RF CURRENT

NAB stated that "This is not and never has been a 'marketplace transition.'" and offered these recommendations: "Specifically, the FCC should (1) adopt a procedure ... for processing the backlog of DTV applications and for resolving mutual exclusivities, (2) must mandate inter-operatability and other and other technical standards, (3) must adopt DTV must carry rules, (4) must require DTV receiver performance standards and (5) must require DTV tuners in every new television receiver sold."

NAB referred to a study of broadcasters' problems with DTV implementation, saying, "It is clear from our survey that government inaction can become a real barrier to a smooth and timely digital build-out. Because of the very large numbers of stations yet to build DTV facilities, it is imperative that the Commission take affirmative steps to facilitate local and federal approval processes for the approximately 1,472 stations schedule[d] to make the transition to digital television in the next 24-36 months."

NAB did not enter into the COFDM versus 8-VSB modulation standard debate.

CEA also warned of the consequences of considering another standard: "Based on the facts we discussion herein, it is crystal clear that the DTV Standard should be re-affirmed. Consideration of any non-compatible changes for DTV would create needless delay and marketplace confusion, disadvantaging those who have worked the hardest to attain the FCC's goals and undermining the certainty that is necessary for rapid deployment of DTV products and services. ...The marketplace disruption that would be occasioned by Commission consideration of any inconsistent alteration or change without broad industry consensus would, at a minimum, delay the DTV rollout substantially."

CEA quoted a study showing 50 percent DTV product penetration by 2006 if broadcasters meet the FCC's rollout deadlines and provide a high percentage of digitally originated content to consumers, including HDTV. However, CEA said, if broadcasters follow non-high definition business models and advocate reopening modulation standards issues, DTV product penetration will be only 15 percent by 2006.

Joint Broadcasters offered a method for resolving mutually exclusive DTV maximization requests. Broadcasters warned, quot;...granting all applications regardless of interference in areas beyond initially allotted DTV service areas is not a viable solution. The Commission would be abdicating its responsibility to oversee the application process and to bring order to the transition to DTV. As a practical matter, the granting of all applications likely would result in mutually destructive interference to the public's service, in which substantial service areas of two or more stations would be compromised. Moreover, the impermissible interference would not be simply between conflicting applicants but could affect a 'victim' station; two or more applicants could push another station above the 10 percent cumulative interference limit." It also said the FCC was prohibited by the Communications Act of 1934, as amended, from using spectrum auctions to resolve mutual exclusivities. Joint Broadcasters suggested that, "Once mutual exclusivities are identified, our proposal provides for a negotiation/mediation period followed by a period to amend applications, which in turn would be followed by dismissal of all MX applications that are not revised to reduce interference to comply with the de minimis allowance or are not accompanied by interference agreements (whether arrived at by negotiation or mediation)."

Joint Broadcasters commented DTV receivers: "The transition to DTV will not succeed if consumers cannot make receiver purchases confident that they will be able to receive signals over the air and watch a consistently high-quality picture. Equipment manufacturers have the responsibility to produce receivers that perform well and meet consumer expectations. However, manufacturers are not producing many sets capable of over-the-air reception at all, and what receivers are produced do not meet customer expectations, particularly where there are dynamic multipath conditions. ...Even second generation DTV receivers, although improved, are still at least two generations away from maximizing the potential of the 8-VSB transmission standard."

Joint Broadcasters noted the need for receiver performance standards as well as the need to evaluate the 8-VSB system itself, saying, "Broadcasters have a role, along with the Commission, in establishing receiver performance thresholds and verifying that our DTV transmission system is sufficiently robust and flexible. To perform that role, a group of broadcasters, including many of the undersigned, undertook in early April a six-month investigation and test program of DTV reception. The objectives of this program are (1) to press for, support and test improvements in VSB performance, and (2) to develop and implement a two-phase plan to test COFDM systems for application in the United States. Regardless of what these studies show, we believe that now is the time for the Commission to adopt receiver performance thresholds."

Joint Broadcasters criticized consumer electronics manufacturers, stating:

"So far, equipment manufacturers generally have not risen to the challenge. Only 17 percent of all DTV sets sold to date are capable of receiving over-the-air DTV signals at all. And many of the receivers that are built to receive DTV signals have shown inadequate tuner performance. Furthermore, many of these receivers perform poorly in challenging RF environments."

