WiFi Lab C. Equipment Needs:

Transcription

1 WiFi Lab C Event Objective: Teams will cnstruct an antenna prir t the turnament that is designed t transmit a signal at 2.4 GHz and cmplete a written test n the principles f electrmagnetic wave prpagatin. Equipment Needs: Tables fr the students taking tests, depending n the maximum number f teams per hur A transmitter fr cnnecting student antennas (see WiFi Transmitter Guide and rules fr mre infrmatin) A Laptp with inssider r related sftware fr measuring signal strength f 2.4 GHz WiFi signal cming frm antenna A cart that can hld the laptp and mve easily A tape measure t determine the distance between the transmitter and the laptp (receiver) At least ne table fr cmpleting scring Cautin tape fr making an area fr the impunding f student devices and charts Cautin tape fr the antenna test area Signs that tell spectatrs NO CELL PHONE USE IN THE AREA, NO COMPUTER/TABLET USE IN THE AREA, IMPOUND AREA, and SPECTATOR AREA if the event is run spectatr-friendly. Number f Vlunteers Needed: One impund/table greeter that can be used as a test vlunteer r transmitter vlunteer during the day One transmitter vlunteer If pssible, anther test vlunteer wh can grade tests during the day as well as scre charts Fr the state turnament yu will be prvided names and cntact inf fr yur vlunteers and YESS team. It is required that yu cntact them prir t the turnament t relay any event-specific infrmatin. Prir t the Event: Read and re-read the event rules Get in cntact with turnament directr t learn mre abut cmpetitin area and determine the maximum pssible distance (the farther the distance, the better, cnsider gymnasiums, lng hallways, r ther very lng distances). Get a cpy f the fficial scring/check-in wrksheet n the natinal website: sinc.rg Print ff enugh check in wrksheets frm the natinal website t have ne sheet per team, plus a few extra sheets. If yu have time, put the names f the teams n the tp f the sheets (ne team per sheet) and, if yu have the times that each team will cmpete, put the team s cmpetitin

2 time als n the tp f the sheet. Put the team names int the scring spreadsheet frm the natinal website t save time n cmpetitin day. Create fake results t test the scring spreadsheets, including Exam Scre, Antenna Successful Cnnectin Distance (m), Chart Scre, Impund Bnus (y/n), and Max Distance Bnus (if applicable). Ensure that yu knw hw t prperly use the scring spreadsheet and crrect results are created by manually calculating the scres. Review event penalties: Devices nt impunded have their successful cnnectin distance multiplied by 0.7 Devices that are unsafe r will damage the transmitting device are nt allwed t be tested Devices that are fixed/crrected frm unsafe r damaging t the transmitting device during the five minute testing perid have their successful cnnectin distance multiplied by 0.7 The Written Test (Exam Scre ES): Finalize writing the test well befre the cmpetitin (if pssible) and check it ver well. Cnsider having anther persn evaluate the test. It shuld have a mix f easy, medium, and hard questins and tiebreaker questins t separate teams. Be sure t fllw the tpics in the rules fr the test. Fr 2018, there must be at least five questins frm each f the fllwing areas: The Electrmagnetic Spectrum, radi waves, and EM wave prpagatin Relating velcity, wavelength, and frequency fr waves, with emphasis n radi waves Cmmn antenna designs, cmpare/cntrast different types f antennas Gain patterns, the radar equatin, impedance, bandwidth, nise, and infrmatin Have a variety in the difficulty f questins within each tpic thrughut the test Student cmpetitrs must be given a minimum f 20 minutes t cmplete the written test. Aim fr the fllwing gals fr the written test: There shuld be n perfect scres r very few perfect scres There shuld be n zer scres High scre in the target range f 75% t 95% Lw scre is in the target range f 10% - 30%

3 Less than 5% f teams scre abve 90% Less than 5% f teams scre less than 15% Less than 10% f teams are invlved in ties A gd mix f easy, medium, difficult, and extremely challenging prblems will ften btain the abve results. Als, make sure the test is lng enugh t separate the cntenders frm the pretenders...remember, kids can bring in a binder! When scring the test, the team that earns the highest scre n the test earns 45 pints. All ther team s scres are divided by the highest raw exam scre and then multiplied by 45 (rule 6d). Day f the Cmpetitin: Shw up at yur rm as early as yu can (even the day befre if pssible) Set up the rm and WiFi transmitter as early as yu can (even the day befre if pssible) Lay ut tests, answer sheets, scrap paper, equipment, and ensure yu have planned ut walkways and lab space Prvide general instructins n a white/chalkbard r verhead if available Cver the plan with all vlunteers, including all f their assignments Determine the cnnectin threshld dbm reading with the 3.1 cm mnple antenna at a distance f 3.0 m. D nt share this number with student cmpetitrs. Student cmpetitrs are nly infrmed if their device makes cnnectin at a certain distance r nt. Impunding f Devices: Antennas that are impunded in a bx receive an Antenna Bnus (AB) f 3 pints. Students must impund antennas and charts befre cmpetitin begins during the impund time perid. Teams that fail t impund their antennas will have their maximum successful cnnectin distance scre multiplied by 0.7 Tls, supplies, and three-ring binders d nt need t be impunded Assign at least ne individual t impund. It is critical that students avid stepping n r damaging ther devices when checking in OR when retrieving devices fr cmpetitin Have students line up fr check-in, first cme, first served. Students needing t fix r change their device need t exit the line and g t the end. Anybdy in line at the end f the impund windw is allwed t impund their device with n penalty, but the students must be IN LINE at the end f the impund windw. Make sure that the impund area is taped ff and nt accessible t students, caches, r spectatrs. Make sure that student s impunded antennas and charts are in a safe area. Cmpetitin: Meet all teams utside the rm fr final instructins including Turning all cell phnes ff and clearly explain what happens if a cell phne shuld g ff (the Event Supervisr may ask them t raise their hand and nt tuch the cell

