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