| 摘要 |
PROBLEM TO BE SOLVED: To remove noise from a DSB signal, accurately.SOLUTION: A signal processor, for receiving a double sideband wave signal and removing noise superimposed only on one sideband wave on an RF bandwidth, includes demodulation means for orthogonal demodulation of the double sideband signal into a baseband signal having a positive frequency bandwidth and a negative frequency bandwidth, and noise elimination means for eliminating a noise component included in an in-phase component outputted from the demodulation means, based on a quadrature component outputted from the demodulation means. The signal processor also includes quadrature component bandwidth extraction means for extracting a noise component of one frequency bandwidth within the positive frequency bandwidth and the negative frequency bandwidth on a quadrature component outputted by the demodulation means. The noise elimination means includes phase rotation means for rotating a noise component, extracted by the quadrature component bandwidth extraction means, by -π/2 or π/2, and synthesis means for removing noise, superimposed on a signal component, based on a phase rotation noise component outputted by the phase rotation means, from a baseband signal component which is an in-phase component of output from the demodulation means.SELECTED DRAWING: Figure 1 |
