Post on 07-Feb-2016
description
transcript
No, your presenters are not “drinking the iBiquity Kool-Aid”
Practical Operations Concerns about HD Radio
Aaron Read (WEOS, Geneva)
An “engineering-lite” look at the issues and concerns surrounding digital broadcast solutions like
HD RadioTM
What is HD Radio?Hint: the “HD” doesn’t stand for anything!
Digital broadcasting by iBiquity Corp. IBOC = In Band / On Channel Backwards compatible All-digital someday, maybe. Bennies: Better audio quality, data services,
PAD/PSD, multicasting
HD Radio: Hybrid Mode
Analog radios ignore digital (white noise)
HD Radios = analog > buffer > blendSeven second delay
Lost digital = blend backMulticast = mute
HD Radio: Kibbles and bits
AM HD = 36kbps hybrid / 40-60 digital FM HD = 96-120kbps hybrid / 300 digital Based on the HDC (AAC) codec It’s all just bits, so partitioning is
possible. Using the bits for things other than audio also possible.
Must my station install HD Radio?
No FCC mandate (unlike DTV)Market-driven adoption
Will your listeners support it?Promotion, sales, installation
Only HD Radio is NRSC-approvedTheoretically, others could do it
HD Radio’s benefits: FM & AM
Audio fidelity (not quality)AM = FM, FM = CD (sort of)(20kHz)
No multipath PSD / PAD Data: iTunes Tagging, conditional access,
downloads, etc Multicasting! (FM only)
HD Radio’s problems: FM & AM
Algorithm is lossyAM makes mess of bandRequires good engineeringNot cheap ($75k - $200k?)Getting in over your head
HD Radio’s problems: AM only
Overall, not really recommendedAdjacent-channel interferenceSelf-interferenceDifficulty with Dir. ArraysNighttime problems w/skywaveVery low adoption by broadcasters
HD Radio’s problems: License Fees
Different way of thinking! iBiquity has steep one-time feesMulticasting have add’l fees
$1k/yr or % of revenueData service also have add’l fees
HD Radio -20dBc vs -10dBc
Standard HD was -20dBc (1/100th)Deemed not enough by NAB or NPR
FCC authorized blanket -14dBcUp to -10dBc in some situationsCan require much bigger xmitters
What about our FM antenna?
Short answer: it dependsHi-level combining
Inefficient, but equal patternsSeparate/Interleaved
Redundant, efficient, but pattern problems & weight/wind load
Changing Perceptions
Breaks the “norms” Digital = ON or OFF, not gradual fade in/out
like analogNO FRINGE COVERAGE
Old worries = multipath, stereo hiss, not loud enough
New worries = cascading algorithms, pre-processing, listener perceptions
Upgrading your technical plant
May need a lot of new $$$$ gear!STL – bursty data, extra channelsMonitoring – delays and multicastAudio Storage – cascading algosProcessing & PreprocessingArbitron PPM explosionExtra webcasts, websites….staff?HD is a computer – lifecycle?
Upgrading your schema
Adding multicast is like adding whole new stations!Extra studios, processors, monitoring,
access, audio gear, computers, program sources, staff?
24 hours/day to 72 hours/dayCan you handle the workload???
HD Radio benefits
Multicasting – streamline format, appeal to new listeners
Fill untapped niches – earn more revenue
Potential leasing = more revenue
Thinking outside the box
Rent out your HD2/HD3 for profit Got a translator? HD2 on it! Only Part 15? Rent another HD2
Pay for install, get free rent Unusual formats
The ten minute loopJazz, classical, foreign-language…?
Future thinking on HD Radio
No FCC mandate, but listeners might! Costs are high = long term planning
needed!Probably longer than you’ll be there
New studio facility may be a must = long-term investment/planning
Shameless Self-PromotionThe IBOC Handbook : Understanding HD RadioTM Technology
Looking to really learn the engineering of IBOC / HD Radio? Read this book! First Overview of the Approved
NRSC-5 (IBOC) Standard. Authored by David Maxson Illustrated by Aaron Read
Available on Amazon.com
Final Thoughts
Questions – and please no: Rants, Screeds, Diatribes, Harangues, Raving, Tirades,
Bullyragging, Vociferation, Bloviating, Railing, Objurgating, Badgering, Molestation, Nettling, Ruffling, Badgering, Pestering, Heckling or Persecution.
Tell us your situation, we’ll opine if HD Radio is right for you!
Aaron Read can be reached via www.friedbagels.com/blog Need an engineer? www.sbe.org