Elianne Egli, Innovation and Processes, Science and Technology

The walls of the anechoic chamber at armasuisse S+T in Thun absorb electromagnetic waves almost completely. This unique characteristic allows the emission of electromagnetic waves or their dispersion around objects to be measured under ideal and thus controllable conditions. Atmospheric influences and backscattering from extraneous objects can be largely excluded. The results achieved are therefore reproducible and comparable. This is important if the electromagnetic emission from communications and reconnaissance systems is to be characterised and compared, but also when determining the backscattering behaviour of possible target objects.

The following measurements are typically performed in the anechoic chamber:

• Radar backscattering cross section measurements (RCS measurements) (small models, drones, reference objects, military vehicles)
• Measurement of directional radio patterns of antennas
• Characterisation of radar camouflage materials (nets and coating)
• Synthetic aperture radar measurements

A measuring site is available in Witzwil for objects which are too large for the anechoic chamber, or with frequencies which are not suitable for the existing anechoic chamber. The antenna measuring site contains a rotary plate on which large objects can be placed, a measurement tower and a measuring hut. The antenna measuring site is suitable for antenna measurements in the VHF/UHF frequency range. This system is suitable for determining antenna diagrams as well as for characterising bearing features.

This unique laboratory in Switzerland is used in particular for sovereign issues of electronic warfare.

In electronic warfare (EW) the aim is to record and evaluate the adversary’s electromagnetic emissions. The goals of electronic warfare include restricting the adversary’s intentions by disruption, deception and camouflage. Where in the optical area, for example, camouflage dress or dummy tanks are used, in electronic warfare you also attempt, for example, to lure the adversary onto a false track and to discover false tracks that have been laid by the adversary.

The laboratory's extensive and technical range of instruments allows systems to be tested and examined for relevant electronic warfare criteria. 

In addition, a mobile measuring container is available in which the available measuring equipment can be used to test large and firmly installed systems on site in the field.

An optronics laboratory equipped with modern resources is available to armasuisse S+T in Thun for the specific characterisation of optronic devices (such as binoculars, residual light amplifiers, etc.) and current camouflage materials. Here, light and laser sources as well as various detectors in the relevant electromagnetic (EM) spectrum can be examined experimentally. The spectroscopic characteristics of materials can also be checked.

The following measurements are made, for example, in the Optronics Laboratory in Thun:

• Checking the performance capacity and the performance limits of modern night vision equipment and infra-red (IR) reconnaissance systems
• Security clarifications in the area of laser and high-performance light sources (such as in the area of protective eyewear in front of laser pointers).
• Spectroscopic examinations in the area of camouflage materials (nets, camouflage dress, mobile camouflage kits)

In order to protect devices and systems against large electromagnetic field pulses and electrical (dis)charges such as a lightning strike, various large electrical charges with HPE threats can be artificially generated and simulated in the High Power Electromagnetic (HPE) Laboratory in Spiez.

The HPE Laboratory has modern equipment for nuclear electromagnetic pulses (NEMP) simulations. In addition to these simulators, further simulation equipment and generators also exist with suitable measuring equipment for simulating and measuring lightning, NEMP and HPE environments.

The following tests and measurements, for example, are performed in the HPE Laboratory in Spiez:

• Security-relevant interference immunity tests and examinations both in the military as well as in the civilian fields of application of strong electromagnetic fields
• Checking appropriate protective measures and measuring shielding efficiency
• Assessing electromagnetic compatibility (EMC) measures in the form of site surveys

In the unique explosives laboratory of armasuisse S+T, explosives (explosive agents, propellants, pyrotechnics) are analysed, ageing and stability provisions performed as well as security and environmental aspects assessed.

The secure decommissioning (breakdown) of ammunition and explosives takes place in the laboratory. The focus of work is on checking components as well as simulating technical weapon-related and ammunition processes.