Aggregator

re: Applications Accepted for Filing

.

Media Bureau designates as unreserved certain vacant FM allotments that are reserved for noncommercial educational ("NCE") use in various communities

LOS ANGELES — The Walt Disney Co.‘s fiscal first quarter of 2022 ended on January 1. How did the company do in its first three months of the fiscal year?

As CEO Bob Chapek sees it, “We’ve had a very strong start to the fiscal year.”

Thank Encanto and a rise in streaming portfolio subscriptions for that positive news. While the company’s linear networks saw lackluster results, investors approved of the overall results.

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He’s been with Beasley Media Group for the past 26 years and presently serves as the VP of Brand Strategies in addition to his role as a regional Operations Manager for two of the company’s radio markets.

Tee Gentry isn’t going anywhere anytime soon.

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A peculiar thing is happening to drivers of some Mazda’s operating in and around the Seattle area, and it could be caused by images displayed on dashboard screens.

Car owners are reporting their car radios are locking on 94.9 MHz leaving them unable to change the tuner. The only models affected are 2014–2017 Mazdas equipped with factory-installed HD Radios.

KUOW(FM) in Seattle, the NPR station that operates on 94.9 MHz, says it is hoping Mazda or Xperi can help. The radio station confirmed Tuesday on its website it is aware of the issue and has received complaints.

Mazda drivers have been complaining of the issue for several weeks, according to reviews of Reddit threads.

Some commenters on the discussion forum say the infotainment systems are “either locked up or constantly rebooting” and inevitably locking up on 94.9 MHz. Some drivers also have complained on the discussion board about not being able to make calls using the infotainment systems while driving.

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KUOW shared with Radio World a statement provided by Mazda after its dealerships in the Seattle area began receiving complaints from frustrated drivers about the problem.

“Between 1/24–1/31, a radio station in the Seattle area sent image files with no extension, which caused an issue on some 2014–2017 Mazda vehicles with older software. Mazda North American Operations (MNAO) has distributed service alerts advising dealers of the issue.”

Mazda continued: “While dealers are currently experiencing parts delays due to shipping constraints, MNAO will support impacted customers with replacement parts. These customers should contact their local Mazda dealer who can submit a goodwill request to the Mazda Warranty department on their behalf, order the parts, and schedule a free repair when the parts arrive.”

A KUOW spokesperson said the HD Radio system in the vehicles “pulls images from an NPR tool and uses the KUOW logo when there is nothing from NPR to use.” It’s unclear how widespread the problem is, according to the radio station.

Xperi, the developer of HD Radio, said its “assessment is that there was a formatting issue with the transmitted data.”

The company’s statement continued: “We have worked with the station to address it, and we do not believe there are any ongoing issues with car radios in the market.”

Some Mazda owners posting on Reddit theorize the images with no extensions likely corrupted lines of code in Mazda infotainment systems. “We have not received any information from Mazda on which specific file they believe triggered the issue,” the radio station spokesperson said.

Here is the statement KUOW posted on its website earlier this week:

“KUOW is aware of an apparent issue between our signal and some Mazda infotainment systems, causing radios to reboot when they connect to KUOW’s 94.9 FM signal. We have been in contact with Xperi, the company who owns the technology behind HD Radio, and have given them complete access to our transmitters to investigate what is causing this issue.

“Our operations team is doing everything they can to support them in finding a quick resolution. We also appreciate the assistance of listeners who helped alert KUOW to this issue and have provided additional information to aid the investigation.”

The post Radio Mystery for Some Seattle Mazda Owners appeared first on Radio World.

Updated at 12:50pm PT to include a comment from Xperi Corp.

On Sunday, January 30, an owner of a 2016 Mazda hatchback was driving in Ballard, Wash., when his in-dash entertainment system suddenly went awry. For some strange reason, the HD Radio his vehicle was equipped with would only play the main NPR member station for the Seattle-Tacoma market.

This driver wasn’t the only to experience the exact same problem. Is the glitch something every station equipped with the Xperi Corp.-owned product needs to be concerned about?

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Deadlines have been set to file comments in the latest NPRM from the Federal Communications Commission concerning emergency alerting.

