Radar applications

Overview of Radar applications

From the choice of materials through the layer stack-up to high-frequency optimised design – a high-frequency PCB confronts developers with new challenges 

In such cases, the PCB takes on the role of more than just a circuit board. Instead, it develops into a system in which aerials are implemented as planar versions. Therefore, not only the materials used but also the production processes have to meet new challenges. 

Your advantages

  • Radar does not have to be just for automotive applications
  • Limited etching tolerances or high geometrical accuracy Comes as standard at KSG.
  • Wide choice of special HF base materials available

Radar does not have to be just for automotive applications

Limited etching tolerances or high geometrical accuracy Comes as standard at KSG.

Wide choice of special high-frequency base materials available

Photo of an adaptive cruise control display in a car

For such applications, PTFE-based base materials with a permittivity of around 3.00 and a loss factor of < 0.002 are generally used. Those materials may also contain inorganic fillers and/or woven glass. The grade and type of the fillers varies according to the type of product and manufacturer.

Radar performance can be further optimised by means of copper foils with reduced treatment. Alternatively, there are epoxy-resin or PPE-based base materials which achieve equivalent characteristics

The route to fully autonomous driving is determined by radar sensor systems. Adaptive cruise control systems for medium to short ranges are used for this purpose. To achieve cost and design benefits, those base materials can be combined with conventional FR4 systems to form hybrids, while external high-frequency laminates are made use of for reliable radar function. The remaining part of the multi-layer board offers virtually unlimited design scope. The design rules for multi-layer circuit boards apply. 
Despite the specific material properties of PTFE, standard technologies such as laser drilling, mechanical processing and the application of a solder resist mask can be implemented.

Structure Laminate technology, hybrid, 8 copper layers
Material Rogers RO3003™/FR4
PCB thickness 1,1 mm
Circuit board technology High frequency, through connection, laser-drills blind holes on one side, mechanically drilled blind holes on one side, line/space: 100µm/100µm
Surface OSP
Special features hybrid structure, reduced etching tolerance ± 15µm

Frequency range restricted? Are the HF performance demands lower in comparison with the 77GHz applications? In both the above cases, high-frequency-optimised FR4 materials are mostly used. That results not only in substantial cost benefits in PCB production but also greater scope in layer stack-up design. Typically, such laminates on the top or underside or the multi-layer board are combined with FR4 materials in a hybrid system. 

High-volume representative products include lane-change assistance and blind-spot warning systems. Since processing is based on conventional FR4 materials, a broad spectrum of standard technologies can be applied – including HDI/SBU technologies. 

Structure  Laminate technology, hybrid, 4 copper layers
Material Rogers RO4835™/FR4
PCB thickness 0,7 mm
Circuit board technology High frequency, through connection, blind holes on one side, line/space: 100µm/120µm
Surface Chemical nickel/gold
Special features Hybrid structure, reduced etching tolerance ± 25µm

In the industrial environment, the diversity of applications for radar systems in the ≤ 24GHz frequency range has seen significant growth. Such high-frequency circuit boards can be found, for instance, in electronic circuitry for automatic door systems, fill-level sensors, traffic monitoring systems, anti-collision systems in robotics, and alarm systems. 

Layout of a PCB for industrial radar systems

Here is an overview of the base materials KSG can offer for your HF projects: 

ksg_tabelle_basismaterialien_hochfrequenz_en.pdf

Industrial electronics (24GHz) Fill-level sensor

The benefits KSG offers you: 

  • Contactless (more hygienic)
  • Penetration of various materials (better placement)
  • Dirt-resistant (maintenance benefit)
  • Tolerance range 1 mm to a few cm

Industrial electronics (24GHz): Door opener

The benefits KSG offers you:

  • Radar module reliably detects movements
  • Also enables detection of the direction of movement
  • Prevents incorrect opening of doors

Security systems (24GHz):
Alarm system and site surveillance 

The benefits KSG offers you:

  • Detection of moving objects including their speed, distance and angle/direction 
  • Detection up to a distance of 150m

The complexity and quantity of technical parameters for high-frequency circuit boards is enormous. Which is why it is best to consult us at an early stage of development and benefit from our decades of experience and technical expertise in the field of HF PCB technology. We can resolve your task requirements in the course of an on-site or online consultation. And it makes no difference whether you're developing a new PCB or optimising an existing product or costs.

Simply make an appointment by e-mail right now:
matthias.schmied@ksg-pcb.com

Contact partner

If you have any questions about the topic, we are happy to be your contact person.

Portrait of Matthias Schmied

Matthias Schmied
Project Engineer
Mobile+49 3721 266-391
matthias.schmied@ksg-pcb.com