Myth Busting Common Radar Misconceptions

Myth 02: Radar can’t see multiple things at once.

This myth is somewhat true. Before diving in, let’s clarify the initial statement. Radar does not “see.” There are no optical capabilities from radar. Some radars can provide an image, in very close-range cases, as a high-resolution spectrogram that resembles “sight.” Rather, radar directs energy in the spectrum across physical space, like a light penetrating darkness. And, just like a light in darkness, the intensity of the light, how it is pointed, how it is focused, provides different levels of information. If the light beam is very bright, and pointed in a very specific direction, and focused on a very small area of space, a vision-based system would need to dwell on that area and would be most interested in the immediately adjacent areas for additional context and definition. This is why optical systems are best when focused on a specific object and are less than ideal as a primary search sensor.

Regarding “multiple things at once,” historically, only multi-million-dollar Defense radars could generate multiple beams concurrently. Commercial radars have typically used a sequence of micro-second bursts of RF energy to illuminate an area of the scene. Just as with Myth #2, most radars transmit a signal into large areas of the scene and do so repetitively. Each signal return might contain multiple targets, and the radar also needs to be able to distinguish amongst objects in the scene (again, see Myth #2). But the radar is not looking in two directions at the same time, rather it is employing a randomized search pattern across the scene.

What is important is to distinguish between searching and tracking. The radar needs to be able to search the field of view very quickly and simultaneously track different objects in the scene. Electronically scanned array (ESA) radars have a native capability to search while track (SWT), meaning the radar continuously searches the scene while also directing energy more often and more robustly at specific objects in the scene to generate high fidelity information about the object – size, velocity (micro-Doppler), orientation, precise location in azimuth, elevation, and range, time to contact, time to intercept, and more.

Only ESA radars can actively search and track at the same time, providing significantly better performance and more precise object data. Echodyne is the only provider of commercial ESA radar, known as MESA (metamaterials electronically scanned array). MESA radar collects, processes and transmits object data 10 times every second; to the security team, this appears and functions as simultaneous objects awareness.

Myth 03: Radar is too costly because so many units are required to cover an area.

What makes the myth less true moving forward, is both mission and technology. New developments in radar technology have drastically reduced the C-SWaP, while delivering the precise radar data required for unique and exacting defence, government, and security missions and solutions including drone detection, counter-UAS, event security, multi-domain perimeter intrusion detection, ISR (intelligence, reconnaissance, surveillance), forward-base protection and more. MESA (metamaterials electronically scanned array), small form-factor radar delivers unparalleled accuracy at a commercially accessible price.

Historically, however, the cost-driver for radar has been related directly to the objective and technology manufacturing requirement. Radar has long been the primary sensor for maintaining situational awareness of large areas such as coastal radars, and very large areas such as radars that detect missiles across continents. The technology category for these radars is “electronically scanned array” (ESA). Constrained to critical military and national security applications due to extremely high cost, size, weight, and power (C-SWaP) and complex operational requirements, these radars have delivered excellent value for price as these early warning systems have proven highly reliable and necessary for global safety and security.

The problem is leveraging ESA radars for smaller missions and security applications has been the gap between price for performance. Historically, the SWaP has proven as irreducible as the cost and would never fit a ROI profile outside of Defense. Nearly all infrastructure and assets have different risk profiles, too. The threat to infrastructure and assets has historically been quite distinct – no one is worrying about missiles and mortars in civilian spaces.

As drones proliferate the threat landscape for domestic infrastructure, MESA radar fills the gap by delivering true ESA capabilities – search-while-track, precision data, reliability – in an ultra-low and low- SWaP solid state form factor that is cost accessible.

Myth 04: Radar doesn’t see well in rain or fog.

100% myth. While there are properties of the spectrum where water can deteriorate the radar signal in some fashion, radar remains the only technology to be virtually immune to weather conditions. Radar also handles different lighting conditions with the same ease. 24/7 reliable operation makes radar the most dependable and versatile sensor in the solution stack.

Myth 05: Radar generates too many false positives.

This is partially true for some freestanding radar, but untrue at the system level. Radar will detect all movement in the airspace – organic and inorganic. Differentiating between a bird and a drone is not always possible, for example. Advanced radar classification, like that found in MESA radar, can clarify the threat risk leveraging long-dwell micro-Doppler capabilities. However, radar is not the sensor that confirms object identification; that is generally accomplished with “eye-on” confirmation via personal observer or camera. This is the primary reason that no security system relies on only one sensor – each sensor has a role to play in a comprehensive, multi-sensor security solution. Radar is the most cost-effective sensor for large volumes of airspace, generates the baseline data set for any objects detected in the area, classifies objects of interest to improve threat probability, and cues expensive optical sensors with positional updates to train advanced video analytics that further interrogates the object, providing a positive identification for subsequent tactics, techniques, and procedures (TTPs).

Myth 06: Radar doesn't need to be precise if there's a good camera analytic being used.

Myth! Radar provides three essential security solution elements:

• Baseline search capabilities for large areas and volumes
• Precision data in four dimensions: azimuth, elevation, range, velocity
• A high data processing rate.

These three core functions cannot be accomplished with optical sensors alone, nor with optics plus analytics. The promise of video analytics implies more capabilities tomorrow but the challenge of searching large volumes of space while also focusing on key items in the scene will always force a multi-sensor solution. Let’s compare these three radar competencies to camera and analytics capabilities.

