Using Radar to Improve Security and Counter Drone Threats

Security is taken very seriously at most power plants. Fences and other barriers are usually installed before construction of a plant even begins to keep curious busy-bodies, thieves, protestors, and—at the far end of the spectrum—saboteurs and terrorists out of sensitive locations. Some plants have dedicated security staff patrolling areas both inside and outside of the fence, inspecting deliveries, and maintaining around-the-clock surveillance.

And the measures are all in place for good reason. Some studies have suggested that a coordinated attack against the U.S. power grid, including strikes against some power stations, could cause widespread chaos. Billions of dollars could be drained from the nation’s economy, and some experts have suggested that thousands of lives could be lost. With the grim picture painted by some alarmists, it’s not surprising that security tactics have received more attention.

Assessing the Options

Technological advances are nothing new in the power industry. Computers have taken over control rooms, and tools such as remote monitoring, sophisticated diagnostics, and virtual training systems have all reached mainstream status. These days, security systems are also filled with new high-tech gadgetry.

There are several alternatives available to monitor plant areas for trespassers. Closed-circuit television (CCTV) systems have been around for a long time, but the systems have changed a lot since the days of VHS tapes. While video surveillance is really a necessity, it alone does not usually offer enough advanced warning to stop malicious activity. Often, the video can be used for nothing more than piecing together events after the fact. Another drawback is that weather and lighting can reduce the effectiveness of CCTV, and in some cases, it renders the systems completely useless.

Thermal cameras, microwave systems, and fiber optic solutions offer other options. Although each can be effective in certain situations, they too have drawbacks. Thermal cameras are affected by weather. Microwave technology cannot automatically cue cameras to track movement. The range of fiber optic systems is very limited. Additionally, all of these options can require lengthy installation periods, including trenching, in most cases.

Compact surveillance radar (CSR) is one of the latest methods being used to detect intruders and other threats around power plants and substations. CSR is relatively small and can be mounted practically anywhere. Best of all, it offers a wide area of coverage and can track people, vehicles, and even drones, regardless of the time of day or weather conditions.

Detecting and Stopping Drones

There are several companies that offer radar-based security systems, including FLIR Systems, Navtech Radar, Silent Sentinel, and SpotterRF. SpotterRF—a Utah-based CSR system provider—announced on August 31 the availability of a new model specifically designed for drone detection and defeat applications. The new radar system, known as the A2000, is able to detect small quadcopter drones at a range of 1,000 meters, providing early detection, tracking, and interdiction against threats to critical infrastructure, such as power plants and substations.

SpotterRF’s technology is internet protocol–based and uses standard ethernet cables with a built-in web user interface. As opposed to most 2-D ground surveillance radar applications, the A2000 provides a 15-degree vertical and 45-degree horizontal view. That ability is said to provide a true 3-D field of view, creating “an invisible perimeter well beyond other technologies.”

Drone defeat device capability is currently available for the A2000, although it isn’t allowed everywhere in the U.S., due to various regulatory restrictions. One interdiction option utilizes high-power white-light illuminators tied to a pan-tilt-zoom (PTZ) mount that slaves to the radar detection and blinds the drone’s ability to gather photos or video of a location. Another defeat method utilizes directional jammers attached to a PTZ mount that is slaved to the drone detection from the A2000. The system jams communication between the drone and the controller, or GPS if flying autonomously, causing the drone to either return to its launch point or immediately land.

Proven Technology

SpotterRF claims to have numerous power generation and power transmission customers. One example it shared with POWER was a system installed by the Bureau of Reclamation. It uses radar technology to protect reservoirs, spillways, and downstream dam approaches (Figure 1).

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1. Dam protection. In this waterfront example, one radar device (C550) monitors activity on the shore and lake surface with its field of view (FOV) denoted by the large red oval, while the C40 radar tracks movement on and around the water outlet. When one of the devices detects a threat in an alert zone, it cues a pan-tilt-zoom (PTZ) camera to track the threat, providing security personnel with a view of the target. Courtesy: SpotterRF

The Bureau is said to have chosen the SpotterRF solution because it mounts quickly on guardrails, stair rails, concrete walls, or other existing structures, while other technologies required concrete pads, metal support structures, trenching, power access, and additional communications costs. SpotterRF’s radar units weigh as little as 1.5 pounds, use only about 8 W of electricity, can be solar powered, and are easily relocated, if required. System prices are comparable to other surveillance options but offer much greater coverage and functionality.

“Our C950 will track a person walking up to 1,350 meters away and has a coverage area of nearly 300 acres for one radar system that weighs about 5 pounds,” SpotterRF CEO Logan Harris told POWER. “So we have the ability to cover very large areas.”

In another example, 60 standard CCTV cameras would have been needed to cover the same area monitored by three SpotterRF CSR units and one PTZ camera (Figure 2). When a CSR unit detects a threat, it can be programmed to automatically attach a GPS tracker to the target and cue a dual optical and thermal camera to follow its movement.

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2. Eye in the sky. The compact surveillance radar system and pan-tilt-zoom camera shown in this image are installed at a coal-fired power plant in Wyoming. Courtesy: SpotterRF

Deterring Malicious Activity

One difficulty faced by all security surveillance systems is distinguishing between threats and nonthreats. In most power plant locations, there are wild animals that roam the area and highways or roads nearby with standard traffic patterns, so setting up a system to warn based on motion alone can result in a lot of false alarms. That is where SpotterRF’s experience and high-tech tools come into play.

First, the CSR system is programmed with site-specific “geozones.” This allows motion detected in some zones to trigger alarms, while movement in other areas just gets monitored. Then additional layers of filtering are applied, such as behavioral filters.

“We bring the radar system data into our network input/output integration server, which allows programmers to define zones and apply rules,” Harris explained. “We install the system with basic filters and then come back in a few days to review the alarms. If we see a group of deer, for example, come through an area every night between 9 p.m. and 11 p.m., and they generally move in a certain way, we define a behavioral filter so the system doesn’t alarm when it observes that behavior.”

In addition to behavioral filters, SpotterRF uses an artificial intelligence engine, or neural network, to learn normal activities around a site. The system can recognize and classify targets as people, animals, or vehicles, and then alarm only when it observes suspicious behavior.

“We’ve had good success in reducing nuisance alarms in that way,” said Harris.

Harris said that many would-be wrongdoers plan their attacks and scope out areas before committing actual crimes. This is another area where CSR has been very successful in preventing malicious activity.

In remote areas where it can be difficult for security personnel to respond quickly to threats, the system can be programmed to activate spotlights that can illuminate the target and move with it using GPS. Loudspeakers can also be used to warn intruders to stay away and inform them that activity is being monitored. Often, just the threat of being caught is enough to scare off perpetrators. For owners, having the knowledge that someone is scoping out your property gives you time to increase security and focus on catching the bad guys.

“By having advanced warning, a lot of things can be done to prevent an incident from ever happening,” Harris said.

Aaron Larson is a POWER associate editor.