Spur-reduced numerically-controlled oscillator for digital receivers

A technique involving phase dithering that reduces the complexity of numerically controlled oscillators (NCOs) is presented. Spurious magnitudes due to finite word-length effects in phase representation are accelerated from the usual -6 dBc per phase bit to -12 dBc per phase bit. This is at the expense of a small increase in system noise. This permits the use of a smaller number of phase bits and results in an exponential decrease in system complexity compared to nondithered NCOs