Uplink problem

Satellite ground station at AIT is surrounded by a metalic fence (see pic. 1); a wooden shade have been erected in front of the dish to protect a workshop (located at the right of the picture) from the sun glare coming from the dish.

Pic. 1: the wooden shade in front of the satellite dish.

As a reminder. the elevation of JCSAT3 if 54.6 degrees. The red lines on the picture show where the measurement were done, it can be clearly seen than the horizontal line is much more longer than the vertical line, so the elevation of the shade is less than 45.

The measurement have been physically done by using a length of string, to compare the horizontal distance between the shade and the base of the dish, and to compare the vertical distance between the point located at the horizontal projection on the shade, of the base of the dish, and the top edge of the shade.

Pic. 2: the measurements for elevation.

On the diagram (see pic. 2) north is located on the top. The azimuth of AIT earth station is 114 degrees East.

The red line shows how the elevation of the wooden shade has been measured, considering that the azimuth was full East. If the real azimuth had been used, the horizontal distance between the base of the dish and the shade would have increased, so the elevation would have dimisished. This leads me to say that the wooden shade is not interfeering with the uplink signal.

The blue line correspond to the measurement of the elevation f the metalic fence. For that case, I used the real azimuth and measured an elevation below 45 degrees, that should be much into the required margins.

Contact: Olivier Nicole

Last update: Mon, Nov 09, 98