As we’ve reported, the commission has a notice of proposed rulemaking that it says would improve the clarity and accessibility of visual Emergency Alert System messages to the public, particularly to people who are deaf or hard of hearing. In a companion NOI, the commission asks questions about broader measures to enhance the Emergency Alert System’s overall functionality and accessibility.

The NPRM presents proposals for modifying the text associated with national EAS messages, including pre-stored templates for NPT messages, and it proposes requiring “triggered” CAP polling.

The NOI asks, among many other questions, whether it would make sense to use legacy EAS only for the Emergency Action Notification (EAN) and NPT, but require use of CAP for all other alerts, and if legacy EAS can’t be reasonably modified to allow alert originators to distribute text to transcribe a two-minute audio message, whether the legacy EAS architecture should be redesigned altogether.

You can read Radio World’s recent story about the NPRM and NOI.

Now the deadlines are set. Comments on the NPRM are due March 11, and replies are due March 28. Comments on the NOI are due April 11 and replies by May 10.

Read the full proposal at https://tinyurl.com/rw-eas-4. File comments to the FCC at www.fcc.gov/ecfs/. To read others, enter 15-94 in the “Specify Proceeding” field.

The post Deadlines Are Set to Comment on EAS Changes appeared first on Radio World.

While the media industry has experienced its share of frustrations over the last two years, it has also seen one particular platform demonstrate steady, stable upward growth — despite the ongoing impact of the pandemic.

All in all, said Edison Research Senior Vice President Tom Webster, “It was an eventful year for podcasting.”

Edison Research recently announced its list of the top 50 podcasts of 2021. The list ranks podcasts by audience size based on the Podcast Consumer Tracking Report, a service that measures relative audience size and demographics of all podcast networks.

Last year the most popular genres were true crime, comedy and news programs, Webster said, although the list reveals a vibrant and diverse list of programming.

For the second year in a row “The Joe Rogan Experience” sits at the top of the list, a long-form interview and conversation podcast run by comedian Joe Rogan. The program recently made headlines when Neil Young and other musicians began demanding Spotify remove their music from the service due to Rogan and some of his guests’ promotion of misinformation about COVID-19. In addition, a video complication emerged of Rogan using an ethnic slur to describe the Black community. (Despite this, Spotify Technology CEO Daniel Ek said the platform would not cancel its $100 million licensing deal to be the exclusive host for the podcaster’s program archive, although some episodes have since been removed.)

The number two spot in 2021 belonged to The New York Times’ “The Daily,” a 20-minute weekday news roundup followed in the third spot by “Crime Junkie,” a weekly true crime podcast created by the Indianapolis media company audiochuck. Number four is “This American Life,” a weekly public radio program and podcast produced by NPR station WBEZ(FM). The top five is rounded out with the iHeartRadio program “The Stuff You Should Know,” focusing on obscure and captivating topics like how fortune cookies are made and how the game rock/paper/scissors became a decider of things.

A review of the networks on the top-50 list includes both well-known media sources and smaller media companies. iHeartRadio, The New York Times and NBC News sit in the top 10 as well as smaller media companies like audiochuck, Exactly Right and Earwolf. The top-50 list includes a few media networks with multiple popular podcasts, including NPR with its programs “Wait Wait … Don’t Tell Me,” “Planet Money,” “Up First” and several others. PRX is distributor for three top-50 podcasts, “TED Talks Daily,” “The Moth” and “Welcome to Night Vale,” while the Cumulus Podcast Network has two programs on the list, “The Dan Bongino Show” and “The Mark Levin Show.”

When compared to 2020 — the first year Edison Research began compiling and ranking U.S. podcast listening trends — the top four podcasts on the 2021 list exactly mirror the top four podcasts of 2020. The fifth place podcast in 2020 was “My Favorite Murder” by Exactly Right, which swapped places with “Stuff You Should Know” to drop to number six in 2021.

