Design of a 32 element rotman lens at 220 GHz with 20 GHz bandwidth

Applications in radar systems and communications systems require very often antennas with beam steering or multi beam capabilities. For the millimeter frequency range Rotman lenses can be useful as multiple beam forming networks for linear antennas providing the advantage of broadband performance. The design and development of Rotman lens at 220 GHz feeding an antenna array for beam steering applications is presented. The construction is completely realized in waveguide technology. Experimental results are compared with theoretical considerations and electromagnetic simulations

T-SENSE a millimeter wave scanner for letters

Letter bombs are an increasing problem for public authorities, companies and public persons. Nowadays every big company uses in his headquarters inspection system to check the incoming correspondence. Generally x-ray systems are used to inspect complete baskets or bags of letters. This concept which works very fine in big company with a large postal center is not usable for small companies or private persons. For an office environment with a small number of letters x-ray systems are too expensive and oversized. X-ray systems visualize the wires and electric circuits inside the envelope. If a letter contains no metallic components but hazard materials or drugs, the dangerous content is invisible for the most low-cost x-ray systems. Millimeter wave imagining systems offer the potential to close this gap

Radar technology in hot rolling mills

Technological advantages and decreasing costs are the reasons for the success of radar measurement systems for hot rolling mills. Contrary to light waves, radar radiation at the selected frequency range is insensitive to steam and dust. With high accuracies and robustness, the radar system works under harsh environmental conditions. Thereby, little maintenance and comparatively low investment costs are required. In the following, a first measurement system based on radar technology for width measurement in hot rolling mills will be presented

Synthesis and design of narrowband bandpass filters in waveguide technique

The design and realisation of a high order bandpass filter for millimetre wave signals is presented. It is purely based on split-block hollow-metal waveguide technology. The synthesis process starting at the equivalent lowpass filter is demonstrated, involving the use of K-inverters and equivalent circuits for waveguide discontinuous. This results in a compact iris filter with less than 1.2GHz bandwidth at 94GHz and more than 40 dB suppression at 0.5 GHz offset while the insertion loss is kept as low as 3 dB. The design is verified by EM simulation and experimental characterisation of a manufactured prototype to underline the potential of the filter for innovative system design in the millimetre wave range

System design of a fast W-band line scan camera using a broadband SFCW approach

In this paper the development of a W-band line scan camera for the use in industrial quality control applications is described. In order to achieve a high line scan rate, a DDS-based baseband generation approach is employed to drive multiple pixel clusters. Each cluster comprising four channels is operated in a time-division multiplexed mode. This allows for the channel clusters to be cascaded and enables wide scan lines without causing additional timing or configuration overhead. The novel system approach is based on independent frontend modules enabling transmission and reflection measurements as well as hybrid geometries. Using flexible dielectric waveguides and 3D printed support structures, arbitrary pixel configurations can be realized in space-constrained environments. The scan time of below 2 ms for a scan line of arbitrary width qualifies the system for the use in real time measurements on conveyor belts with speeds exceeding 5 m/s

Polarimetric millimetre wave SAR for precision farming applications

A high resolution imaging millimetre wave SAR delivers three key parameters important for precision farming applications, namely range, reflectivity and polarization state. The reflectivity gives information upon the type of crop and its humidity. Especially in the millimeter wave region young growing green plants exhibit a considerably higher reflectivity than older, dry leaves. Dependent on the transmit-receive polarization also indications are given upon the humidity of the underlying soil. Polarimetry also allows to judge the ripeness of the grain as the geometry of the ear is changing during the ripening process

Radarsensoren zur präzisen Breitenbestimmung unter widrigsten Bedingungen

Under the rough environmental conditions of hot rolling mills, conventional measurement systems can often not be used. IMS Messsysteme GmbH has therefore developed a width measurement system based on radar technology which allows for stable and robust width measurement under harshest environmental conditions. Further advantages are the high robustness, compact setup and very low maintenance effort. Additionally, no safety precautions are required for operating the system