Researchers at a U.S. university have developed a technique to create plasma antennas that look like a \u2018lightsaber\u2019 and could send and receive radio signals in space or aircraft without the need for complex mechanical installation.<\/p>\n
\u200bAccording to the scientists, these laser-generated plasma-filament antennas have never been shown to work before, claiming it as a world-first demonstration of the technique.<\/p>\n
\u200b\u201dThis is the first step, but it is a big step \u2013 it is the first time anyone has ever demonstrated that plasma-filament antennas can work,\u201d said Prya Darshni, corresponding author of the study and a Ph.D. student at North Carolina State University.<\/p>\n
\u200bTraditional metal antennas used for radio wave communication are prone to installation setbacks, particularly in space. They can either bend or break when unfolding in space, she highlighted.<\/p>\n
Drawbacks of physical antennas <\/p>\n
\u200bMoreover, due to the big and bulky nature of physical antennas, they need a lot more room and inflate mission costs, while requiring expertise for effective use.<\/p>\n
\u200bOne can argue to cut the budget and payload weights for antennas; one may simply reduce their length. But it is easier said than done. Researchers noted that antenna length is a key factor in determining which signals radio antennas can transmit or receive.<\/p>\n
\u200b\u201dThe length of an antenna [\u2026] controls the frequencies at which radio waves can be transmitted and received,\u201d said Darshini. \u201cBut manipulating the length of antennas to sweep a desired range of frequencies can be challenging in some applications \u2014 such as space exploration technologies,\u201d she added.<\/p>\n
\u200bTo overcome these bottlenecks, the team turned to lasers<\/a> to generate plasma beam antennas that can be tuned to any length or angle without requiring extra space or tricky, tedious adjustment to get a glitch-free signal.<\/p>\n \u200bBuilding plasma antenna<\/p>\n During their experiments, the researchers fired a laser beam of a specific power and diameter that ionized a thin strip of air, forming a glowing beam or \u201cfilament\u201d of plasma<\/a> that looked like a \u201clightsaber.\u201d<\/p>\n \u200bBut to give these laser-induced beams the mysterious powers, an extra nudge was needed to establish a radio<\/a> <\/a>connection. This was needed to make the plasma antenna work.<\/p>\n \u200bTo make that possible, the researchers developed a contact-free way to send radio signals to it. They placed a metal ring around the laser beam, allowing the beam to pass through the center. The ring acts as a capacitor, generating an electromagnetic field that transfers radio signals to the plasma without touching it.<\/p>\n \u200bFollowing this, the electromagnetic wave can transport electrons in the air that are pushed to the edge of the plasma and show that a laser-induced plasma filament could radiate EM waves much like a typical antenna, the study reported.<\/p>\n \u200b\u201dNow that we\u2019ve shown it is possible, we can begin improving its performance,\u201d said Darshni.<\/p>\n \u200bNoting the research is still in its early stages, she confirmed the work is ongoing.<\/p>\n