| 摘要 |
<p>A phase detector which does not require any large-capacity memory for an arctangent table and can accurately calculate the phase of an input digital complex baseband signal point within a practical calculating period of time independently of the amplitude value. This detector judges whether or not the phase of the input signal point coincides with a reference phase point by rotating the phase of the input signal point clockwise by a prescribed angle. When the signal point after the rotation is ahead of the reference phase point, the phase of the input signal point is further rotated by a half of the prescribed angle; when the signal point after the rotation is behind the reference phase point, the phase of the input signal point before the rotation is rotated by a half of the prescribed angle. The rotating angles 180 DEG , 90 DEG , 45 DEG , ..., of the rotation are stored in a table. When the signal point coincides with the reference phase point after repeating the rotation several times, or when no coincidence is detected although the signal point is rotated by all the rotating angles stored in the table, the sum of the angles by which the signal point has been rotated so far is outputted as the phase of the input signal point. <IMAGE></p> |
