In the sub-millimetre region – between the microwaves and infrared spectral regions – materials exhibit properties that can have applications that span biomedical technology to wireless communications. Despite these and potential applications in Earth observation, it has yet to be fully exploited. To date, the EU has been dependent on electronic components and devices from the USA, an imbalance affecting Europe's scientific and commercial exploitation of the sub-millimetre region. The EU-funded MIDAS (Millimetre-wave integrated diode and amplifier sources) project aimed to redress this imbalance. Millimetre waves have been the subject of intense research in recent years. They are particularly interesting to astronomers since it has been estimated that nearly half the total luminosity and almost all photons emitted since the Big Bang are in wavelengths corresponding to the gigahertz (GHz) and terahertz range. Research focused on delivering a power source operating at frequencies between 270 and 300 GHz for wave-space science and Earth observation instrumentation. This was previously unavailable in Europe. The designs of solid state frequency multipliers were proposed during the first phase of the MIDAS project. These were all designed with a European model of integrated Schottky varactor diodes. Dedicated technology was also developed to enhance the device performance – in particular, improve the power handling capabilities from 50 up to 400 milliWatt. The monolithic microwave integrated circuit technology applied to Schottky diodes is key to reproducible circuit performances. The MIDAS project developments are expected to make European Space Agency missions possible solely with European devices.
Millimetre waves, Earth observation, solid state frequency multipliers, Schottky varactor diodes, monolithic microwave integrated circuit