Of all the functions performed by radiocommunications, none is more familiar to the general public than broadcasting. Indeed , to the layman, the term "radio" is synonymous with audio broadcasting. Radio and television broadcasts provide entertainment, information, and educational services to nearly every household in America. Both forms of broadcasting are accommodated primarily in the broadcasting, and more recently the broadcasting-satellite services.[EN308]
While broadcasting is among the most familiar services, it is also among the most rapidly changing. New services, including high definition television (HDTV), digital audio broadcasting, and new direct broadcast satellite (DBS) services will augment, and in some cases compete with, existing AM and FM radio, VHF and UHF television, and TVRO.
The results of WARC-92 will have considerable influence on the broadcasting services for many years to come. Additional radio spectrum was allocated for broadcast systems, including satellite systems to provide HDTV and audio broadcasting with compact disc (CD) sound quality.[EN309] Also, an additional 790 kHz of HF spectrum was allocated for broadcasting, including a new band between 18,900 and 19,020 kHz that will be available in the year 2007.[EN310]
The application of the broadcasting service in the United States is used to serve both international and domestic audiences. International audiences are served by Federal and non-Federal international broadcasting stations.[EN311] Domestic U.S. audiences are served by commercial over-the-air radio and television systems which continue to be the major source of local news, sports, public affairs, etc.[EN312]
International broadcasting by its very nature requires the generation of signals that are intended to be transmitted across international borders. Consequently, transmission of these signals is subject to the ITU Radio Regulations. For decades, governments have made increasing use of the electromagnetic spectrum to conduct public diplomacy by broadcasting speech and music throughout the world. These broadcasts are made directly to receivers used by individuals throughout the world.
The Voice of America (VOA) of the United States Information Agency (USIA) is the Federal agency that is assigned the mission of preparing and broadcasting radio programs related to U.S. interests and activities.[EN315] The VOA transmits audio programs to audiences in English and 43 other languages throughout the world.[EN316] VOA's transmissions originate in the studio complex at VOA headquarters in Washington, DC. Unlike the non-Federal international broadcaster, VOA uses two terrestrially-based radio broadcasting technologies in the United States to reach its international audiences: HF and AM radio.[EN317]
VOA has three HF transmitting stations in the United States located at Greenville, North Carolina; Bethany, Ohio; and Delano, California. VOA is the only U.S. Federal foreign broadcast service that operates from the United States. Radio Free Europe (RFE) and Radio Liberty (RL), funded by Congress through the Board for International Broadcasting (BIB), serve as surrogate stations for the countries to which they broadcast: Eastern European countries (for RFE) and the former Soviet Union (for RL).[EN318]
In the United States, domestic audiences are served by AM, FM, and TV broadcast stations employing analog radio transmissions designed for direct reception. The U.S. domestic broadcasting structure is a complex, interconnected web of over-the-air radio and television stations, intertwined with cable and satellite delivery media carrying programming by numerous competing sources. U.S. households are well served with 99 percent owning a radio (5.6 radios average) and 98 percent owning television sets (average of 2.1 sets).[EN319] Over one-third of the TV households can receive 7-10 TV channels and over another third can receive 11-14 TV channels.[EN320] However, more than 61 percent of U.S. TV households subscribe to cable television[EN321] and over 70 percent of U.S. television households own VCR's. [EN322] Planned service include improved terrestrial and satellite broadcast systems.
AM broadcast stations are licensed by the FCC for operation on a channel in the 535-1705 kHz AM broadcast band. This band consists of 117 carrier frequencies beginning at 540 kHz and progresses in 10 kHz steps to 1700 kHz.[EN323] The modulation of the radio carrier wave is amplitude modulation; hence, the AM reference. Depending on the broadcast station class, maximum operating power ranges from .25 kilowatts to 50 kilowatts.[EN324] Propagation in the AM broadcast band involves both the ground wave and skywave modes. The ground wave and skywave modes of AM broadcasting stations serve local and distant audiences, respectively. A disadvantage in AM broadcasting is its limited audio fidelity, relative to FM.[EN325] There are over 4900 AM broadcast stations operating in the US&P.[EN326]
The potential exists for an enhancement to the U.S. AM broadcast operations with the introduction of digital audio broadcasting technology, where the audio fidelity is expected at or near CD-quality. Various terrestrial digital audio broadcasting technologies are being developed worldwide. In the United States, two different terrestrial digital audio broadcasting technologies are being considered but only the "in-band" technology can be implemented in the AM broadcast band.[EN327] This is a promising new service that must consider technical and marketplace forces to succeed. Under the auspices of the Electronic Industries Association (EIA) and the National Radio Systems Committee (NRSC), efforts are presently underway to evaluate and recommend an in-band on-channel (IBOC) system for AM broadcast operations.