"Receivers have not only performed badly in distinguishing among interfering signals at the edge of the service area, but they have performed inadequately in acquiring signals in the core of the service area under multipath and other challenging RF conditions. It is simply unacceptable from a public interest standpoint to wait for the market (the small market for DTV receivers) to remedy these performance shortfalls. The Commission should now step in to correct the market failure and mandate minimum desired-to-undesired signal performance thresholds."

"There is no alternative to mandatory performance thresholds for instilling confidence in consumers that the DTV receivers they purchase will be able to display a consistent picture from over-the-air signals. Given the failure of equipment manufacturers to produce acceptably functioning receivers, it is the Commission's responsibility to ensure that they do. Moreover, in order to avoid further delay, the thresholds that the Commission establishes should become effective twelve months from the date of this proceeding's Report and Order. Broadcasters will work with the Commission to supply the conclusions of the industry's 8-VSB performance testing to assist in the creation of an adequate performance benchmark."

Responding to concerns this would delay the DTV transition, ALTV said, "...we see no reason why FCC review of COFDM transmission capabilities should in any way delay the roll out of digital television. The key herei s not to delay the roll out, but to be prepared should the 8-VSB performance standards falter, either for technical or political reasons. We view this approach as a safety net which will avoid even further delays in the future. Significantly, ALTV is not asking the FCC to substitute COFDM for 8-VSB. Moreover, we are not asking for a dual standard at this point in time. Instead we are simply asking the FCC to be prepared."

Public Television's comments also supported "active Commission involvement in ensuring the quality of DTV receivers." Public Television urged the FCC to delay a requirement for stations to make a final DTV channel election, opposed new uses for TV channels 3, 4 and 6, and asked the FCC not to impose a DTV replication requirement now.

Public Television recommended a DTV maximization application processing procedure different from that proposed by Joint Broadcasters. Public Television suggested, "...processing the pool of applications filed before the cut-off date by granting all checklist, non-checklist, and maximization applications that do not seek to cause interference beyond a station's allotment parameters..." The comments also said, "Public Television stations with out-of-core DTV and NTSC channel[s] should be permitted to defer construction of their DTV facilities."

ATSC recommended some changes to the DTV standard, affecting the audio bit rate and Program and System Information Protocol (PSIP). It also said, "the Commission should ensure that 'major channel numbers' are used properly and that the assignment of 'TSID' parameters is properly administered."

NxtWave's comments offer information on NxtWave chip performance and copies of several published technical articles describe the approaches NxtWave is taking to improve 8-VSB equalizer and receiver performance. NxtWave claims its second-generation chip is capable of correcting a 0 dB echo.

NxtWave pointed to how technology once thought impossible is now commonplace today to support its argument that the improvements in the receiver design would allow 8-VSB to support broadcasters' requirements for reliable TV reception: "The equalizer architecture, spare-allocation algorithm, and hardware implementation of the NXT2000 are modified in the NxtWave second-generation chip for substantially improved indoor reception. NxtWave engineers also have developed, and continue to develop, advanced architectures and algorithms that will be economically realizable in 0.18 micron silicon. This trend is analogous to the 5-year old 300 baud modem that has evolved into today's 56 kilobaud standard, as predicted by Moore's Law."

Motorola, however, urged the FCC to avoid mandating EIA-708, section 9 as the exclusive standard for closed captioning, noting that digital cable programming services all use the DVS-157 format to carry EIA-608 captioning.

As an example of the progress it has made, Philips outlined its tests with the "Harbor Channel" case, named for a location "that produces particularly severe multipath interference." Philips said its third generation chip "will, in fact, be able to receive a signal in the Harbor Channel."

Philips raised the same concerns as others that reconsideration of the DTV standard's modulation scheme would lead to disruption and delays in the DTV transition. It also argued against receiver standards and noted the transition would benefit from more HDTV programming.

"First, the utility of terrestrial broadcasting in the digital age can be maximized only if the underlying technology permits mobile and portable applications. As it now exists, 8-VSB would foreclose development of many new applications and services because it cannot viably support mobile or portable services. As a result, the unique potential of terrestrial DTV might never be fulfilled in a delivery system that relies exclusively on 8-VSB modulation as it currently exists. Industry is now working to address certain shortcomings of 8-VSB, including multipath performance. The Commission should monitor the progress of these efforts to ensure that industry continues to cooperate to improve modulation technology so that it supports a wide array of devices and services, including those that are portable and mobile.