4 phne at all) Explain any ther plicies and if yu have assigned seating r what they can d (i.e. can they lk at the test) Let teams in ne at a time Check that they have wristbands if used at yur turnament Check that their binders d nt have lse material by gently shaking them by the spine t see if anything falls ut...if any papers fall ut they are nt allwed t be used in the exam (especially fr state turnament). Allw single team members t enter if they are waiting fr their partner Generally a persn can shw up late t an event, but after the event has started yu may nt leave and reenter (s if the teammates have t leave, they cannt return) G ver the specifics n the test and n hw the antenna test will wrk, answering questins Begin the examinatin perid and start whatever timer yu will use Always have the exam be a minimum f five minutes less than the alltted sessin time and be cnsistent amng all sectins (i.e. if they are 50 minute sessins, yu have a 45 min exam) Call up teams ne at a time t test their antenna Teams are allwed t send nly ne persn up t d the antenna test t allw the ther team member t cntinue t wrk n the test r they may bth d the antenna test Ensure the team fills ut the gray area f the checklist (available frm sinc.rg) Ensure that ne vlunteer is psitined at the transmitter t help the students (if needed) and ne vlunteer/lead event supervisr (preferred) is psitined at the receiving laptp keeping an eye n the signal strength. G ver the prcess with the students: Students start by selecting an initial distance (measured t the nearest 50.0 cm) Vlunteer starts the five minute timer fr the testing perid Students cnnect antenna t transmitter and infrm vlunteer r event supervisr when they are cmplete Students step away frm the transmitter setup and the five minute timer is paused while cnnectin is assessed Lead supervisr watches the dbm reading ver a 10 secnd perid and determines if average is equal t r higher than the threshld dbm reading, which determines cnnectin Students are infrmed if cnnectin is achieved r nt If cnnectin is achieved, students may select a farther distance, measured t the nearest 50.0 cm. If cnnectin was nt achieved, a distance n farther than the mst recent failed cnnectin attempt may be selected. The five minute timer is started again and the students can mdify the cnnectin f their antenna t the transmitting device. When they are ready they infrm the vlunteer/event supervisr and step away frm the transmitting de-

5 vice. The prcess is repeated until three cnnectin attempts are cmpleted r the five minute testing perid expires. Students are asked if they have any questins, and if nt, prceed with asking students fr their first cnnectin distance. Start the timer fr their setup. Students can begin cnnecting their antenna t the transmitter Give teams a 60 secnd warning when they are abut t run ut f time fr ding the antenna test Once the students are ready t test their antenna they shuld infrm yu r the vlunteer and step away frm the transmitter. Event supervisrs must recrd each cnnectin distance attempt, whether cnnectin was successful r nt, and if the cnnectin was successful at the farthest distance, the dbm reading shuld be recrded in case f the max distance bnus (multiple teams achieve cnnectin at the furthest distance). Enter the data n the checklist Have the students sign and agree t the numbers n the checklist If there is a disagreement r smething unusual, make as many measurements as pssible and take pictures if pssible t mark what is unusual. Als put all the additinal measurements and ntes n the back f the frm. The students shuld still sign it, even if they plan n filing an arbitratin, but with the additinal infrmatin n the frm yu can easily assign whatever pints the arbitratin cmmittee determines (it is tugh t retest an antenna) Reset the antenna test transmitter and receiver in preparatin fr the next team Call up the next team When scring teams antennas, the farthest successful cnnectin distance earns 42 pints. All ther team s farthest successful distance is divided by the farthest successful distance f the day and the multiplied by 42, accrding t rule 6c. If tw r mre teams achieve successful cnnectin at the farthest distance, the team with the highest dbm reading earns an additinal 5 pints, called the Max Bnus (MB) by rule 6g. If a team has n successful cnnectins, then their antenna scre must be a zer. Chart Scre (CS) During the day, if yu have enugh vlunteers, scring f the graphs/charts may take place. These graphs must be impunded and students must impund up t fur graphs fr maximum pints. Graphs may be hand drawn r cmputer generated. The scring rubric fr the graphs is as fllws (partial credit may be given): 2 pints fr including data spanning at least 5 m f distance 2 pints fr including at least 10 data pints 2 pints fr prper labeling (e.g., title, team name, units) 1 pint fr each graph r table turned in (up t 4 ttal, as lng as they are nt all the same)

6 Scring at End f Day: Calculate a team s final raw scre by adding up the Exam Scre (ES), Antenna Scre (AS), Chart Scre (CS), Impund Bnus (IB), and Max Bnus (MB). The maximum scre pssible is 105 pints, nly if multiple teams achieve cnnectin at the farthest distance. Otherwise, the maximum pssible scre is 100 pints. Write all team final raw scres n the prvided screcard and take all tests, team scre checklists, and screcards t scring at the end f the day.