FM broadcast stations are authorized for operation on 100 allocated channels, each 200-kHz wide, extending consecutively from Channel 201 on 88.1 MHz to Channel 300 on 107.9 MHz.[EN328] Depending on its FM station class, the maximum effective radiated power authorized ranges from 6 kilowatts to 100 kilowatts.[EN329] Over 6700 licensed commercial and noncommercial educational FM stations are supported in this band: 5109 FM commercial stations and 1733 FM educational stations.[EN330] Better audio fidelity is a distinct advantage of FM radio over AM radio broadcasting; however, FM radio does not normally have the extensive service coverage areas that AM radio broadcasting enjoys.
As with the AM broadcast stations, IBOC technology represents a potential enhancement to FM broadcast operations. Two IBOC proponents with a total of three FM IBOC systems are presently being evaluated under the auspices of the EIA and NRSC.
Advances in microelectronics, digital signal processing, and video compression technology have recently brought advanced television (ATV) technologies close to commercial application in the United States.[EN333] Digital HDTV is an ATV technology and would provide improved picture (high resolution, better color, and wider screen) as well as improved sound (at or near CD) quality.[EN334] The FCC, through a rulemaking proceeding, proposed to provide an ATV channel for each television broadcast station and require simulcasting on both the NTSC and ATV channels.[EN335]
Despite the development of satellite program delivery systems, commenters indicated that there continues to be a long-term shortfall of allocated HF frequencies for international broadcasting operations.[EN336] Both Herald Broadcasting and the National Association of Shortwave Broadcasters (NASB) urged that the difference between the amount of spectrum recommended by the Industry Advisory Committee and what was provided by WARC-92 should be used as a basis for future planning by the United States.[EN337] This shortfall amounted to approximately 1,655 kHz. VOA indicated that less than half of the VOA's HF frequency requirements were included in the U.S. proposals to WARC-92.[EN338] VOA identified its unsatisfied spectrum requirement as the shortfall from what it identified in its requirements process to what was allocated by WARC-92.[EN339] This was calculated to be approximately 1,810 kHz. These two requirements contain common spectrum and cannot be added directly. Considering the overlapping requirements, the total additional spectrum requirement is approximately 1,900 kHz. There are a number of radio services still competing for allocations in the limited HF spectrum. These include, in addition to international broadcast operations, the fixed, mobile, and amateur services.
The National Association of Broadcasters (NAB) indicated that most broadcasters in the United States favored a terrestrial IBOC technology and that there appears to be significant progress being made towards this end with recent demonstrations of prototypes in the AM and FM broadcast bands.[EN340] The NAB also noted that should IBOC digital audio broadcasting not achieve technological success and not succeed in adequate U.S. market penetration, an additional 54 MHz of spectrum would be required to implement "out-of-band" digital audio broadcasting.[EN341] General Motors recognized the promise and uncertainties of in-band digital audio broadcasting technologies and indicated that the United States should be prepared to introduce a competitive digital audio broadcasting service should in-band digital audio broadcasting prove to be unsatisfactory.[EN342]
The NAB indicated that no new additional spectrum would be required to implement ATV since ATV channels would use spectrum provided from existing UHF TV channels as envisioned in the pending FCC ATV rulemaking proceeding.[EN343] Members of NTIA's Spectrum Planning and Policy Advisory Committee noted that there is an uncertainty regarding whether or not ATV can be fully accommodated in the UHF TV band noting that the FCC draft ATV Table of Allotments includes the use of VHF channels for 17 ATV allotments.[EN344]
Developments in digital coding, modulation, and compression have made the transmission of digital audio commonplace and digital video feasible. These technologies are gradually making their way into the conventional broadcasting scene as digital audio and ATV. The potential exists for an enhancement to AM and FM broadcast stations where the sound quality can equal or nearly equal that of CD-technology. Also, HDTV is being developed in the United States, Europe, and Japan as a means of providing greatly improved picture quality to television viewers. The U.S. development of a successful HDTV system will provide the basis for revolutionary new video services to many homes, industry, scientific, and medical customers, as well as affecting billions of dollars of international trade. The U.S. capability in digital signal processing and video compression technology is creating the first digital HDTV standard that could displace existing Japanese and European analog technology.[EN345] The implementation of HDTV may be difficult and expensive for broadcasters, but it appears essential for broadcasters to find a way to upgrade their facilities to provide HDTV to consumers and remain competitive with the virtually certain introduction of HDTV by cable, VCR's, and DBS. International broadcast stations will experience improved spectrum efficiency with the planned single-sideband implementation and with satellite-sound broadcasting potentially representing a supplemental delivery system to international audiences.
From the comments received and information collected, we believe that no additional spectrum is required for terrestrial AM, FM, and TV broadcast services. Efforts to develop and implement IBOC digital audio broadcasting technology in the AM and FM broadcast bands appears promising and, if successful, no additional spectrum would be required. The FCC plan to facilitate development and implementation of ATV does not appear to require additional spectrum. Eventually, the spectrum vacated by the transition from the VHF channels to UHF channels will free up some, if not all, of the 72 MHz of VHF TV spectrum. Federal and non-Federal broadcasters expressed their requirements for additional HF spectrum as the shortfall resulting from WARC-92. The aggregate U.S. requirement for additional HF broadcasting spectrum was calculated to be approximately 1,900 kHz, since these separate requirements were not mutually exclusive. However, strong competition for the limited and very congested HF spectrum continues from the maritime, fixed, mobile, aeronautical and amateur services.
