Diary of Wednesday, 16th February 2005

Prepared by: Beatriz Cabrera Lozano

We were working all day in the laboratory, which is like our 2nd room after our rooms here, because every day we spend most of the time there working and sometimes watching movies (it includes snack and something to drink), but we always enjoys our time there.

Today was special because we were visited by the RAI TV cameras and its interviewer. We were filmed all the time working (after 5 minutes, we are already accustomed to the camera) the group coordinators and our tutors were interviewed.

At 9:00am, Mr. Carlo Fonda started his session, explaining how we can make antennas by ourselves, then we started to measure and cut wire, we soldered these parts with the N-Type female connector, bent and stretch them until obtain the required form.

In this way, we got a great omnidirectional collinear antenna for 2.4GHz, designed to transmit a vertically polarized signal, It can be used for indoor or outdoor Point to Multipoint short distances coverage, its gain could be between 7dBi and 9dBi. We had checked with the oscilloscope and a directional coupler, if the antenna was tuned in the correct frequency and we read the value of the reflected power (You can see this procedure here: http://wireless.ictp.trieste.it/handbook/C6.pdf page 120)

Then many groups had to improve their antenna to obtain the wished parameters.

After rest during the launch break, Carlo explained us the way to build another kind of antenna, which offers good directivity and gain for Point Multipoint communications, with a beamwidth of around 60 degrees and its gain could reach 10to 12dBi. It has the shape of two squares of the same size of ? wavelength as a radiating element and of a metallic plate or grid as a reflector.

Coming soon on RAI 3 TV, you could see all these interviews and all of us working in the laboratory.

Beatriz Cabrera Lozano
Department of Electronic Engineering
Pontificia Universidad Católica del Perú
Lima - Perú