Investigative topics remained popular, including the serialized audio narrative and investigative journalism podcast “Serial,” along with true crime podcasts like “Criminal” and “Morbid: A True Crime Podcast.” Newcomers to the 2021 list include a twice-monthly weird fiction podcast focused on the imaginary town of Night Vale, a place rife with intriguing residents and conspiracy theories that has since spawned several books, albums and live shows. Other podcasts in 2020 that dropped off the list in 2021 include the design podcast “99% Invisible” and “Lore,” a podcast exploring the stories and people behind our strangest folk stories.

The top-50 list was compiled by Edison after gathering 8,000 online interviews with weekly podcast consumers in the U.S. aged 18 and older. The list tracks usage from the first quarter to the fourth quarter of 2021.

The full list is below.

The post Top 50 Podcasts of 2021 Court Crime, Comedy, Fiction appeared first on Radio World.

Telos Alliance has appointed Scott Stiefel as co-CEO, joining co-CEO Tom Swidarski to lead the company.

Frank Foti, Telos Alliance founder and executive chairman of the board, complimented Stiefel’s leadership skills and knowledge of both business and engineering.

In a company statement Foti noted, “Over the years, it’s been such a pleasure to see him grow, first as an engineer, then taking on the business segment.”

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Stiefel said he was “excited to join Tom in leading Telos through yet another era of growth and transformation.”

Stiefel’s career at Telos began in 1994, where he designed the ISDN card for the Telos Zephyr, worked on the original Omnia.FM and Audioactive Encoder products and served as project manager on the Zephyr Xstream.

In 2001, he moved from the engineering group to become operations manager for Telos, overseeing production, supply chain, logistics and quality.

After a six-year stint as vice president of operations at ViaSat, he returned to the Telos Alliance in 2014 and served as COO until this promotion.

Send news of engineering and executive personnel changes to radioworld@futurenet.com.

The post Scott Stiefel Appointed Co-CEO at Telos Alliance appeared first on Radio World.

“Against the high bar we set in our fiscal second quarter last year, we have once again delivered revenue and adjusted EBITDA growth in the second quarter of our 2022 fiscal year, while continuing to invest in our digital growth initiatives.”

Those are the words of Lachlan Murdoch, as the Executive Chair and CEO of Fox Corporation enjoyed a three-month period that saw net revenue and earnings per share each beat Wall Street forecasts.

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With the cancellation of NATPE Miami, originally scheduled for January 18-20 in Miami Beach, the National Association of Television Program Executives (NATPE) has moved forward with a slate of in-person and virtual events across the next several months.

Among them: a virtual February 17 “Station Group Summit” that, based on the agenda, is curiously devoid of the nation’s largest broadcast TV station ownership groups.

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WASHINGTON, D.C. — One week after a second nomination hearing for Gigi Sohn to serve as the FCC‘s fifth Commissioner was originally set to take place, the Counselor to former FCC Chairman Tom Wheeler appeared solo Wednesday morning in front of the Senate Commerce Committee.

While Sen. Maria Cantwell (D-Wash.) spoke warmly of Sohn, Republican members — led by its Ranking Member — came armed with questions for Sohn on two key topics. First, her ties to now-shuttered “vOTA” service Locast and the timing and monetary value of its settlement agreement with the “Big Four” networks needed further explanation. Second is her decision, after her first nomination hearing held in December 2021, to sit out on matters involving retransmission consent or TV broadcast copyright for the first three years of her term.

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NEW YORK — Local radio stations hit the jackpot with digital sales last year, generating $1.5 billion, according to the Radio Advertising Bureau’s 10th annual benchmarking report on the industry’s digital activities.

Stations are poised to follow last year’s growth of 33% with another strong year, with digital sales forecast to grow 22%, approaching the $2 billion mark.

“The radio industry seems to have finally found its digital groove,” the RAB report, compiled by Borrell Associates and sponsored by Marketron, notes. The 47-page analysis covers the activity of more than 3,000 radio stations.

“The findings from this report highlight the rewarded efforts of stations’ digital offerings to drive results for local advertisers,” said RAB President/CEO Erica Farber. “The focus on the importance of digital training has produced dividends for stations and sellers alike. RAB continues to provide business and professional development training that will help stations to super-serve their local businesses.”

