For Broadcasters, Mobile DTV Emerges as Main Theme at NAB
I've been in Las Vegas since Monday working on a demonstration of mobile DTV transmitted over the Telemundo station KBLR and two synchronized transmitters (WD9XTL), one at the Stratosphere tower and the other at the Las Vegas Convention Center. It is only one of many mobile DTV demonstrations planned for this year's NAB Show.
This will be my 33rd consecutive NAB show. Looking back at past shows, some RF milestones stand out: the end of tube transmitters—except at high power UHF, where we saw klystrons, tetrodes and diacrodes give way to IOTs. More recently, NAB attendees had to look hard to find an analog TV transmitter on the floor.
This year I think we will see the start of a major change in over the air TV broadcasting. The number of over-the-air viewers has declined significantly in the last 33 years to the point that in most markets only a small percentage of viewers watch over-the-air TV on their home sets. While that trend may stall or even reverse as more consumers discover the benefits of free over-the-air TV, will there be enough viewers to make it worth the cost to maintain high power TV transmitters? The major technical advantage broadcasters have over cable and satellite providers is that their over-the-air signals can reach consumers without the need for special equipment, monthly fees or subscriptions. Turn on the TV and there it is. With the introduction of ATSC M/H technology, these programs will be delivered to consumers on their portable or mobile devices wherever they are.
Many major station groups and networks are members of the Open Mobile Video Coalition
. The large number of broadcasters transmitting mobile DTV for NAB and large number committed to starting DTV service in other markets has generated interest among consumer electronics and computer manufacturers. In a few years, when we look back on the 2009 NAB Show, it may be remembered as the year over-the-air TV moved out of the living room and into the pockets, purses and hands of a new generation of TV viewers.