When you step inside the anechoic chamber at UMKC, the first thing you’ll notice is the silence. Try yelling, and the sound goes nowhere. There's nothing for it to bounce off.

That’s exactly the point. 

An anechoic chamber is a quiet, foam-lined room for electromagnetic waves. Electromagnetic waves power radar systems, wireless communication and the devices we use every day. These waves will reflect off almost anything: walls, tables, people walking nearby. In an ordinary lab, these reflections can create interference that corrupt measurements and produce unreliable results. However, this interference disappears inside the anechoic chamber since the specialized foam covering the walls absorbs the waves rather than letting them bounce around, much like how echoes are reduced in a soundproof room. This creates a clean, interference-free environment, which is essential for producing accurate and reliable measurements.

At UMKC, the anechoic chamber supports a wide range of research involving electromagnetic signals and wireless systems. Researchers can use the chamber to precisely measure and characterize antennas, as well as test and validate technologies such as signal processing methods and beamforming. Without this environment, it would be much harder to isolate signals and understand how systems truly perform.

UMKC’s anechoic chamber is the only one in the Kansas City area and open to the public, making this highly specialized research space accessible to the community. 

Matt Lindboe (M.S. ’26) was one of the very first students to work with the anechoic chamber before he graduated in May. 

"I like to say that an anechoic chamber allows us to pretend that the only things in the universe are us and whatever we're testing," Lindboe said. "The pyramidal foam absorbs any outgoing waves, so they don't get reflected back toward us." 

Under the DARPA Emon “Gaining Radar Advances with Spatio-Temporally-Variant Waveform Predictive Planning (GRASP)” project, UMKC, in collaboration with the University of Kansas' Radar Systems Laboratory and the Colorado School of Mines' ARC Research Group, are working toward improvements in radar range, signal strength and image resolution. Lindboe is part of this project, specifically conducting research on antenna design and characterization.

“Radar works by sending out electromagnetic waves and measuring how they bounce back from objects,” Lindboe said. “The challenge is that those return signals can be extraordinarily faint, especially when a target is small or far away. In an ordinary lab, detecting a weak signal is nearly impossible due to interference from external sources. However, these vulnerabilities are minimized and pretty much non-existent in an anechoic chamber.”

In particular, the team is measuring how low-power electromagnetic waves interact with small objects, similar to how water or sound waves behave. As distance increases, the objects intercept less of the wave, which makes the radar response weaker.

In one experiment inside the chamber, they used an array of eight transmitting antennas to send electromagnetic waves toward a small metallic plate balanced on a rotating post. A receiving antenna captured the reflected signal as the plate was rotated through different angles. When the plate sat at certain orientations, the receiver picked up almost nothing. But by manipulating the transmitted wave in specific ways, the team was able to help the receiver see the plate far more clearly at those difficult angles, more than doubling the strength of the received signal.

"We've seen from measurements in the chamber that manipulating the electromagnetic wave in specific ways can more than double the strength of the received signal," Lindboe said. 

The team subsequently hopes to address the broader question of how to best use multiple radar sensors simultaneously. More sensors will mean more information about a target will be provided. The team will need to figure out which sensors to use, where to place them and how to interpret the combined data. These are exactly the kinds of questions the chamber is built to answer.

This was especially important for Sai Sampreeth Indharapu’s (Ph.D. ’26) research, which focuses on beamforming. 

Beamforming is the technology behind how wireless systems direct energy toward a specific user rather than broadcasting it in every direction. Think of it like a spotlight. By controlling the phase and amplitude of signals sent through each element of an antenna array, the system can direct wireless energy precisely where it needs to go. It's used in everything from cellular networks to satellite communications and defense systems. 

Indharapu developed an AI-assisted method that predicts the correct antenna settings needed to point the beam at a given target angle. 

"A lot of existing research in beamforming focuses mainly on simulation results," Indharapu said. "There are fewer studies that experimentally validate these methods using real hardware." 

To bridge this research gap, Indharapu built a low-cost modular hardware testbed using software-defined radios (radio devices that can be controlled through software) and used the anechoic chamber to put his AI method to the test.  

In the experiment, he gave the system a target angle, such as 30 degrees. The AI then predicted the antenna weights needed to steer the beam in that direction. Indharapu rotated the transmitting phased antenna array in small angular steps, measuring the received signal strength at each angle. If the experiment worked, the measurement plot showed a peak of energy at the target angle.

"It was very rewarding when the measured beam directions matched the expected directions," Indharapu said. "It showed that the AI-assisted beamforming method and the hardware testbed were working together in a real experimental environment, not just in simulation." 

This validation was especially important for Indharapu as it was an important part of his Ph.D. dissertation that he recently defended. 

And to think it all started with a room full of foam.