For Gordon Borrell, he was happy to report that Borrell Associates underestimated radio’s digital determination when last year’s report was published. He comments, “We predicted that radio would hit a double by increasing sales 18%. They hit a triple – maybe even a home run. It’s quite impressive, especially when you see that little stat that shows how digitally savvy radio sales reps are in the eyes of local advertisers.”

The annual report showed that the average station made $362,250 in digital revenue in 2021, and the average market cluster made $1.6 million.

Top-performing market clusters made more than $10 million, even in some of the smaller markets.

“The local radio salesperson is now the marketing expert in their community by bringing linear and digital solutions to advertisers that produce real, measurable results,” said Todd Kalman, SVP/Sales at Marketron. “In this report, you’ll find data and insights that position radio and digital together for new advertising opportunities in 2022.”

The findings are a part of the RAB and Borrell’s 10th annual report, “Finally, A Digital Bounty: Radio’s Digital Sales Rise 33%,” released today to RAB members. It analyzes online ad revenue from 3,645 radio stations, as well as survey responses from 1,107 local radio buyers and 256 radio managers.

Among the findings:

• Advertisers now rate radio sellers higher than all competitors for marketing expertise.

• Advertisers now rate radio sellers on par with or higher than competitors for digital expertise.

• Nearly one in four station managers now deem their digital strategy “brilliant.”

• Eighty-eight percent of radio advertisers buy digital advertising, but only 46% buy it from their radio rep.

• Twice as many stations as last year say online-only reps are the best way to drive more sales.

• Virtual events didn’t stick in 2021; only 13% of stations are planning them this year.

• While 44% of stations have a local podcast, only 20% have one that produces revenue.

He’s made it clear that his media enterprise plans to invest approximately $10 billion to acquire more ABC, CBS, NBC, and FOX television stations over the next two years with the goal of creating the largest broadcast television group in America.

Now, Byron Allen may be taking a page from Jeff Smulyan’s playbook by confirming his interest in owning a professional sports franchise.

The revelation also notes that it was the Commissioner of the National Football League, and New England Patriots owner Robert Kraft, who suggested to Allen three years ago that he consider the investment.

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Zachary Sinutko (left) and Collin Kennedy in the WJCU studio at John Carroll University

It’s the radio interview that went on and on …. and on. And that’s a good thing.

On Feb. 5 and 6, 2022, two DJs at WJCU(FM) on the campus of John Carroll University broke the Guinness World Record for longest consecutive radio interview.

The program started at 7 am on Feb. 5 and ran live until 8:35 a.m. the next morning, capping a 25-hour, 35-minute-long interview. The program aired on 88.7 FM in Cleveland, on Instagram Live, via the WJCU radio app and on Twitch.

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The record-breaking event was led by two radio staff — Zachary Sinutko and Collin Kennedy — who serve as on-air personalities as well as executive producer and co-producer, respectively, of the station’s hip-hop/rap show “808s and Mixtapes.”

“It was so much fun and college radio is my life,” said Sinutko, who is also director of promotions and events at the station. “Doing this was a dream of mine for a long time.”

Ahead of the attempt, Sinutko expressed confidence in their ability to break the previous record. “Two college students + a ton of energy drinks and a passion for college radio = countless possibilities,” he stated on the station’s website.

The previous record was set by Bhanu Bhakta Niraula on Nov. 8, 2021, at Himal FM 90.2 MHz in Kathmandu, Nepal, with a 25-hour, 26-minute-long interview of Nepalese tourism expert Ang Phinjo Sherpa.

Sinutko said official auditors were present at the event at WJCU, which broke the previous record by nine minutes.

“It got hard in the middle of the night but with the help of the community and the rest of the university, we did it,” said Kennedy. “Thank you to the school and to everyone who passed by the WJCU studio to help encourage us to do the unachievable.”

WJCU is a noncommercial FM broadcast station owned and operated by John Carroll University with studio and transmitter facilities located on the JCU campus in University Heights, Ohio. The station operates on a non-stop schedule with an effective radiated power of 2.5 kW at 88.7 MHz.

Submit news about your station to radioworld@futurenet.com.

The post College Radio Station Sets Guinness World Record appeared first on Radio World.

Radio World Engineering Extra is a deep-dive special edition of Radio World that comes six times a year and is edited by award-winning engineer Cris Alexander.

