Some Weston Antennas - clockwise from top left:
9.5 metre antenna in Munich
13.5 metre antennas near Berne
11 metre antenna in London
Drive and control system
Antenna pedestal with "Contra-Torque" drive system in factory
I have just published a science fiction short story, Venus Express. I have always been interested in reading science fiction, but for some time I have found it difficult to find sci-fi novels that interested me. I dislike fantasy sci-fi, and I am not very keen on books which depend for their plots on breaking the laws of physics as they are presently understood.
Venus Express draws on my experience of starting and running a business, Weston Antennas, which designed, manufactured and installed large satellite earth station antennas. The antenna on the cover of Venus Express is an 11 metre diameter antenna which I designed, and which was made by my company in Piddlehinton, Dorset, and installed at BBC Television Centre in London.
This was the first transmit antenna I had designed. The company initially specialised in manufacturing large receive only antennas, especially ones operating at higher Ku-Band (10.75 – 12.5 GHz receive). At these very high frequencies, the surface of the antenna has to be very accurately made, and this surface accuracy must be maintained when the antenna is pointed at different elevation angles, and when the wind blows on it.
Transmit antennas have to comply with very strict standards so that they have a “clean” beam, with very low sidelobes. Sidelobes can “light up” a satellite adjacent to the one illuminated by the main beam of the antenna, and their reduction below the required envelope tests the limits of what can be achieved in mechanical design.
I thought of the Venus Express plot when testing the performance of a 13.5 metre antenna in Switzerland. This was done by pointing the antenna at Cassiopeia A, a radio star whose flux at various frequencies has been measured and tabulated, and I speculated on what might have happened if we had detected a signal in the star’s radiation.
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