New matchbox-sized radar could make its way into drones and security systems

The smaller and lighter electronics get, the more ways they can be used. A team of researchers has come up with a compact radar system the size of a matchbox that could be deployed in drones, guidance systems for people with vision problems, and other gadgets where portability and low cost are important.

Weighing in at under 150 grams (5.3 oz), the as-yet-unnamed radar prototype is powered by a 5 V battery and can detect and track a walking person at 12 meters (39 ft) or up to 20 meters (more than 65 ft) if "the target's cross section is higher." It does the job of a standard radar system – detecting the size, distance and speed of nearby objects – in a fraction of the size.

"Current radar modules are large and bulky," says Seifallah Jardak from KAUST. "They also lose out on key details because they operate using long radio wavelengths. We wanted to develop a low-power, portable radar."

Working with colleagues from the VTT Technical Research Center of Finland, Jardak and the rest of the KAUST team were able to refine the technology to run eight scans per second, up from a single scan every two seconds when the prototype was first built.

In terms of monitoring real time situations, that scan frequency is crucial. The device uses a frequency-modulated continuous wave (FMCW) type of radar, producing continuous pulses of radio waves of varying frequency that can detect small scale changes.

During testing, the radar was even able to detect breathing from someone sat in a chair. The shorter radio wavelengths used here mean a shorter range overall, but more accurate results across a smaller area.

"To limit the size of our system, we chose an operating frequency of 24 Gigahertz," says Jardak. "This enabled us to reduce the size of the microstrip antenna. Our design also has one transmitting and two receiving antennae, meaning it can better estimate the angular location of a target."

As you would expect, some compromises are made along the way – this radar isn't powerful enough for large-scale military use for instance – but for smaller, portable gadgets that need to detect their surroundings, it has plenty of potential applications.

That might mean helping those with vision problems to find their way around, or helping delivery drones to avoid obstacles as they race toward their targets. It could also be used in health care, for monitoring vital signs, or even as part of a home security setup.

Any situation where unmanned robots are used could also benefit from the tech, the researchers say. A paper describing the radar prototype is available online and you can see a video explaining the technology below.

Source: KAUST