In this issue, John Schadler of Dielectric writes about why the FCC should allow computational modeling of directional FM antennas. And Andreas Hillebrand and Bill Rounopoulos discuss global remote production using Ravenna/AES67 and Amazon Web Services.

Read it here.

The post Inside the Feb. 9, 2022 Issue of RW Engineering Extra appeared first on Radio World.

The author is vice president of engineering, Dielectric LLC. This article is based on a paper prepared for the NAB Broadcast Engineering and IT Conference of the NAB Show and is published with permission. Proceedings of the conference are available at https://nabpilot.org/beitc-proceedings/.

Abstract: There are approximately 900 Class A directional FM stations licensed in the United States. Many reasons exist to directionalize an FM antenna, including maximizing signal coverage over a designated market area (DMA), reducing lost signal over unpopulated areas, shaping the pattern to fit within the station’s authorized footprint and conforming to the rules stated in Title 47 CFR 73.316.

Currently, applications proposing the use of directional antenna systems must include a tabulation of the antenna pattern through measurements performed on a test range of either full scale or 4.4:1 scaled model setup.

It has been requested that the FCC acknowledge that the public interest will be served by the commission accepting computational modeling of directional FM antennas in lieu of physical measurements of antenna characteristics and/or performance for purposes of applications and licensing.

Products such as Ansys HFSS are 3D electromagnetic (EM) simulation software tools for designing, simulating and evaluating high-frequency electronic products such as antennas, antenna arrays and RF or microwave components. The use of 3D high-frequency simulation will in many ways yield results that are superior to traditional range measurement proofs, in terms of accuracy.

Since simulations are done in a true free-space environment, any issues with the range or anechoic chamber and with the surrounding environment are eliminated, resulting in more reliable azimuth patterns and H/V ratio.

The use of software also eliminates the lengthy setup and take down time of models as well as the need for a technician to adjust the model and take data points by hand, thus removing mechanical tolerances and human error affecting the data.

Another advantage of designing in a virtual environment is that the geometry can be completely optimized and not compromised by time, materials and tolerances.

This paper will go into detail on the many benefits illustrating why the FCC should authorize the use of 3D high-frequency simulation computer modeling to demonstrate that a directional FM antenna performs as authorized.

Introduction
The rule for licensing of FM directional antennas is found in §73.316(c)(2) and §73.316(c)(2)(iii) of Part 47 of the Code of Federal Regulations. It states that applications for license upon completion of the antenna construction must include a tabulation of the measured relative field pattern.

Read literally, since it asks for a tabulation of the measured relative field pattern upon completion of antenna construction, this language would seem to imply that an FM antenna must be measured after installation, through field measurements of the installed antenna, which can be quite impractical to make and would have been more so at the time that the rule was adopted in 1963.

Consequently, we assume that the rule was interpreted initially to require that FM directional antennas be measured on full-size test ranges, since such ranges were available then for characterizing both the azimuth and elevation patterns of broadcast television antennas.

In 1976, Matti Siukola, RCA scientist and unit manager of advanced development for RCA Broadcast Systems, presented his paper “Pattern Optimization of FM Antennas” at the NAB symposium.

Siukola proposed parasitic elements to be used as directors or reflectors in either horizontal or vertical positions to directionalize a simple FM antenna. In the same paper, Siukola also proposed the more economical use of scale modeling.

It has now been 45 years and basically nothing has changed regarding FM broadcast pattern verification. Interestingly, characterization of azimuth patterns has evolved in all other broadcast services such as AM radio and television.

The commission has a history of accepting computer modeling
The procedures required or allowed by the FCC for characterization of antenna azimuth patterns vary quite markedly between broadcast services: AM radio, FM radio and television.

It is notable that, while the rules for directional antennas for FM and TV were similar at their initial publication in 1963, there were a few significant differences between them that have led to different procedures over the years.

The most significant difference between the two approaches to directional antenna rules was that the FM rules required a “means (such as a rotatable reference antenna) whereby the operational antenna pattern will be determined prior to licensed operation and maintained within proper tolerances thereafter,” while the TV rules had no such requirement.

