公开(公告)号：US10707894B2

公开(公告)日：2020-07-07

申请号：US15900598

申请日：2018-02-20

Applicant: Renesas Electronics Corporation

Inventor： Takashi Oshima ,  Tetsuo Matsui ,  Mitsuya Fukazawa ,  Tomohiko Yano

IPC: H03M3/00 ,  H03H21/00 ,  G01S13/02 ,  G01S7/35

Abstract: A modulator includes an analog integrator including an analog circuit and a quantizer quantizing its output signal. An external input signal is input thereto. A modulator is coupled to the latter stage of the modulator, and includes a quantizer. A probe signal generation circuit injects a probe signal to the modulator. An adaptive filter searches for a transfer function of the modulator by observing an output signal of the quantizer in accordance with a probe signal. Another adaptive filter searches for a transfer function of the modulator by observing an output signal of the quantizer in accordance with the probe signal. A noise cancel circuit cancels a quantization error generated by the quantizer using search results of the adaptive filters.