at least 99 KHz frm 2Tx 3rd-rder prducts, 49 KHz frm 3Tx 3rd-rder prducts, and 89 KHz frm 2Tx 5th-rder prducts. As the 'Near Hit' distance is increased then the frequency set becmes mre stringent, but that cmes at a cst -fewer candidate frequencies will qualify as members f the frequency set and, hence, the frequency set will be smaller. We suggest yu leave the 'Near Hit' settings at their default values. Step Size 29 / 48

30 Mst audi transmitters are designed t perate n channel frequencies that fall n 25 KHz bundaries -- i.e. they are "tunable" in 25 KHz steps. Given a frequency range (e.g. 470 MHz t 500 MHz) and a step-size f 25 KHz, then nly frequencies within that range and which als are multiples f 25 KHz are ptential candidates t be included in the frequency set that Pr Audi White Space Finder generates (prvided they als meet the stringency requirements described abve). We suggest yu leave the 'Step Size' setting at its default value f 25 KHz. Ignre Certain Intermd Prducts Intermdulatin prducts are calculated frm either tw transmitter frequencies (e.g. 2Tx 3rds, 2Tx 5ths) r three transmitter frequencies (3Tx 3rds). If yu prefer that Pr Audi White Space Finder ignre 3Tx 3rd prducts generated by 3 frequencies where at least ne f them is mre than 40 MHz distant frm the thers, then enable this setting by checking the CheckBx. By checking the CheckBx yu are telling Pr Audi White Space Finder t ignre certain intermdulatin prducts, thereby decreasing the stringency f the frequency set. Likewise, if yu prefer that Pr Audi White Space Finder ignre any prduct where at least ne f the transmitter frequencies is mre than 100 MHz distant frm the ther(s), then enable this setting by checking the CheckBx. Again, by checking the CheckBx yu are telling Pr Audi White Space Finder t ignre certain intermdulatin prducts, thereby decreasing the stringency f the frequency set. By default Pr Audi White Space Finder des nt ignre any intermd prducts when generating a cmpatible frequency set. Hwever, if yu find yurself in a situatin where yu need t slightly increase the size f a frequency set, then yu might cnsider checking ne r bth f these CheckBxes. Interference frm intermdulatin distrtin may be less 30 / 48

31 f a prblem when transmitters are perating in bands that are many MHz apart frm ne anther. Generate Frequency Set Frm Spectrum Trace Pr Audi White Space Finder allws yu t generate a frequency set that takes int accunt interference frm bth RF interferers and intermdulatin prducts. This is a very pwerful feature -- it allws yu t make channel assignments using frequencies that are free f RF interference and intermdulatin distrtin. The results displayed in the 'White Spaces and Intermd-Cmpatible Frequencies' view are sufficient fr mst wireless audi installatins. The frequency set that is cmputed in realtime is free f RF interference and the mst destructive types f intermdulatin distrtin. Hwever, fr mre demanding scenaris, it is pssible t take the analysis a step further. By selecting the 'Intermdulatin Analysis' tab a new screen is displayed with additinal settings, grid and chart. [NOTE: While scanning is in prgress then this feature is disabled]. Initially the chart is blank and yu'll need t fill it with a spectrum trace. Yu can d this by pressing the 'Last Trace' buttn, which will retrieve the last spectrum trace (assuming yu had previusly perfrmed sme scans). Alternatively, yu can perfrm a ne-time scan by pressing the 'Refresh Scan' buttn. 31 / 48

32 After the RF spectrum data is laded then its trace will be displayed -- alng with a hrizntal, red line that indicates the "White Space Threshld". The 'White Space Threshld' slider cntrls the threshld signal strength (in dbm) belw which is cnsidered 'White Space' -- that is, frequencies nt subject t RF interference and which shuld be cnsidered ptential candidates fr the frequency set. When yu adjust this cntrl yu'll see the hrizntal, red line mve up and dwn accrdingly. Thse frequencies whse signal strength amplitudes exceed the threshld are cnsidered ff-limits and are lcked-ut -- that is, they will nt be cnsidered as candidates fr a frequency set. In additin t adjusting the 'White Space Threshld' yu shuld select a cmbinatin f intermd prducts yu wish t test fr frm the 'Intermd Settings'. The initial set f candidate frequencies frm which intermd-cmpatible frequencies are drawn include multiples f the step-size that als fall within the "White Space" -- i.e. belw the "White Space Threshld". After the "White Space Threshld" and 'Intermd Settings' have been accunted fr, press the 'Start' buttn t begin the cmputatin. 32 / 48

33 When the cmputatin has cmpleted the intermd-cmpatible frequencies that cmpse the frequency set are listed in the 'Results' windw. They are als displayed graphically -- as shwn abve. Here yu see that the intermd-cmpatible frequencies (the vertical white lines) nly ccur within the "White Space" regins. 33 / 48