So, while the FM rules required a method for producing a “proof of performance” on the antenna prior to its use and for its maintenance over time thereafter, the TV rules did not.

The main difference between the two sets of 1963 rules is that the FM rules require that measured pattern performance data for a directional antenna be submitted as part of the application for a license to cover the corresponding construction permit once the antenna has been installed. The current TV rules (including the DTV rules) only require pattern data for a construction permit and don’t define whether that data must be derived through measurements or can be the product of calculations. The real-world results of this rule difference are that directional TV antennas and their patterns are specified almost exclusively using calculations, which, over time, have migrated to computational modeling of the antennas.

When comparing the three fundamental broadcast services and the treatment of their directional antennas in the commission’s rules, the AM antenna rules were updated over a decade ago.

In 2008, use of the Method of Moments (MoM) computer modeling, based on the Numerical Electromagnetic Code (NEC), was permitted as pattern verification for AM services. This approach provides considerable savings in time and cost for antenna manufacturers and ultimately for the broadcasters who purchase the antennas.

As discussed above, the TV/DTV rules already are flexible enough to permit use of computer modeling both for the design of antenna patterns and for the testing of the antenna’s performance without the need for physical models. That leaves only directional antennas for FM broadcasting with the requirements and burdens of having to go through the steps of first building models of antennas, measuring those models and collecting the related data.

RF Computer Modeling Outside the Broadcast Industry
Not only has the commission approved software modeling for AM directional antenna array proof of performance, but it has approved proof of performance for medical devices and RF radiation exposure evaluation of portable devices as well.

The high level of accuracy that simulation software provides has allowed a wide range of RF device manufacturers to significantly reduce the cost and time associated with proof of performance to the commission.

Computer Modeling — Repack
The timeline of the broadcast repack created a unique situation in the industry. Since many broadcasters needed new antennas and RF systems in a short amount of time, creative engineering solutions to reduce lead time had to be found.

The adoption of 3D high-frequency simulation to gather impedance, phase and amplitude data allowed for expedient antenna design and eliminated many limitations. This process has been successfully used at Dielectric to design more than 1,000 antennas since the beginning of the repack.

In addition, electrical design time was reduced from several weeks to less than three days. The manufacturing space needed to store physical models and house anechoic chambers has been repurposed to further accommodate manufacturing needs. This process has proven to produce more accurate designs, which is evident in the reduction of test time needed to bring the full antenna into specification.

It is safe to say that, without the use of virtual simulation, it would have been essentially impossible to design, manufacture, test and install the nearly 1,000 antennas that had to be replaced to complete the Post-Incentive Auction Spectrum Repack in the minimal time allowed for the process.

Fig. 1: DCR-Q Quadrupole FM-style antenna designed and manufactured for Channel 3 during the repack.

It is worthy to note that, in the television spectrum repack, as some TV stations moved from UHF to Low-VHF, they needed new directional Low-VHF antennas. In several cases, the designs used were those of FM directional antennas scaled to be larger, to work at the lower frequencies of TV Channels 2.6.

Because they were to be licensed for use by TV stations, the new Low-VHF antennas could be developed and proved with all the latest computer modeling techniques for design, manufacturing and testing. Had those very same antenna designs and patterns been constructed for the purpose of use a few MHz higher, in the FM band, only because of the differences in the FCC rules, it would have been necessary to physically model them prior to building them and to physically measure them to collect data for submission to the FCC during the licensing process.

Fig. 1 shows a quadrupole ring antenna typically used for FM broadcast design for the use at TV Channel 3.

Range Measurement Accuracy
An important part of range antenna pattern measurements is the alignment and reflectivity of the range. Alignment typically relies on mechanical bore sighting with the assumption that the antenna used to transmit the signal to the device under test (DUT) is perfectly electrically aligned. Alignment accuracy is therefore limited by both mechanical and electrical constraints.

