The November 2022 issue of IEEE Spectrum is here!

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The Atlanta Journal-Constitution had a strange little story late last week about an unknown man's photo being associated online with hundreds of arrest records in DeKalb County, Georgia.  The AJC says that "... the same man’s photograph is posted on most inmate records for anyone booked in the jail prior to 2000."

The AJC says that the man's photo is found on arrest records for both men and woman going back to at least 1983.

The error was found by the AJC when it was searching for an inmate's picture.

The DeKalb Country sheriff says his IT staff is looking into the error, and he says it wasn't deliberate. More likely it was that this man was the first person booked in jail when the sheriff's department's web site first went up, he says.

Of course, this does beg the question of why this photo is apparently on most, but not all, inmate records prior to 2000, and why it took so long - and a newspaper - to discover it.

I surmise also that no one bothered to verify the arrest reports before making them available online, since I doubt the web site existed way back in 1983.

The Conversation (0)

Metamaterials Could Solve One of 6G’s Big Problems

There’s plenty of bandwidth available if we use reconfigurable intelligent surfaces

12 min read
An illustration depicting cellphone users at street level in a city, with wireless signals reaching them via reflecting surfaces.

Ground level in a typical urban canyon, shielded by tall buildings, will be inaccessible to some 6G frequencies. Deft placement of reconfigurable intelligent surfaces [yellow] will enable the signals to pervade these areas.

Chris Philpot

For all the tumultuous revolution in wireless technology over the past several decades, there have been a couple of constants. One is the overcrowding of radio bands, and the other is the move to escape that congestion by exploiting higher and higher frequencies. And today, as engineers roll out 5G and plan for 6G wireless, they find themselves at a crossroads: After years of designing superefficient transmitters and receivers, and of compensating for the signal losses at the end points of a radio channel, they’re beginning to realize that they are approaching the practical limits of transmitter and receiver efficiency. From now on, to get high performance as we go to higher frequencies, we will need to engineer the wireless channel itself. But how can we possibly engineer and control a wireless environment, which is determined by a host of factors, many of them random and therefore unpredictable?

Perhaps the most promising solution, right now, is to use reconfigurable intelligent surfaces. These are planar structures typically ranging in size from about 100 square centimeters to about 5 square meters or more, depending on the frequency and other factors. These surfaces use advanced substances called metamaterials to reflect and refract electromagnetic waves. Thin two-dimensional metamaterials, known as metasurfaces, can be designed to sense the local electromagnetic environment and tune the wave’s key properties, such as its amplitude, phase, and polarization, as the wave is reflected or refracted by the surface. So as the waves fall on such a surface, it can alter the incident waves’ direction so as to strengthen the channel. In fact, these metasurfaces can be programmed to make these changes dynamically, reconfiguring the signal in real time in response to changes in the wireless channel. Think of reconfigurable intelligent surfaces as the next evolution of the repeater concept.

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