34 Reserved Frequencies Pr Audi White Space Finder allws yu t add a label r descriptin t any frequency within the frequency set. When yu left-click n a frequency in the results windw then a DialgBx appears that allws yu t enter sme text. When yu are finished then press the 'OK' buttn. If yu chse t create a PDF reprt the descriptin yu just entered will als be included. Alternatively, yu can use this DialgBx t exclude a frequency frm all future intermdulatin analyses. Adding a descriptin serves anther imprtant purpse -- it designates that frequency as a "reserved" frequency. A reserved frequency is ne that will always be included in the frequency set that results frm an intermdulatin analysis. Reserved frequencies prvides a means fr a user t enter ne r mre frequencies int the crdinatin fr thse instances where a particular device is cnsidered mandatry. Fr example, facilities r events ften have a pl f existing equipment t which channels will need t be added. Als guest systems using precnfigured channels may have t be integrated and crdinated with resident systems. There are tw ways t add Reserved frequencies -- frm the main menu select 34 / 48

35 Intermdulatin / Reserved Frequencies, r frm the Results windw left-click n a frequency and add a descriptin (as explained abve). When yu use the latter methd and then g t Intermdulatin / Reserved Frequencies, yu shuld see the frequencies have been added. T cpy, cut r paste a descriptin, select a frequency in the results windw and right-click. If a descriptin is 'cut', then the crrespnding frequency will be remved frm the reserved frequencies. Similarly, if a descriptin is 'pasted', then the crrespnding frequency will be added as a reserved frequency. 35 / 48

36 Manually Lckut Frequency Ranges 36 / 48

37 Pr Audi White Space Finder's lckut feature allws yu t manually lckut frequency ranges f yur chsing. Frequencies within the lcked-ut regins are remved frm cnsideratin as ptential candidates fr a frequency set. This feature is accessed frm the main menu by selecting Intermdulatin / Lckut Frequency Ranges. When the 'Lckut Frequencies' dialgbx appears enter 'Start' and 'End' frequencies, in MHz, and press the 'Add' buttn. The frequency range yu just entered will be added t a grwing list f frequencies that will be excluded frm the frequency set. 37 / 48

38 The frequency set shwn abve was generated with tw regins lcked-ut: MHz and MHz. As yu can see, the resultant frequency set des nt include any frequencies frm thse regins. Lckut DTV Channels 38 / 48

39 Pr Audi White Space Finder's intermdulatin analysis allws yu t manually lckut DTV channels f yur chsing. This feature is accessed frm the main menu by selecting Intermdulatin / Lckut DTV Channels. Fr channels yu select their crrespnding frequency range is lcked-ut f the intermdulatin analysis -- that is, frequencies within lcked-ut regins are remved frm cnsideratin as ptential candidates f a frequency set. Channel Bands 39 / 48

40 Pr Audi White Space Finder's 'Channel Bands' feature allws yu t rganize the frequencies within a frequency set int different grups based n their frequency ranges. This feature is accessed frm the main menu by selecting Intermdulatin / Channel Bands. Often it is the case where audi engineers are wrking with a variety f different wireless audi equipment that perate in different frequency ranges. Hwever, because the equipment perates within clse gegraphical prximity then ne frequency set is applied when cnfiguring the frequency crdinatin and assigning channels t transmitters. In additin t setting the Start/End frequency fr each band, yu can als assign a shrt name r label. If yu wish, channel bands may verlap ne anther -- in which case certain frequencies may belng t mre than ne channel band. It is imprtant t nte that frequencies nt included within a channel band will be lcked-ut f the intermdulatin analysis. 40 / 48

41 In the example abve we've divided ur frequency range (470 t 700 MHz) int 6 channel bands. Under the 'Band' clumn is listed the channel band's label that each frequency belngs t. Als, the number in brackets is the ttal number f frequencies that fall within that channel band. As seen abve, the frequency MHz falls within tw channel bands -- "CH-BAND2" and "CH-BAND3". "CH-BAND2" includes a ttal f 4 frequencies and "CH-BAND3" includes a ttal f 9 frequencies. Just t be clear, all channel bands (and frequencies) belng t the same frequency set -- hence, frequencies in different channel bands are still intermd-cmpatible. Exprt Frequency Set 41 / 48

