White Space Testing Postponed
Washington, DC (October 29, 2007)
On Friday, October 5th, the FCC issued a public notice announcing that further testing of new proposed "White Spaces" devices will continue at an undisclosed date. The edict, which effectively rescinded a self-imposed deadline made by the Commission promising that new White Spaces regulations would be revealed later in the same month, gives a second chance to companies including Microsoft, Dell, Intel, and Philips to secure a place within TV bandwidths for a new generation of portable, spectrum-seeking communications devices.
This "do-over", if you will, comes on the heels of the FCC's first White Spaces interference studies, which demonstrated in July that prototype devices submitted for testing by Microsoft and Philips failed to detect both wireless microphone operations and DTV channels, and caused interference with the transmissions of both. Claiming that the testing was flawed, and that one of the devices was malfunctioning, Microsoft and Philips pressed for further testing.
Now, with more trials on the horizon, it still remains to be seen what exactly is in store for users of wireless microphones in days to come.
One individual with a vested interest in the debate is Shure's Edgar Reihl, a technology director in advanced development at the Niles, IL-based company. Reihl, who has been following the controversy closely for almost four years, making frequent trips to Washington D.C. to lobby on behalf of wireless microphone users and manufacturers in front of both members of Congress and the FCC, is currently in the process of developing a set of proposed testing procedures that will be submitted to the FCC Office of Engineering and Technology.
"At this point in time, the FCC hasn't set forth any specific goals, standards, or even expectations for the next round of testing," he explained in the closing days of October. "Like other interested parties, Shure has been invited to help in the process of formulating workable testing procedures. We've also been asked to assist in obtaining the equipment needed for the tests. It's our expectation that some of us from Shure will be allowed to go observe and participate in the testing itself to whatever extent the FCC will allow, and prior to that, we will submit our own test plan, which I'm working on right now."
Reihl relates that his test procedures will call for both laboratory and real world field studies in which wireless microphones will be tested both on their own and alongside the new White Spaces prototypes in combination with DTV signals. The tests will focus specifically on the ability of the proposed new devices to detect signals coming from a wireless mic, as well as what actions to avoid interference the spectrum-sensing devices will take when they meet up with a wireless signal."
This kind of testing places a lot of stress on the new White Spaces devices, in that it's requiring them to handle a pretty wide, dynamic range," he says. "On the one hand, you're asking them to detect and adjust for DTV signals, which are very strong, and on the other, we're asking that the same be done for wireless microphone signals, which are rather weak by comparison. In an ideal testing scenario, more than one wireless microphone signal will be present, as will more than one DTV signal. The prototypes have to be capable of accurately detecting how many wireless mics are operating in the bandwidths, and these tests need to be performed across a wide range of different situations."
Given high priority within Reihl's proposal to the FCC is a battery of outdoor tests conducted at a sporting event that will most likely be a football game. Challenging on a number of levels because of the imposing size of environment involved, these tests will also be exposed to a multitude of additional TV and other signals not present within the indoor confines of the laboratory.
As for what the next generation of new prototype White Spaces devices will look like, Reihl can only speculate. "This time, they are going to be careful to make sure things are operational, properly configured and fully functional," he believes. "I don't believe we are going to see the kind of high-level, intelligent devices that we'd like to see just yet. The first step is to get these new offerings to detect wireless microphone signals properly. Once that's accomplished, then the next step is to determine how they are going to respond in kind."
The public notice issued last month by the FCC calling for more White Spaces study makes no mention of when the new testing may occur, how long it will take or when a ruling can be expected on the issue, nor does it technically reveal what exactly will be tested, calling instead for interested parties to contact the Commission if they have a device they want evaluated.