Dear All,
Yes, those slightly elevated coastal ducts are tricky.
I well remember driving down the A20 dual carriageway to Dover docks. At 600ft asl, normal UK FM, at 300ft, an eruption of Netherlands and French FM, at and below 100ft normal UK FM again.
There is an interesting cold war era paper on the Swingate-Houtem 4GHz links which describes, with measurements, the way 4 dishes at different heights were used in an elaborate diversity system to avoid link failure from such ducts.
The same arrangement has been reinstated by the current, non-military users of the route.
Regards,
Alwyn
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Alwyn Seeds, Director
114 Beaufort Street (Management) Company Ltd.,
114 Beaufort Street,
London,
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114 Beaufort Street (Management) Company Ltd., Registered in England and Wales: No. 02797775 Registered Office Address: 114 Beaufort Street, London, SW3 6BU
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