HD ENG adds to long list of challenges for convention frequency coordinator
Aug 5, 2008 8:00 AM
That means that some broadcasters will have to shift channels from the ones they have been using that week. But it is a big deal if they don’t go to the correct one. Logistically, we have to make sure that everyone really understands, and it’s almost like a rehearsal. We’ve cut in a two-hour window from noon to two on Thursday to do testing. But it isn’t like testing that we are doing in Denver and in St. Paul, where we have two days of testing in three hours and three hours. The INVESCO test is a two-hour test, and it will occur as everything else is happening, so there may be bands playing as opposed to the other tests where we can control the venue; this two-hour test will be a very, very big challenge to make sure we do things right.
Frankly, there is very little room for error. If there are interference issues, and we determine that at two o’clock on Thursday, in some cases, there’s not much we can do about it.
HD Technology Update: You sent FCC Chairman Kevin Martin a letter recommending that the two conventions presented an opportunity to test prototype white space devices under consideration for use in the TV spectrum white spaces? What was your thinking behind the offer?
Louis Libin: We are moving into a new world, and there are a lot of claims being made about white spaces and white space equipment — claims that it will be able to do so many things and that it will be able to operate without any type of interference and be able to be interoperable with all of the systems that we have.
I really decided that the political conventions are the best possible scenarios, since we are dealing with the largest event where we have all different types of wireless equipment in the wireless mic bands.
HD Technology Update: How do you propose using the conventions as a venue to test these prototype white space devices?
Louis Libin: We would try to do it at first during the first two full days of testing — three hours and three hours. One would be on Wednesday prior to the convention, and the other will be on Sunday.
The tests are actually very interesting. You turn things on in an order. The cells are working with QUALCOMM on their channel 55 with the MediaFLO, and somebody is always by the switch if we have an interference problem to shut it down. The white space equipment would operate under very, very similar constraints.
After everything is up, we’d turn on the white space devices and see what happens. Then we would turn off some wireless mics and turn them back on, and let’s see if this new technology is able to do what it says.
HD Technology Update: Have you heard back from the chairman about the offer you made in your July 9 letter recommending the tests?
Louis Libin: No, not yet.
HD Technology Update: How much lead time do you need before the conventions to prepare for the white space device tests?
Louis Libin: We’d want to put it into the schedule, so we’d probably need not much more than a week prior to the testing.
HD Technology Update: Have other wireless technologies that have proliferated over the past several years presented interference challenges at live broadcast productions?
Louis Libin: We are constantly moving toward new equipment and new challenges. But in most cases, we have been able to deal nicely with them.
A typical example would be that there is a lot of 802.11 in the 2.4GHz spectrum that’s right next to the channels that we use for the cameras. Sometimes when, for example, you go to a golf event where the golf courses are completely surrounded by residential areas, you’re looking at the noise floor in that 2.4GHz spectrum that is very, very high, which impacts some of the 2.5GHz and some of the 2.3GHz, if we are using something like that.
In that respect, you have to be careful and you have to figure out what changes are. But we are also able to do different things. This time, for the first time at a political convention, we’ll be using wireless mics in the 1.4GHz band, which is a COFDM band, and we’ll be cutting out chunks of 2MHz for 10 wireless mics. So we are able to test and we are able to figure out what the interference characteristics will be. It will have the same modulation type, but we don’t really know. It’s always a challenge to figure out how things will operate once we turn on.
HD Technology Update: Is there anything else you’d like to add about the conventions, interference or preparations?
Louis Libin: We are trying to be very organized. We’re trying to make sure we won’t do any coordination, except for equipment failure, on the days of the convention. This is the first time we are trying to do this.
There are so few channels that we are able to use that we want to make sure everything is tested and signed and sealed beforehand. That’s really the big challenge, and if we’re able to do that then we have a good plan and we will have been able to implement it.
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