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Mapping the Global Reach of Satellites
photo: The First Satellite Link on the US Embassy London Today in the global world of instant communications, access to thousands of databases, and information about virtually everything it is hard to realize that twenty years ago we lived in a more secret society, where global information distribution was only a dream. The satellites were firmly in the grasp of national telecommunications monopolies and details of radio frequencies were guarded as state secrets. In the UK all satellite footprints, freely available in the US were classified "Confidential" and were the sole property of British Telecom. It was an imprisonable offence in the UK to ask about the footprint and frequency of CNN over satellite. Slowly, governments realized that this situation could not continue. The number of enthusiasts building satellite systems was increasing. Far too many to intimidate and prosecute. Finally the blow for freedom came, from all places, the Soviet Union. They announced that anybody could watch Gorizont, the Soviet satellite, and could do so on a small 4 foot dish. This appalled the western governments, Soviet propaganda being beamed directly into Western houses. Anyone who accessed the Gorizont satellite would have been excited, for a few minutes. Whilst the technical achievements were impressive, the programming was rubbish, boring, and the signal of poor quality. What goes for TV in Siberia, is far removed from suburban Kensington. In Washington, D.C. at this time, President Reagan too was having problems with images. This time over his invasion of Grenada. A decision was made to get into the business of global satellite television, just as VOA had done with HF radio at the end of WW2.Down in Atlanta, GA Ted Turner, and Henry Gillespie were looking towards Europe, and South East Asia to expand their fledgling CNN satellite television news. The BBC was too realizing that they should be in the business, as they owned the highly respected BBC World Service. Unfortunately satellite television used the same frequencies as telco microwave links. And as the telcos controlled allocations of frequencies, design parameters and owned and operated the links, they could do just as they wanted, with no oversight, nor quality control. Here lied the first problem. To receive the very weak signal from 22,000 miles out in space, a high gain receiver had to be employed. If the telcos were blasting the site with a microwave signal, many thousand times more powerful, any satellite signal would be swamped. Outside the USA, Telcos refused to disclose their frequencies, claiming them as secrets, whose disclosure would threaten national security. In the USA, microwave routes, frequencies and contents were available for planning. Worse still, the Telcos were less than efficient in their engineering of microwave links, and lossy sidelines were everywhere. These had to be found, and measures take to shied, or position the satellite dish, for maximum reception quality. It was an offence, in most countries, to posses frequency measuring equipment, and be able to analyze RF signals. Without that information private satellite networks were impossible to create. The world of global satellite communications therefore owes a debt of gratitude to the US Government for funding, and facilitating the first global analysis of satellite signals, and Radio Frequency Interference, starting mid-1984. This was done after enormous negotiation with governments around the world, against immense opposition from the Telcos. In 1985 I created Satellite Communications, Ltd. and two operations centres in rural England, equipped with a broadcast TV studio, to undertake the first global RF sweep. These were based on military intelligence principles for gathering, analyzing and reporting multiple technical, political and logistical inputs, and creating a simple briefing report for top politicians.
Firstly a sweep was done across Europe. London, Paris, Rome, Bonn, Brussels, The Hague, Geneva, and Madrid. This was to answer the question, "Is direct satellite TV possible in a major city, at Ku frequencies?" Theoretical models had said yes, but without accurate information, withheld by the Telcos, it was madness to commit the millions needed for the project. Truly portable miniature RFI analyzers were unheard of. We first had to create a simple, easily transported, hand held device, that can be used whilst scrambling over crumbling roofs in Europe's ancient cities.
Later, when the US Government had committed to the WorldNet Project, and our work became accepted by governments, we tested this early device against the portable spectrum analyzer, provided by Washington. It was remarkably accurate, and was still being used many years later, for rapid readings. Over the next year a complex pattern of interference was overlaid on the European, and Middle Eastern map. Stretching from Norway, to Egypt, and from Morocco to Israel. It was a revealing patchwork, showing in many cases Telcos had been somewhat negligent in their allocation of frequencies to themselves. Many of the readings had to be taken on rickety rooftops, some several hundred years old. In some cases the local population regarded people crawling over roofs, with space-age devices pointing at them, to be an invitation to take pot-shots. In other locations, the best place was at the top of a forty storey, or more building, with windspeeds to make even the most brave of us worried. In other places the sense of historical significance was brought home. Whilst in Rome the Vatican requested a survey of the private Vatican grounds, for a planned satellite link it was contemplating. After sweeping all the possible locations, the Archbishop accompanying me, casually noted that only Marconi had done a similar study, for the original HF Vatican radio, many decades before. Many unconnected items were found to cause problems. Many of the US manufactured microwave detection devices were on the same frequency as European satellites. They were not supposed to be installed in Europe, but many US owned buildings had them anyway. We found many holes in electronic security screens and quietly showed them to the Marines, who fixed them immediately. With newly developed portable Spectrum Analyzers, the study was expanded to include all of Africa, and across South East Asia to Japan, and mainland China. From freezing blizzards in Helsinki, to sweltering Monsoons in Singapore, and from friendly crowds in Australia, to rock throwing mobs in Karachi, Pakistan. In all over 120 major cities were visited, RF mapped and either receiving platforms developed, or RFI shielding measures created. Over 650 briefings, and high-level meetings were undertaken, with Ministers, Ambassadors and telco chiefs. The survey of the Far East brought many new challenges, especially weather related. In some countries the roofs were, to say the least, dangerous. In one country I took one look at a key building requested to be included in the survey, declined to conduct a survey, and thanked myself a month later, when it collapsed on it's own. Climbing around roofs is not a regular habit, and in many countries the roof is where the garbage is tossed, to be eaten by the birds, and dry in the sun. A whole new learning experience. From 1986 onwards the governments were eager to cooperate, and meetings with government Ministers, officials, and Telcos became more relaxed, and an air of cooperation, and "Me too!" had replaced, the "No Way!' of earlier confrontations. Local television stations requested a visit, and a quick assessment of their equipment, and advice on expansion into the satellite age. This gave a unique experience of working with media in over 50 countries, and seeing "behind the scenes" in television and radio studios, of many political persuasions. Fortunately the introduction of Fiber Optic cable marked the end of many of the clashes between satellites, and microwave links. But the reallocation of many of the frequencies for wireless application will again cause problems. Today, with a liberal cooperative environment, let us not forget the tens of thousands of miles traveling, millions of readings, and hundreds of meetings that laid the foundations of the modern satellite communications infrastructure. And let us all thank President Ronald Reagan for having both the vision, and determination to see through our global survey. His persuasion opened many closed doors. Also the vision of Ted Turner, who seeing the success of CNN in rural America, projected it's concept around the globe.
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Working closely with US, European, and Japanese manufacturers we created a simple, yet accurate, directional RFI meter. It could be easily carried in a suitcase, and ran off "D" size cells. The Japanese had managed to cram a complete Ku band satellite receiver into a camera case, and add a meter for measurements.