BROADBAND 60 GHz COAXIAL NOISE SOURCES

The Phase I objective is to develop a 10 MHz to 65 GHz (or minimum 2 GHz to 60 GHz) coaxial noise source with a low VSWR. The noise source will use a millimeter-wave noise diode developed in 1992 (as a result of contract DAALO1-89-C-O9I6) and utilize 1-85 mm connectors. It will consist of a broadband impedance-matching section, circuitry containing the diode and DC blocking capacitors, and a temperature compensating current regulator. By using a technique, which separates the noise source into 3 sections (impedance-matching, DC blocking, and bias), attention can be paid to these basic elements of 60 GHz coaxial components. Noise sources are special by being very broadband of nature and are required to have a low VSWR in both on and off conditions. The broadband impedance-matching shall provide a constant spectral density of noise at the output, while maintaining the low VSWR as the noise diode is switched on and off, thus matching the package loss and diode impedance in these two states. It is a challenge to simultaneously obtain effective DC blocking/AC coupling at very low and very high frequencies. Successful completion of Phase I will therefore ensure useful results for development of other 60 GHz components or 110 GHz noise sources.