Large Volume Search
One of the revolutions in optical sensors has been digital magnification, enabling cameras to focus on small objects at long range. When the camera resources are zoomed onto an object, though, this comes at the expense of seeing the larger scene. The same is true in reverse; scanning large volumes of space reduces the ability to detect small objects. Radar object detection is not impeded by calibrating a zoom. Rather, radar detects and captures location and movement data on all objects moving within the field of view. Radar excels at surveilling large areas and the better the technology of a particular radar, the more precise the object location data.

Precise Object Data
The object data elements are required for pointing and focusing the optical sensor on the object. With precision data for an object’s position on the horizon (azimuth), altitude (elevation), distance to the object (range), and the speed of the object (velocity), optical sensors can zoom to the object’s exact location. Once radar is tracking the object, it needs to generate a data stream sufficient for the optical sensor to smoothly pan and reliably maintain focus on the object.

Data Processing Rate
When drones are the risk, radar data must be a minimum of 4 Hz (four times per second), with higher speed data providing a smoother viewing experience. A data stream of 10 Hz (ten times per second) is optimal for locking onto the object.

Myth 07: Radar can't mitigate drones, so detection-only is unnecessary or not required if cost prohibitive.

100% myth! Radar spans the security umbrella, from baseline search to informing operation of cUAS mitigation systems with the precision coordinates required to safely and effectively interrupt the flight of an intruding drone. Cameras are unable to mitigate drones and nearly every security TTP (tactics, techniques, procedures) requires cameras for “eyes-on” confirmation of objects of interest. More importantly, mitigation is complex and risky without the exact location of the object; radar provides the specific location data required for safe, effective mitigation. Radar provides highly reliable, cost-effective drone detection searching and tracking capabilities and, when paired with optical sensors, provides the data foundation for mitigation and any police or prosecutorial action against an intruder.

Myth 08: Radar is hard to tune.

Myth! Modern radar is combined with intuitive software to provide ease of configuration for site, mission, and operator requirements. If the radar is permanently sited, the initial configuration will be measured in minutes, not hours, and will require very little management going forward.

If the radar is used in a portable fashion, frequent configurations can be stored to simplify use. True portability in radars should mean the radar can be up and running in less than twenty minutes (<20 minutes). All radars receive software updates, which should be installed frequently for optimal operations, but this is no different from other sensors and systems.

Myth 09: Radar is hard to include on mobile systems due to variables of vehicle and road characteristics.

For portable security applications, conventionally known as “mobile,” this is a myth! Solid state radar is a valuable sensor for mobile security trailers that are deployed to various locations as needed and remain fixed during hours of active threat tracking and detection. The radar is mounted to a mast alongside other sensors, using common brackets, hardware, power and data connections.

This is true with regard to on the move applications (OTM). While a challenging problem to solve, it is not impossible and there are radars calibrated to account for the variability of vehicles and road characteristics.

Mobile sensing is a complex challenge as the position of any sensor at time of transmission and time of reception must be known with great precision. The problem is not unique to a specific sensor, though positional accuracy is always important for radar.

The branch of physics that deals with motion is called kinematics, or sometimes called the geometry of motion. A mobile surveillance or mobile mitigation system must consider concepts like distance, speed, velocity, and acceleration of each of the sensors within the system and how these values change over time. Of course, time in this case is measured in milliseconds, with the system needing to know exact location at a speed of 100 to 500+ times per second. With that positional accuracy known to all elements of the system at both signal transmission (Tx) and signal reception (Rx), the system can send and receive signals with the capabilities of a fixed position.

The degree to which a radar can operate with precision while OTM is determined by multiple factors including physical design, precision of onboard GPS, data processing rate, and more.

Myth 10: Radar can’t operate as a standalone sensor.

100% myth! Radar has operated as a standalone sensor since its inception. For complex perimeter intrusion and critical infrastructure security, radar is best when deployed as part of a multi-sensor solution. However, there is nothing fundamental to radar that precludes standalone operation. In fact, ultra-low SWaP (size, weight and power) man-portable, stand-alone radar is often used for missions in austere environments including discreet ISR (intelligence, reconnaissance, surveillance).

Myth 11: Radar does not “alert”

Myth! All data can produce alerts within systems. And radar data, as a baseline, is responsible for both alerting and directing other sensors to confirm the alert. This is accomplished via integration with existing sensors and systems including C2 and VMS.

Myth 12: You can’t mount radar on high poles/structures.

Myth! Radar can be mounted wherever it is safe to do so. Structural rigidity is important, and high-performance radar with high SWaP characteristics can be challenging to mount on poles or structures. Modern radar, like Echodyne’s low and ultra-low SWaP radar, can be safely mounted on poles or structures. In fact, Echodyne radars are so light and powerful that they are often mounted four at a time on masts and used on large, tethered drone platforms as portable towers.

Myth 13: Radar interferes with other RF technology.

Could be true. When used properly and with permission of the spectrum regulator, radar operates within its own boundaries and does not interfere with other RF uses or applications. However, it is true that radar uses the radio frequency spectrum which is a shared resource for mobile, satellite, communications, and other applications. As an active emitter, radar must operate in areas of the spectrum permitted for that use in that country or jurisdiction. If used indiscriminately, radio frequency sensors can create and experience interference.