In the 1970's and 1980's, satellites became a chief means of long distance radiocommunication and facilitated worldwide TV program distribution in real time and, in some cases, with delays as required due to time zone differences. In rural areas not serviced by terrestrial TV broadcast stations and cable TV systems, FSS satellite signals made possible direct reception of TV from satellites by TVRO receivers equipped with parabolic antennas with diameters between 2 and 5 meters. For almost two decades, TV program delivery by satellites was done in the 4/6 GHz and 11/14 GHz FSS bands.[EN346]
Developments in advanced radiocommunications technologies and the offer of improved radio-based services paved the way for direct TV and audio broadcasts from satellites. Today, three technologies have been aggressively developed for the BSS: the direct broadcast service (DBS), BSS-HDTV, and BSS-Sound. The frequencies for the DBS uplink, sometimes referred to as feeder link (Earth-to-space direction), are allocated in the FSS.[EN347] Downlink DBS frequencies are allocated in the BSS.
With the launching of the first U.S. DBS in late 1993 and its operation in mid-1994, another means for the delivery of conventional television programming directly to the consumer was achieved. This application marked the first U.S. broadcasting use of 12.2-12.7 GHz for the BSS. A few companies were expected to begin service in 1994 and others have active plans to launch DBS service. DBS systems are commercially used in Europe and in Japan.
Relative to FSS satellites that deliver television programming, U.S. DBS satellite systems use higher-powered transponders. TV receiver antennas are dishes approximately 0.5 meter in diameter, and incorporate new, state-of-the-art delivery technology. Their use of advanced satellite antennas make efficient use of available satellite power and frequency spectrum with their spot beam-type of antennas. DBS receiver hardware is small, inexpensive, and easy to install.
Some HDTV proponents began to develop satellite systems and pushed for new international allocations for satellite-delivered HDTV at the 1988 and 1992 WARC's. Initially, many believed more allocations were necessary due to the large transmission bandwidths required by analog HDTV technology, and that it would not be accommodated into the channels planned for the BSS.[EN348] The U.S. proposal for a single worldwide BSS-HDTV allocation at the WARC-92 was not supported; however, the conference adopted two BSS-HDTV allocations: Region 2 at 17.3-17.8 GHz; and Regions 1 and 3 at 21.4-22.0 GHz. These new allocations will become effective April 1, 2007.[EN349]
Another technology that is aggressively being developed is the broadcast satellite delivery of high-quality audio programming (BSS-Sound). BSS-Sound generally refers to the delivery of music, sports, news, etc., directly to consumers' radio via satellite. WARC-92 adopted three different allocations for BSS-Sound: 1452-1492 MHz, 2310-2360 MHz, and 2535-2655 MHz.[EN350] The FCC has allocated the spectrum 2310-2360 MHz based on the international allocation adopted for the United States by the WARC-92 for a Digital Audio Radio Service (DARS).[EN351]
Presently, there are no operational BSS-Sound systems in the United States; however, systems are now under development that will employ digital technology to broadcast CD-quality programming to consumers. Consumers will receive radio programming via their mobile or portable radios and be able to receive the program signals across the United States. Such services will not be compatible with existing analog AM and FM radios and require consumers to purchase new radios to enjoy this new broadcast service. The DARS, as envisioned, will be provided via satellites for wide area coverage and be supplemented, as needed, by terrestrial stations for local services or to fill in areas where the satellite signal is marginal.
Satellite broadcasting systems appear to be helping the United States move into a dual approach in providing television and radio programming services to the U.S. consumer. DBS will help bring direct-to-the-home television programming and possibly HDTV in the very near future. BSS-Sound will help bring additional audio listening choices to the American consumer.
Commenters believed that the spectrum allocated for DBS at 12.2-12.7 GHz is adequate[EN352] and that it is unlikely that the requirements of the DBS will ever saturate this band.[EN353] The NAB pointed out that while DBS systems are now being developed by several proponents, public acceptance and demand for this technology will not be known for some time.[EN354] Hubbard believes, despite the WARC-92 actions, that a single worldwide allocation for the DBS should have been made instead of being split into two separate bands.[EN355] Further, Hubbard believes that technology will make it possible to accommodate HDTV by DBS at 12.2-12.7 GHz and that the bands at 17.3-17.8 GHz should be regarded as "expansion" bands should the 12 GHz band become saturated.[EN356] Satellite CD Radio, Inc. stated that the 2310-2360 MHz band will be sufficient to allow for competitive entry by the four DARS proponents.[EN357] The NASB does not believe that satellite-based broadcasting will represent a replacement for HF broadcasting any time in the foreseeable future. However, they believe it could supplement HF broadcasting.[EN358]
From the comments received and information reviewed, we believe that no additional spectrum is required for the DBS, BSS-HDTV, and BSS-Sound in the foreseeable future. We expect future requirements for BSS feeder links to be accommodated in existing FSS bands and that the currently allocated spectrum to be adequate.