| 摘要 |
Disclosed is a table lookup based phase calculator for a high-speed communication using normalization of input operands which can reduce the size of a phase table by converting respective input data into a sign and a magnitude, respectively, normalizing the magnitude of converted signals within a predetermined range, and reading the phase table using only upper L bits of the normalized input data. The phase calculator includes two absolute value operation units for calculating a magnitude of input data represented in a 2's complement, a normalization factor operation unit for calculating an amount of shift left by calculating leading zeros, a variable shifting unit for performing a shift left operation as much as a normalization factor determined by the normalization factor operation unit, an address generating unit for generating a lookup address of a phase table using only upper L bits of the two normalized input data, an arctan storage unit for storing pre-calculated arctan values according to the lookup address of the phase table, and a phase expanding unit for converting a phase value between 0 and pi/2 into a phase value between -pi and pi.
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