42 Pr Audi White Space Finder has the ability t exprt the frequency set data (i.e. the list f frequencies in the 'Results' windw) in XML frmat that is recgnized by bth Pr Audi White Space Finder and Intermd Assist. This is useful if yu wish t use the results as input data t anther prgram, such as Intermd Assist, fr the purpse f perfrming additinal analyses. An exprted frequency set can als be imprted int Pr Audi White Space Finder and used as the frequency set that is applied during real-time intermdulatin analysis. Fr mre infrmatin yu can learn mre in the 'Cntrls' sectin f the Cntrl Panel. Yu can access the Exprt feature frm the main menu by selecting Intermdulatin / Exprt Frequency Set. Create Reprt The 'Intermdulatin Analysis' sectin has its wn reprt generatin capability that is separate frm the rest f the applicatin and different than the ne accessed frm the main menu. Press the 'Create Reprt' buttn and yu will be prmpted fr a flder and filename in which t the save a reprt file. An Adbe PDF-frmatted file will be created that includes the graphical chart depicting the members f the frequency set, alng with a listing f the 42 / 48

43 frequencies and their labels (taken frm the 'Results' windw). At the same time, Adbe Reader will be launched s yu can verify the cntents f the reprt yu've just created. Als, by selecting File / Open Reprt... frm the main menu yu can pen and view Adbe PDF-frmatted reprts yu've created (r any ther PDF file). Creating Reprts Pr Audi White Space Finder has an easy-t-use reprt generatin capability. Select File / Create Reprt frm the main menu and yu will be prmpted fr a flder and filename in which t the save a reprt file. An Adbe PDF-frmatted file will be created that includes all charts. At the same time, Adbe Reader will be launched s yu can verify the cntents f the reprt yu just created. Als, by selecting File / Open Reprt frm the main menu yu can pen and view Adbe PDF frmatted reprts yu've created (r any ther PDF file). User Defined Prfiles Pr Audi White Space Finder supprts tw types f prfiles -- pre-cnfigured r built-in (discussed in the Cntrl Panel sectin) and user-defined. The difference is that userdefined prfiles are created by yu and stred as files that can later be laded int the applicatin. Prfiles cntrl many imprtant parameters, including the fllwing: Start and End frequencies, Mnitred Frequencies settings and transmitter signal bandwidth and spacing. When yu lad a user-defined prfile then these settings are immediately applied thrughut the applicatin and will be in effect the next time the 'Start Scan' buttn is pressed. As a side nte, the user-defined prfiles can nt be accessed while the receiver is actively scanning. That is, if the receiver is scanning and yu wish t use apply a userdefined prfile then it is necessary t first press the 'Stp Scan' buttn. 43 / 48

44 T save the current settings as a new, user-defined prfile then select File / Save As Prfile frm the main menu. A 'Save Current Settings As A Prfile' DialgBx will pen and yu can specify a filename and lcatin f yur chice. The default lcatin is the 'Prfiles' flder ne level belw the Pr Audi White Space Finder's installatin directry and the default file extensin is *.wsf (fr White Space Finder Prfile). After specifying a filename and lcatin yu will then be asked fr a shrt descriptin fr this prfile (see belw) that will appear in the Cntrl Panel's title bar. When a user-defined prfile is currently in use then the descriptin that yu entered (abve) is used in the applicatin's title bar (see belw). This is yur visual cue as t which user-defined prfile was last saved r pened. 44 / 48

45 T pen a user-defined prfile that yu had previusly created, select File / Open Prfile frm the main menu. A 'Select White Space Finder Prfile' DialgBx will pen and yu can navigate t the flder where the prfile was last saved. Select the desired prfile (as yu wuld when pening a file in any ther type f applicatin) and press the 'Open' buttn. The settings stred in the prfile will then be immediately applied thrughut the applicatin and will be in effect the next time the 'Start Scan' buttn is pressed. Als, the applicatin's title bar will change t reflect the descriptin f the newly applied prfile (see abve). Save Spectrum Trace Spectrum traces created by Pr Audi White Space Finder can be saved t file and used by ther prgrams -- e.g. Intermd Assist can use these traces t define white space regins when perfrming intermdulatin analysis. T save the current spectrum trace t an XML data file then select File / Save Spectrum Trace frm the main menu. A 'Save Spectrum Trace T PAWS4400 Frmat' DialgBx will pen and yu can specify a filename and lcatin f yur chice. The default lcatin is the 'DataFiles' flder under '\Prgram Files\RatinalWaves\Cmmn'. 45 / 48

46 Hardware Specificatins Specificatins fr the Signal Hundä spectrum analyzer (taken frm 46 / 48

47 47 / 48

48 Cntact Us The Pr Audi White Space Finder applicatin sftware was created and cpyrighted by Ratinal Waves, LLC Ó2011. Fr PAWS4400 sales and technical supprt please cntact Ratinal Waves at: Ratinal Waves, LLC nd Ave NE Redmnd WA USA Tel: General infrmatin and sales: Technical Supprt: Web Site: / 48