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EXECUTIVE SUMMARY

This report is an interim report, scheduled approximately halfway through the Committee’s study. It will be followed by a final report, due in 1989. Some of the study tasks, such as those dealing with DBS-A and emergency preparedness, are essentially complete. Consequently, this constitutes a final report on those efforts. However, a major study effort directed at antenna and propagation considerations is not yet complete and what is reported here is thus, by necessity, somewhat preliminary.

SOME BACKGROUND

The predecessor committee’s final report (National Research Council, 1986) made several recommendations intended to improve the Voice of America’s (VOA’s) technical and managerial position and result in a more efficient operation. Some of them have been implemented; some have not. The reasons for non- (or partial) implementation of those former recommendations are varied and in many cases outside VOA control; they include lack of a suitable staff or resources, lack of a clear mission direction from outside the VOA, and internal preoccupation with a technical upgrade program made chaotic by recent geopolitical changes and by recent and severe budgetary constraints imposed from without. Considering the situation as it existed two or three years ago and the problems that now exist, it is important to recognize that what was said then was predicated on the continuation of a strong, well-financed upgrade with staffing commensurate with the needs.

This Committee is concerned about some of the recent negative press articles that quote from several reports, including that of the predecessor committee, now nearly two years old with much of it history. The present environment in which the VOA must operate is quite different from that of two to four years ago. Consequently, much of the recent criticism appearing in the media is based on statements and conditions that are no longer valid. It is, therefore, either off the mark or unfair.

The Committee notes that VOA Engineering has, in the past, attempted to cope with a large increase in procurement authority imposed suddenly on



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Antennas, Satellite Broadcasting, and Emergency Preparedness for the Voice of America 1 EXECUTIVE SUMMARY This report is an interim report, scheduled approximately halfway through the Committee’s study. It will be followed by a final report, due in 1989. Some of the study tasks, such as those dealing with DBS-A and emergency preparedness, are essentially complete. Consequently, this constitutes a final report on those efforts. However, a major study effort directed at antenna and propagation considerations is not yet complete and what is reported here is thus, by necessity, somewhat preliminary. SOME BACKGROUND The predecessor committee’s final report (National Research Council, 1986) made several recommendations intended to improve the Voice of America’s (VOA’s) technical and managerial position and result in a more efficient operation. Some of them have been implemented; some have not. The reasons for non- (or partial) implementation of those former recommendations are varied and in many cases outside VOA control; they include lack of a suitable staff or resources, lack of a clear mission direction from outside the VOA, and internal preoccupation with a technical upgrade program made chaotic by recent geopolitical changes and by recent and severe budgetary constraints imposed from without. Considering the situation as it existed two or three years ago and the problems that now exist, it is important to recognize that what was said then was predicated on the continuation of a strong, well-financed upgrade with staffing commensurate with the needs. This Committee is concerned about some of the recent negative press articles that quote from several reports, including that of the predecessor committee, now nearly two years old with much of it history. The present environment in which the VOA must operate is quite different from that of two to four years ago. Consequently, much of the recent criticism appearing in the media is based on statements and conditions that are no longer valid. It is, therefore, either off the mark or unfair. The Committee notes that VOA Engineering has, in the past, attempted to cope with a large increase in procurement authority imposed suddenly on

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Antennas, Satellite Broadcasting, and Emergency Preparedness for the Voice of America an agency with, at that time, negligible engineering resources. The predecessor committee watched the VOA engineering staff grow in size and competence, a process that does not happen in a day or a week, but over months and years. “Growing pains” are inevitable. Now, however, a relatively mature VOA Office of Engineering and Technical Operations has different problems and is trying to maintain its effectiveness in the midst of unforecast budgetary constraints. Therefore, some of the Committee’s conclusions and recommendations are, to varying degrees, outwardly directed—that is, directed towards other agencies and officials in a position to provide both knowledge and resources for the VOA to prepare for the future while conducting today’s business efficiently. The conclusions and recommendations presented here are abstracted or combined from those appearing in the detailed chapters that follow. Those that the Committee considers most important are summarized here; the others, treating problems of technical detail, are contained in the succeeding chapters. The interested reader should look there for more detail on technologically specific conclusions and recommendations. One recommendation, however, which was made in the predecessor committee’s report (National Research Council, 1986), is so important that the Committee believes it must be emphasized again. Even though it is not stated explicitly elsewhere in this report, it is unanimously arrived at from the Committee’s appreciation of the research and development (R&D) necessary to keep the VOA’s investment in new technlogy and systems current with the evolving state of the art. This matter is discussed in the following section, after which matters specific to this report are summarized. RESEARCH AND DEVELOPMENT AT THE VOICE OF AMERICA The VOA’s modernization program comprises a massive, capital replacement and new construction of terrestrial broadcasting facilities, and a first-time investment in modern systems networking of those facilities. Responsible management of such a massive investment in new technology carries with it a strong need for a continuing R&D program to ensure technical refreshment of the invested facilities so that they evolve with the technological state of the art and the need for another program like the current one is avoided. The predecessor committee’s report (National Research Council, 1986) made this recommendation in the form of an “analysis, experiment, and development (AED)” program; this Committee cannot emphasize strongly enough that such a program, whether it be called AED or R&D, is an essential part of any responsible, technical enterprise that has continuity. The VOA’s modernization program is just such an enterprise, and a very large one. Accordingly, the Committee arrives at the following recommendation: The research and development program of the Voice of America should be explicit and visible, not ad hoc.

