HD Radio: FM-HD
"IBOC Digital AM and FM Technology Launch"
2002 - "In terms of coverage, the answer is it replicates the existing analog coverage, and that is all it can do. Not technically, but because of a regulatory reason. We could easily boost the IBOC power, but guess what, then that steps on the station next door... Bob Struble, CEO iBiquity Digital Corp."
"More About IBOC"
"Through the performance of comprehensive channel characterizations, conducting countless simulations using real world data and logging over 75,000 hours of over-the-air tests on numerous radio stations, iBiquity Digital designed its IBOC technology to bring the benefits of digital audio broadcasting to today's radio while preventing interference to the host analog station and stations on adjacent channels."
"Rhode Island Public Radio”
"It was apparent to me that the purpose of Greater Media's and iBiquity's presence was not to promote accurate, real-world results, but instead to minimize any evidence of actual interference to the analog signal of a first adjacent station."
"Asymmetrical IBOC: Upgrading HD Radio Power"
"It’s about asymmetrical IBOC. The only real advantage IBOC transmission has had so far is its relative immunity to multipath. But that immunity is the result of the redundancy of data in the upper and lower first-adjacent channels. Without that redundancy, IBOC will be less immune to multipath than either the double-sideband suppressed carrier analog stereo difference signal or an SCA signal — whether that SCA is a conventional analog narrowband FM signal or a digital FM Extra signal. So in any additional area covered by only a single IBOC signal, there will be no multipath advantage."
"Jonathan E. Hardis"
"I document that the Order is based on significant errors of fact and false statements, and that it was adopted without the requisite public comment on the most significant data upon which it is based. Even more remarkable is that it was adopted in clear contravention of the Commission’s rules."
"Response To HD Power Boost Disappointing"
"FCC Media Bureau Audio Division Chief Peter Doyle said at the Future of Music Coalition's Policy Summit this week in Washington, DC, that only about 150 stations have notified the FCC of their interest in increasing power for their HD Radio signals."
"Others Challenge Blanket Increase"
"Press Communications filed an Application for Review and Request for Stay, citing an unalterably biased outcome of the proceeding based on testing conducted by the parties who had a stake in the outcome, without a full technical review or independent verification. NPR had already admitted to vast amounts of new interference, wrote Press. The NAB is somewhat tainted with a majority of its Executive Board and eight to ten others on its Radio Board having invested money in the venture. Meanwhile, a member of its radio board with a heavy investment in HD equipment in its group largely conducted the tests on its own stations working directly with iBiquity."
"Oh Well, on With the Experiment..."
"The saga continues. It’s remarkable that the development of the IBOC system began well over 20 years ago, yet it still seems to be an ongoing experiment... In their 2008 report, they warned of dire consequences that would ensue from a blanket FM IBOC power increase. They had plenty of statistics to back this up, derived from studies of numerous stations, using sophisticated propagation prediction tools. According to these results, there were some significant interference problems even at the existing –20 dBc power level. But then another study is hastily done, and now we’re told: Oops, our mistake, a blanket increase of 6 dB is actually just fine, and even a 10 dB increase will be okay in most cases."
"FCC OKs Increase in HD Radio Power"
"In effect, this high bar will serve to only bolster the appearance that HD radio does not cause interference because it will be too costly to demonstrate it according to the Media Bureau’s satisfaction, not because listeners aren’t actually experiencing degraded analog radio reception... At this point it will be up to non-HD stations and affected listeners to band together if they have any hope of seeing digital power increases limited or eliminated. However, this seems pretty unlikely to occur, especially amongst listeners."
"Comments of Barry D. McLarnon, P. Eng."
"In short, these results prove little or nothing, and no further results of any consequence have been presented by iBiquity. This is typical of the subterfuge and lack of critical analysis that has been a characteristic of the IBOC system since its early days. It is worth noting that iBiquity and other IBOC proponents had an opportunity to respond to my critique of their test methodology in Reply Comments, but none of them did so."
"New Jersey Broadcasters Association"
"The Commission rejected the pleas of the more ubiquitous analog Class 'A' FMs over 20 years ago, who begged for a meager (3db) power increase to do exactly what HD Radio now prays for; that is, to increase coverage and building penetration. Absent a suspension of reality or a disingenuous application of reason, why should the IBAC stations' request now be granted at the unjustifiable expense of the remaining 80+% of analog FMs that have faithfully served their communities and proven their vitality through the immutable test of time. It is not only inequitable, it is dangerous."
"IBOC Interference"
"I’ve already had situations where a local, non-IBOC station’s signal is quite listenable, but an HD Radio-equipped radio will be taken over by a co-channel (same frequency) station that is running HD Radio from a hundred miles away! This will force listeners with HD Radios to lock them in analog mode, something some of the new radios are not even capable of, even if the clueless consumer would have any idea how to do it in the first place. The radio has no idea that the IBOC carriers are not in any way connected with the analog station the consumer is trying to listen to. This is a basic, fundamental flaw in the HD Radio system that will cause all kinds of grief in the future if IBOC power levels are increased, and the radios are in greater circulation."