| 摘要 |
PROBLEM TO BE SOLVED: To reduce multi-path interference in a disaster management radio network using analog waves and in a general FM receiving device. SOLUTION: The unit performs phase hardware and software inversion. In the hardware inversion, two tuner sets are used, two receiving points are set, and opposite-phase input points are searched in a low-level noise region, while in-pahse points are searched with respect to desired waves, and synthesizes the signals received at the points to physically obtain the clearest level. In the software inversion, one receiving point is used. After DSP demodulation, low-level foreign waves are continuously received, recorded, and patterned by analysis, to be output as a generator output of the same pattern. Slightly later, the generator output is input into a logic circuit that synthesizes opposite-phase waves of the patterned waves and received waves. The two methods are used according to the desired to undesired signal (U/D) ratio. COPYRIGHT: (C)2011,JPO&INPIT
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