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Antennas, Satellite Broadcasting, and Emergency Preparedness for the Voice of America The VOA’s engineering staff does conduct some ad hoc research and development, both in-house and out, under the aegis of advanced planning. They are to be commended for doing so, particularly during the present budgetary chaos. Nevertheless, the Committee continues to be apprehensive about the strength and viability of what remains an ad hoc approach. Some years ago, when the modernization program began, a frenetic staff buildup took place essentially in an information vacuum. Decisions had to be made and commitments undertaken in an environment with little available technological expertise and minimal planning. It was natural to expect mistakes and fortunate that there were so few of them. If the VOA had had a small, dedicated R&D staff operating throughout the “lean years”, much of the chaos of the rapid buildup might have been avoided. Plans would have been made and the technological expertise would have been in place to meet a need for modernization that had been well recognized for many years. As a result, the “wakeup” of the VOA would have been less tumultuous than it was. The Committee reiterates that the VOA should have an organizationally recognized research and development entity. Such a function should be isolated from the day-to-day modernization-program management but be available for technological consultation. Thus is innovation born and the future provided for. There are several ways to create such a function; the Committee will suggest one it deems most efficient: An organization the size of the Voice of America could benefit by having not only a Chief Engineer but also a Chief Scientist. A Chief Scientist’s position would not have direct line management, as does the Chief Engineer’s, but would have an advisory role and would report directly to the Director of the VOA. The staff to support such a person would not be large, but should support both high frequency (HF) and satellite broadcasting R&D. The Chief Scientist’s office would be concerned with the plannning and R&D necessary for the future missions of the VOA, including the currently primary topics of direct broadcasting by satellite and technology advances for HF broadcasting. In addition, that office might serve as the appropriate focus for activities related to World Administrative Radio Conferences. HIGH-FREQUENCY ANTENNAS AND PROPAGATION The topic of high-frequency antennas and propagation is a continuing one. Here, the Committee summarizes tentative and occasionally incomplete conclusions and recommendations, given in more detail in the second chapter of this report. Some of the recommendations of the predecessor committee have been implemented. Some have not. In some cases budgetary and programmatic changes beyond the control of VOA engineering were responsible for the lack of action. What is clear, however, is the growth that has taken place over the past three years—VOA Engineering is now a mature and relatively stable organization. The following paragraphs summarize the principal conclusions and recommendations bearing on HF antennas and propagation. Distributed antenna arrays, in which each sub-array (such as a row or

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Antennas, Satellite Broadcasting, and Emergency Preparedness for the Voice of America column of radiating elements), is driven by a separate power amplifier, need to be vigorously investigated, both theoretically and experimentally. In particular, the distributed transmitter, which might consist of a common modulator and power supply with multiple final amplifiers, needs to be developed. Thus the following recommendation is offered: The Voice of America should plan a program to investigate distributed transmitting arrays and distributed final amplifier transmitters. The new, delay-steered, high-gain, experimental transmitting array being completed at Delano, California, presents the VOA with an especially useful laboratory tool. In the process of evaluating the Delano array’s performance, new techniques for acceptance testing and performance monitoring of the next generation of VOA transmitting antennas can be developed. This observation leads to the following recommendation: The Voice of America should use the Delano array as a research and development tool. One such use would be to support an advanced-technology measurement study to develop techniques for verifying or improving the theory used in design of new HF antenna systems and to improve acceptance testing techniques for new antennas. One of the outcomes should be the generation of lower-cost acceptance testing methodologies; for example, discovering potential correlations between measured sky-wave patterns and such “ground-truth” data as element-current magnitudes and ground-level field strengths. The Committee commends the VOA for increasing the sophistication of its propagation modeling efforts. Nevertheless, the Committee continues to recommend that the propagation prediction tools known as IONCAP, IONSUM, and VALSUM be used with care. In particular, averaging should be applied, if at all, as late in the model-making process as possible. Furthermore, if at all practicable, data to be averaged should be stored for further study rather than eliminated. In addition, if experimental validations of the predictions are undertaken, for example by using data generated by the Delano array, these should be carried out on a propagation model with minimal averaging. Otherwise, the reasons for agreement with the observations may not be identifiable. At present VOA Engineering has no objective method of determining the strength of its signals, signal-to-(noise-plus-interference) ratios, or their correlation with signal quality in intended audience areas. The Committee urges that, together with the establishment of a backscatter monitoring program, the VOA undertake to develop such methods, and that they be automated. The committee offers the following recommendation: The Voice of America should establish a backscatter monitoring program. The program should include construction of a prototype

