Belar To Demo Automatic Delay Correction At NAB

Belar Electronics is to host a series of Automatic Delay Correction demos at NAB 2015, Booth C2452. The demos will highlight the deployment options of Belar's HD Radio diversity delay/time alignment solution, in partnership with a number of industry brands, including GatesAir, Nautel and Wheatstone.

Belar's Automatic Delay Correction software provides a way to eliminate delay between digital and analog signals in the blending areas of HD Radio coverage. The software measures the FM/HD time alignment, and controls the roughly eight-second delay between HD and analog FM programming to ensure a pleasant listening experience. The demos will show how Belar's software delivers this task without forcing users to push the audio through the modulation monitor. Instead, the Automatic Delay Correction feeds the adjustment back toward the front of the air chain, with corrections taking place in the audio processor, HD exporter, or standalone precision delay line.

"High-end audio processors today from companies like Wheatstone, Omnia and Orban typically include a delay line, or can integrate one through software updates," said Belar CEO Mark Grant. "However, those with well-functioning older high-end processors, or other less feature-rich processors, typically do not have or cannot integrate a delay line. In these cases, companies like GatesAir and Nautel offer an especially valuable service via connectivity with their HD exporters."

Tim Anderson, manager, radio market and product development at GatesAir, has said its demo – Booth C3107 – will unveil how flaws in the HD Radio system architecture, network timing issues and synchronization cause continual drift or sudden shifts in otherwise perfectly aligned installations – and how the GatesAir/Belar integration automatically detects, correlates and corrects misalignments at regular intervals to improve listener experience.

"Using the latest Belar FMHD-1 modulation monitor and its Automatic Delay Correction software with GatesAir's HDE-200 Exporter control protocol, the analog-to-digital diversity delay timing is constantly monitored and correlated to generate a correction message," said Anderson. "That message is sent via Ethernet to the GatesAir HDE-200 Program Exporter's internal diversity delay control, and the correction is applied and continually maintained within optimum specifications, assuring that the FM and HD audio streams are always synchronized."

Visitors to NAB 2015 can also view Nautel's demonstration of its exporter and the FMHD-1 at Booth C2131.

On the processing side, Wheatstone (Booth C755) will demonstrate how corrective timing is able to take place in its AirAura, FM-55 and other audio processors without broadcasters having to insert another box into the air chain.

Belar's ADC algorithm is introduced into the audio processors through Wheatstone's network protocol Automatic Control Interface (ACI). Belar's algorithm in the FMHD-1 continuously measures FM/HD time alignment and transmits closed-loop diversity delay corrections back to the Wheatstone on-air processor through the ACI interface.

"Every HD Radio broadcaster has a diversity delay in the program line, and many customers utilize the one built into our on-air processors," said Jeff Keith, senior product design engineer at Wheatstone. "By not modifying the existing air chain, we can keep the signal path pure and simply tell the processor what the perfect diversity delay setting should be. Because all of our on-air processors already have the ACI protocol built in, a simple software upgrade opens up access to the HD diversity delay being controlled by the Belar FMHD-1."

Grant added that, while not being demonstrated at the show, Belar also integrates 25-Seven's Precision Delay and Orban audio processors. It is also working with Omnia to integrate Automatic Delay Correction into their latest-generation on-air processors.

Photo: Wheatstone's AirAura

www.belar.com

(JP)