| 摘要 |
PURPOSE: A number controlling oscillator, a digital frequency converter having the same, and a wireless transmitter are provided to reduce power consumption and cost of a number controlling oscillator by realizing a low spurious oscillator with amplitude data of low capacity. CONSTITUTION: A number controlling oscillator includes a phase accumulator(1) accumulating inputted phase difference data for generating phase data, and a ROM(Read Only Memory)(2) realizing a phase amplitude transformation table outputting amplitude data corresponding to the phase data. The phase accumulator(1) includes a phase register(1a) storing the phase data, and a phase operator(1b) operating the inputted phase difference data with the phase data output from the phase register(1a) by using an expression M=Fs/FD x K/L, wherein Fs indicates a sampling frequency of a signal to be output, FD indicates an upper limit value of a frequency set gap of the requested output signal, and K and L indicate random integers. The phase operator(1b) adds or subtracts the phase difference data and the phase data by a modulo operation having integers among the M as a coefficient. The phase amplitude transformation table outputs signals set up at a frequency set gap of a step calculated by another expression dF=FD/Kx L.
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