cantenna - accelerators.org.au
Transcription
cantenna - accelerators.org.au
CANTENNA Mark, Steven, Dimitris (consultant) 24/01/14 ASAP2014 EXAM 1 24/01/14 ASAP2014 EXAM 2 REAL ITY • Started with dipole antenna (coax with copper wire aGached to end) to compare λ/4 with theory and learn to use network analyser • Built cantennas with esKmate of the probe length from dipole, and shortened the probe unKl a maximum gain at characterisKc f = 2.55GHz of the cantenna • Constructed and tested the pipe-‐cap filter and successfully (with extreme loss) filtered all but a narrow frequency band • Demonstrated radar with two cantennas • TransmiGed using frequency generator at 2.4GHz and jammed wifi access in the lab 24/01/14 ASAP2014 EXAM 3 Band-‐Pass Filter • Peak resonant frequency increases with decreasing probe length • Increasing length of screw decreases frequency • Very lossy filter 24/01/14 ASAP2014 EXAM 4 Sending and Receiving 2.4GHz (WiFi) 24/01/14 2.55GHz (Cantenna) • Sent characterisKc frequency of the cantenna (2.55GHz) with frequency generator • Received on wide band with the other – can see WiFi • Tuning transmiGer to WiFi frequency (~2.4GHz) resulted in jamming wifi access in the lab ASAP2014 EXAM 5 Radar • Pulse one cantenna and receive with the other, and observe transit Kme in reflecKon of RF • Response less using more absorbent material 24/01/14 ASAP2014 EXAM 6 Acknowledgements • Thanks to all the lecturers and tutors for a great school! • Special thanks Ralph for drilling holes our cans and finding nuts and bolts for us (do we really need to return them?) • hGp://www.turnpoint.net/wireless/cantennahowto.html • hGp://w1ghz.org/new/Pipe-‐cap_Filters_Revisited.pdf 24/01/14 ASAP2014 EXAM 7 24/01/14 ASAP2014 EXAM 8