| 摘要 |
PROBLEM TO BE SOLVED: To improve SNR by not multiplying local signal by a signal generated by DDS. SOLUTION: A digital receiver 1 extracts a target signal as digital data from an analog signal frequency-converted by a heterodyne system, and the digital receiver includes a coder 120, alternately making the positive/negative sign of digital data output from an ADC 101 invert; a decimation filter 121 for extracting a component having a low-frequency, from the digital data output from the coder 120 and decimating the data from the digital data of the extracted component having the low-frequency; and a multiplier 122 for multiplying an output from the decimation filter 121 by an output from an NCO 107. COPYRIGHT: (C)2010,JPO&INPIT |
