| 摘要 |
In an electronic apparatus including a reference oscillator and an interferi ng part that generates an interference signal having a spectral component withi n a receiver bandwidth, the reference oscillator supplying a reference oscillating signal to the interfering part from which reference oscillating signal the interference signal is derived, amplitude of the interference signal within the receiver bandwidth is reduced by angle modulating the reference oscillating signal with a sinusoidal signal to generate an angle modulated interference signal having a reduced carrier amplitude and modulation sidebands that are outside of the receiver bandwidth. The angle modulated interference signal preferably has a modulation index, (.beta.), that is close to a solution of the equation J0(.beta.) = O, where J0 is a Bassel function of the first kind. Angle modulation may alternatively be accomplished by applying direct frequency modulation to the reference oscillator with the sinusoidal signal to generate a modulated reference sign al and then applying the modulated reference signal to the interfering part, or by phase modulating the reference oscillating signal with the sinusoidal signal prior to supplying it to the interfering part. Where the interference signal has an interfering spectral component within a measurement bandwidth, the amplitude of the interfering spectral component is reduced by using a deterministic, non-noise modulating signal, such as a sawtooth waveform modulating signal, to angle modulate a clock signal from which the interference signal is derived.
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