The principle reason for the pattern to deviate from what would be expected from an idealized range are reflections from the range surface, surrounding objects, the positioner and the cables used to feed the antenna. Sometimes signals from external sources also pose a problem. The field at a point in the aperture under test is the phasor sum of the test signal and the extraneous signals. The relative amplitudes and phases of the desired and extraneous signals will vary with position along the test aperture causing constructive and destructive additions, thus producing a measured pattern that will depart from the free space expected pattern. (See “National Association of Broadcasters Handbook, 11th Edition,” 2018. Chapter 10.8, “VHF and UHF Television Antenna Test Range Measurements,” John L. Schadler.)

Fig. 2: Range measurement error.

Range measurement accuracy limitations are removed with the use of computer simulation.

Mechanical Tolerancing and Human Error With Physical Modeling
Software eliminates lengthy setup and take down of models as well as the need for a technician to be physically present to adjust the model and take data points by hand. Accuracy is improved greatly using simulation as it removes mechanical tolerances and human error affecting the data. Information that is traditionally recorded by hand, such as radiator location and parasitic sizes and locations in space is replaced by a simple exportation of the computer model. The full three-dimensional model can be sent directly to 3D CAD software for detailed component manufacturing and installation instructions, eliminating the possibility of documentation error and physical measurement inaccuracies.

Automated Optimization
Another advantage of designing in a virtual environment is that the geometry can be completely optimized and not compromised by time, materials and tolerances. Variables can be automatically adjusted, and complete data tables exported for the next step in the design process. This is done through an artificial intelligence. An optimetric setup can simultaneously solve any combination of pattern shapers, parasitics and radiators positions in space to find best fit solutions. Trial and error techniques traditionally used to develop the geometry necessary to produce a desired pattern is replaced by this artificial intelligence optimetric process. Criteria are set based on the desired azimuth and FCC regulation and multiple antenna configurations can be run in parallel to reduce overall study time.

Significance of Polarization Ratio
The rules under 47 C.F.R. §73.316 state that the supplemental vertically polarized effective radiated power (ERP) required for circular or elliptical polarization shall in no event exceed the effective radiated power authorized.

Since in most cases, broadcasters consider the vertically polarized component more important than the horizontal and tend to maximize their vertical signal, accurate polarization measurements are important.

Range measuring the polarization ratio at any point in space with accuracy is difficult. Since no range is completely free of reflection and the fact that horizontal and vertically polarized waves reflect differently, the accuracy in the ratio is limited by the range reflectivity. Polarization ratio range measurement accuracy is also limited by the transmit antennas horizontal and vertical polarization pattern congruency.

If the transmit antenna is linearly polarized and is spun from horizontal to vertical for polarization tests on the DUT, the assumption is that the beam is perfectly straight and has no wobble. If separate radiation paths are used to measure the polarizations, such as switching between crossed dipoles, the assumption is that each of the patterns and gains of the two paths are identical.

Each of these sources for error is eliminated with the use of 3D high-frequency simulation.

Comparison of Physical Model Measurements and Computational Simulation
To show the validity of computer modeling in place of physical modeling of FM directional antennas, an example design using both methods, i.e., physical modeling and computational modeling of the same antenna, are compared.

Fig. 4: A 4.4:1 scaled model antenna test.

In the example design, a directional pattern study for Station WHEM, 91.3 MHz, Eau Clair, Wis., was performed on a scale model FM test range using a scaling factor of 4.4:1 for all elements involved in the study.

The scaled elements included a model of an antenna bay and identically scaled models of parasitic elements and the mounting pipe to be used by the station. All the scaled model components were rotated through 360 degrees while receiving a signal at the appropriately-scaled frequency from a linear cavity-backed source antenna.

The horizontally and vertically polarized azimuth patterns were measured in an anechoic chamber test range. The signal source and scale-model antennas were mounted at identical elevations and at opposite ends of the test chamber. A network analyzer was used to supply the RF signal to the source antenna at 4.4 times the fundamental FM frequency (i.e., at 401.72 MHz) and to receive the signal intercepted by the antenna under test.

A photograph of the scale-model pattern study configuration is shown in Fig. 4.

Fig. 5: HFSS model used for simulation.

This directional pattern study was replicated in the Ansys HFSS environment using the full-scale CAD model of this antenna bay, mounting pipe and parasitics at the fundamental frequency of 91.3 MHz six years later. See Fig. 5.

