Design of an Integrated Wideband Amplitude-Modulated Noise Source

摘要

The report describes the results of a project directed towards designing and constructing a miniature, wideband, AM-modulated, noise generator. The modulated noise generator is a circuit that can test the operational performance of a typical AM receiver on a go no-go basis. In other words, this single circuit serves and accomplishes the same task (without electronic tuning) that a tuneable, modulated, signal generator does when making operational tests on AM receiving equipment. The report also discusses the selection of the noise source and audio oscillator used to amplitude modulate the noise source. It is seen that by choosing an audio relaxation oscillator to drive a single diode as a noise source, a circuit may be realized that may be fabricated using hybrid integrated circuit techniques. The impact of the hybrid integrated circuit techniques is that the noise generator size is substantially reduced to the point that it may be incorporated in the actual AM receiver to be tested. (Author)