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Antennas, Satellite Broadcasting, and Emergency Preparedness for the Voice of America system derived from requirements that the agency develops for an operational system. Construction should take place preferably at a readily available U.S. site such as Delano, California, where the agency has recently installed a new, high-performance antenna. DIRECT BROADCASTING BY SATELLITE Direct broadcasting by satellite, a technology first developed and demonstrated by the United States, is technically and operationally mature and within the financial reach of governments, as shown by operational systems established for their countries by the governments of Japan, India, and the Arab states. This technology can provide a reliable, high-quality signal to earth receivers more effectively and economically than does HF. The technology of direct audio broadcasting by satellite (DBS-A) is mature, but there are certain steps the VOA should take to ensure that it is not left behind. In India, the Arab nations, and Japan demonstration experiments in satellite voice broadcasting are already going on in frequency bands internationally authorized for the Broadcasting Satellite Service by the International Telecommunication Union (ITU). In its final report (National Research Council, 1986) the predecessor committee recommended that the VOA seize the initiative of launching a cooperative experiment in DBS-A with India leading, making use of the operational Indian National Satellite (INSAT) for the purpose. This Committee reiterates that recommendation: The Voice of America should initiate contact with India promptly, while it develops a U.S. program in DBS-A. Such a program should include active participation in developing the U.S. delegation position for the forthcoming 1988 Space World Administrative Radio Conference of the International Telecommunication Union. The program should also include liaison with the receiver industry, both U.S. and foreign, to define the characteristics and economics of new DBS-A earth receivers. To these ends, the Director of the VOA should identify a senior professional, provide that professional a small staff and a moderate budget for both in-house and consultant assistance, and make that person and staff a focus for DBS-A planning, demonstrations, necessary SpaceWARC activities, and receiver industry liaison. This group should be part of the VOA’s R&D entity. Most importantly, since the DBS-A technology and concepts for large-scale, multi-use systems are operationally mature and financially realizable, the Committee urges the VOA to inform the White House, Congress, and the Administrator of the National Aeronautics and Space Administration of the opportunities for the future that it presents.

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Antennas, Satellite Broadcasting, and Emergency Preparedness for the Voice of America EMERGENCY PREPAREDNESS TELECOMMUNICATIONS The VOA, operating on a mission statement promulgated over a decade ago by Executive Order 11490, is tasked with the requirement to broadcast in the six primary United Nations languages (namely, English, French, Russian, Chinese, Spanish, and Arabic) during and after a major national emergency. As presented to the Committee, the mission is vague and ill-defined, with many associated, unanswered questions such as: To where? At what time? For what purpose? For how long a period (endurance)? Equipment? Energy resources—fuel, standby power, power from the power grid? Personnel resources? As a designated member of the National Communications System (NCS) and its Committee of Principals the United States Information Agency (USIA) has failed to participate. Thus, emergency preparedness guidance that it should have provided to the VOA has been completely absent. The VOA has conducted an ad hoc, part-time planning operation for emergency preparedness which has had all of the difficulties one would expect from a sideline effort, in spite of the dedication of those who have taken part (in many cases, on their own time). There is a clear need for a decision from the USIA leadership. Either the USIA should formally withdraw from its national security emergency preparedness role and not participate officially, or the USIA should acknowledge the requirement and, if there are staffing problems within the USIA, delegate the job to the VOA. Along with that delegation should come the funding necessary to support the activity. VOA’s own stake in this important activity leads to the following recommendations: The Voice of America should seek designation in its own right as a member of the Committee of Principals of the National Communications System, together with the authority to develop its own emergency preparedness telecommunications program consistent with national guidelines established by the National Communications System. The Voice of America should seek approval from the National Security Council for an up-to-date and sufficiently detailed mission statement for its operations during a national emergency. The mission and guidelines should provide for those steps necessary to achieve the endurability and survivability that do not currently exist within the VOA’s studio-to-transmitter link facilities or among VOA studios or in VOA provisions for staffing. It must be emphasized that, in real emergencies, power will be unavailable from the power grid. Furthermore, there should be an acknowledgment that endurability and survivability require budgetary decisions. The alternative of maintaining the status quo will result in inability to survive or operate through real emergencies because studio-to-transmitter links, and perhaps even studio capabilities themselves, would not have survived, and because emergency power will not be there to support VOA domestic telecommunications facilities.

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Antennas, Satellite Broadcasting, and Emergency Preparedness for the Voice of America REFERENCES National Research Council. 1986. Modern Audio Broadcasting for the Voice of America 1986–2001. Washington: National Academy Press.