Terahertz Eavesdropping (IMAGE) Brown University Caption Terahertz radiation may one day be used in wireless data networks that are many times faster than today's microwave networks. The conventional wisdom in the research community has been that, in addition to greater speed, terahertz data links would also have an inherent immunity to eavesdropping. Unlike microwaves, which travel in wide-angle broadcasts, terahertz waves travel directly from transmitter to receiver in narrow beams. The assumption was that it would be impossible to for an eavesdropper to intercept a terahertz signal without blocking some or all of the beam, which would be easily detected by an intended receiver. But new research finds that a clever eavesdropper can indeed steal terahertz signals undetected. In order for a link to be reliable, the beam's diameter must be slightly larger than the aperture of the receiver. That leaves a sliver of signal available for an attacker to steal without casting a shadow in a receiver. Credit Mittleman lab / Brown University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.