High Frequency Phase Reference Standard Signal

摘要

A pre-characterised high frequency signal (14) is provided by means of a non-linear circuit, for example an amplifier circuit (10), fed with a first signal (12) with a component at a first, fundamental, frequency (FO). The amplifier circuit generates an output signal comprising harmonic components (14h1, 14h2, 14h3) having stable and predetermined phase relation relative to each other. Information concerning the phase relation of the harmonic frequency components is provided, for example by means of a data file (16). At least two of the harmonic components are at the tenth or lower harmonic frequencies. The signal strength of such low-order harmonic components may be relative high, thus enabling the provision of a pre-characterised high frequency multi-tone signal from the amplifier circuit with high signal to noise ratio.

主权项

1. A method of providing a pre-characterised high frequency signal, the method comprising the steps of:
providing a non-linear circuit, feeding a first signal having a first, fundamental, frequency into the non-linear circuit, the non-linear circuit generating an output signal comprising components at a plurality of harmonic frequencies, the components of the plurality of harmonic frequencies having stable phase relation relative to each other, and providing information concerning the phase relation of said plurality of harmonic frequency components, such that the output signal is in the form of a pre-characterised high frequency multi-tone signal, wherein at least two of said plurality of harmonic frequency components are at the tenth or lower harmonic frequencies, and the output signal from the non-linear circuit does not contain any high frequency components which are not harmonics of the or each fundamental frequency fed into the non-linear circuit, whereby the pre-characterised high frequency signal can then be used, within a high-frequency measurement system for measuring the behaviour of nonlinear high frequency devices, as a phase reference standard with which absolute phase and magnitude measurements can be obtained.