Working closely with equipment distributor and system integrator Hannu-Pro, Grass Valley engineers have competed installation of numerous signal processing and distribution products and systems at the Latvia State Radio and Television Center (LVRTC) in Riga to facilitate Latvia’s nationwide switch from analog to digital transmission via a DVB-T single frequency network (SFN).
Hannu-Pro started the first phase of project in August 2009 and completed system testing in December. As of this month, the first national DVB-T multiplex (and additional two multiplexes from Lattelecom) is available over the air to 95 percent of the Latvian population.
Now that the first phase is complete, a second phase will see the deployment of four additional DVB-T multiplexes. Thus by 2012‚ when the country’s DVB-T service introduction will be finished, there will be seven DVB-T multiplexes available in Latvia, all based on headend technology from Grass Valley. All essential systems are designed to support full redundancy (1+1 or n+1), ensuring on-air reliability.
The LVRTC is the technical DVB-T service provider for Lattelecom, the largest telco in Latvia. The company is overseeing the nationwide deployment of DVB-T equipment to facilitate terrestrial broadcasts of radio and television signals that cover the entire territory of Latvia.
In the country’s central broadcast station (headend) in Riga, Grass Valley ViBE SD MPEG-4 encoders and NetProcessor systems prepare the signals for transmission to the LVRTC’s regional centers (via an SDH network). The headend will also provide the required SFN adaptation. Seven regional centers have installed ViBE encoders for compression of regional programs and NetProcessor systems for program and ad splicing.
The DVB-T system infrastructure will incorporate numerous NetProcessor network adapters to pass the signal to DVB-T transmitters; ViBE MPEG-4 decoders to support decoding to PAL and analog TV reception during the transition period; an XMS network management system, which provides network administration and is configured to support redundancy operations.
The XMS system is integrated with a Granite Sentinel monitoring system, for uninterrupted monitoring and compliance to the DVB-T standard (TR-101290) for the signals received from Lattelecom and ASI signals on multiplexer outputs. It also controls RF parameters (COFDM) before signals are passed on to the RF antennas. In addition, an electronic program guide (EPG) is being supplied by a Grass Valley Jade system.