"Second, the pace of technological innovation continues to be rapid. To enable DTV technology to advance and develop as fully as possible, the Commission should work to ensure that technical solutions for standards are as flexible and unrestrictive as possible to maximize the potential for innovation."

Microsoft urged the Commission to "investigate whether 8-VSB can support (or be modified to support) mobile and/or portable applications. If it appears unlikely that 8-VSB can reliably support mobile or portable applications, the Commission should analyze other options to ensure that such DTV applications reach fruition. In addition, given ATSC 8-VSB's forever-frozen data rate of 19.39 Mbps and the absence of hierarchical modulation capability, it appears that 8-VSB for the foreseeable future will not permit the provision of the portable video services that are available today in the NTSC environment."

Microsoft did not see a problem considering other modulation standards, saying, "Moreover, there is no material risk to conducting a thorough evaluation of other technologies. Many of these technologies, such as COFDM, have already been widely tested and continue to be developed and improved. Conducting additional interference studies could be completed in under a year. Further, as the Sinclair petition demonstrated, there is significant support for COFDM among some terrestrial broadcasters. Because COFDM could be added as an option to 8-VSB rather than a replacement, the Commission may wish to consider its possible adoption in addition to 8-VSB."

Sinclair also rejected arguments that allowing use of COFDM would delay the DTV transition, decrease coverage and increase receiver costs, stating:"...Sinclair believes that if the Commission decided to permit U.S. broadcasters to operate using the COFDM-based DVB-T standard, implementation of that standard as an alternative to ATSC 8-VSB would likely take little more than a year. Certainly, the initiation of such a regulatory process would bear a smaller risk of meaningful delay than continued reliance on the unsubtantiated and speculative claims of receiver and chipset manufacturers."

With regards to the 2 dB difference in C/N performance for COFDM and its effect on coverage, Sinclair explained, "...this 2 dB difference does not lead to any material difference in the receivability of the 8-VSB and COFDM signals. ...For the very small percentage of TV households at the Grade B fringe that may be unable to obtain high-quality COFDM reception, such reception could be ensured through the purchase and deployment of a preamplifier, which typically costs between $10 and $20. In contrast, there is no reasonable technological solution for the urban viewer whose location suffers from multipath distortion."

Sinclair answered the cost issue by saying it "believes that the cost incurred by receiver manufacturers from a dual-mode standard would be marginal. The DTV receivers sold today in the U.S. market are already configured to receive signals with multiple modulation modes -- these receivers are typically designed to receive signals from DBS systems, cable systems, NTSC, and 8-VSB broadcasters." Sinclair noted there are more than half a million COFDM receivers in service in the U.K. and Europe, 15 times the number of 8-VSB receivers sold in the U.S. over an almost identical period. Sinclair added that other services such as DARS, MMDS, DBS and PCS have been allowed to use multiple standards.

Sinclair said the FCC should listen to broadcasters, rather than equipment and chipset manufacturers as it addresses the 8-VSB reception problem.

Fox departed from the comments of some other broadcast groups and indicated it supported the FCC's propose requiring NTSC replication and requirements for minimu field strength over a DTV station's principal community. However, it agreed with other broadcaster comments urging a delay in establishing a deadline for stations to make a DTV channel election. Regarding mutually exclusive DTV maximization applications, "Fox advocates that mutually exclusive DTV maximization applications should be processed on a first come/first served basis as is currently the procedure for all other broadcast services. ...Fox submits that seemingly mutually exclusive DTV maximization applications should be evaluated with both stations assumed to be maximized, because often the increased power of both stations will cancel out enough interference so that both applications will fall within de minimis interference benchmarks."

iBlast commented, "iBlast is concerned that any change in the DTV standard would inevitably result in delayed DTV implimentation as it would necessitate extensive study and debate of the many engineering issues surrounding system implemention, receiver design and frequency allocation. ...It is well know that the competing technical approaches to digital signal modulation and propagation -- 8-VSB and COFDM -- have inherent strengths and weaknesses. ..it has been well documented that the 8-VSB standard exhibits fundamental advantages in signal strength, payload capacity and transient noise immunity. Trading away these advantages appears to us to be ill advised. ...in adopting an alternative modulation standard, such as COFDM, we would simply trade one set of imperfections for another."