The original results of the scaled model directional pattern study were accepted by the customer and demonstrated both proof of performance and FCC pattern envelope compliance in both the horizontal and vertical planes. A statistical measure of the relationship between two sets of data can be analyzed using the correlation coefficient (r). A correlation coefficient of r = 1.0 represents a perfect match. It can be used as the figure of merit to determine how closely the range measurements match the HFSS calculations.

Where:
xi = x values in sample
x̅ = mean of the x value samples
yi = y values in sample
y̅ = mean of the y value samples

Fig. 6 displays the overlaid horizontal and vertical polarization patterns and the FCC pattern mask. As can be seen, the results of the Ansys HFSS directional pattern study very closely match the results of the scaled model study.

The horizontal polarization azimuth pattern for both the scaled model study and the simulated pattern study have a maximum deviation of 1.67 dB and a minimum deviation of –1.39 dB compared to the scaled model study. The correlation coefficient for the horizontal polarization is 0.986 and 0.960 for the vertical polarization. The figure also shows that the computationally simulated antenna exceeds the FCC pattern mask in the vertical polarization pattern by a minimal amount. It must be noted that if computer modeling was used in 2015 at the time of this study, modifications would have been made to bring the vertical component inside the FCC protect.

Fig. 6: A 4.4:1 scale model physical testing vs. HFSS simulation.

Conclusion
The tools that were available when the current rules for FM directional antennas were developed in 1963 only included full-size or scaled modeling of antennas, combined with physical measurements, to approximate the characteristics that would be obtained when an antenna was installed.

In the decades since then, computational methods have evolved to enable more accurate and precise predictions of the antenna performance. The FCC has for decades relied upon manufacturers of FM directional antennas with engineering personnel who can apply the necessary skills to design and test broadcast antennas. The basic knowledge, experience and expertise requirements with respect to antenna design and modeling remain the same when the newer computational modeling techniques are applied as was the case prior to their availability.

It therefore stands to reason that the manufacturers of FM directional antennas should be permitted to apply the new tools at their discretion and that the FCC should accept the results of computational modeling as being just as valid as the results from physical construction and measurement of either full-size or scaled models of antennas.

A special thank you to S. Merrill Weiss, president of Merrill Weiss Group LLC, for his contributions to this topic. He is responsible for the writing and submission of the Petition for Rule Making to the FCC, “Computational Modeling of FM Directional Antennas.” Portions of this paper are based on that work.

The post Allow Computational Modeling of Directional FM Antennas appeared first on Radio World.

There’s a new effort afoot to develop a guideline for the use of metadata that accompanies audio streamed by radio stations.

The National Radio Systems Committee is a technical standards-setting body co-sponsored by the National Association of Broadcasters, representing the transmission side of the radio broadcast industry, and the Consumer Technology Association, representing the reception side.

The NRSC’s Metadata and Streaming Work Group, or MSWG, has a new chair, consultant David Bialik of David K. Bialik & Associates, succeeding Alan Jurison. That working group is part of a larger Data Services and Metadata Subcommittee, or DSM, chaired by Steve Shultis, CTO of New York Public Radio.

Bialik, whose articles about streaming and work at the AES are familiar to Radio World readers, will be responsible for leading development of NRSC-G304, a guideline for streaming audio metadata.

“David’s expertise in the area of streaming for broadcast audio will be put to good use as the new chair,” Shultis said in the announcement. “Radio broadcasters rely increasingly upon their audio streams and the NRSC is eager to help develop better standards in this area.”

The planned document is a guideline for radio broadcasters describing how to use metadata on the streaming audio versions of radio broadcast programs, Bialik told me.

“It focuses on the HTTP live streaming (HLS) method of audio streaming as this has become a de facto standard within the radio broadcasting industry.”

People who are interested in participating in this work should email David Layer at dlayer@nab.org.

Comment on this or any article. Write to radioworld@futurenet.com.

The post Audio Streaming Metadata is in the Spotlight appeared first on Radio World.

Working age adults who report to a jobsite or office outside the home are highly essential for the continued success of broadcast radio.

How so? They use radio more than two times as much as those who work from home, newly released data from NuVoodoo Media Services show.

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