7/22/2019 Antenna Measurement experiment

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Antenna Measurement.doc 1 of 1

Measurement of Radiation Characteristics

Goal :1. Measure the radiation pattern of the antenna.2. Calculate the gain of the antenna.3. Measure the axial ratio of circular and linearly polarized antennas and compare.

Antenna pattern measurement:1. Connect an antenna to one of the ports of the network analyzer.2. Attach the antenna under test to a turntable and connect it to the other port of the network

analyzer.3. Rotate the antenna under test and note down the transmission coefficient.4. Plot the radiation pattern as a function of angle.5. Repeat the experiment for two principle polarizations of the antenna.6. Plot the radiation pattern on a polar plot and calculate the pattern directivity from the plot.7. List the sources of error and precautions you took while carrying out these measurements.

Antenna Gain Measurement:1. Align two identical test antennas such that their main beams are pointing at each other.2. Measure the transmission coefficient.3. Compute the gain of each of the antennas using Friss Formula.

Axial Ratio Measurement:1. Align the test antenna-1 with a linearly polarized antenna such that their main beams are

pointing at each other.

2. Rotate linearly polarized antenna about the line joining the two antennas and measure thetransmission coefficient as a function of angle.3. Repeat the procedure for test antenna-2.4. Calculate the axial ratio of each of the antennas.

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