| 摘要 |
PURPOSE:To simplify code deciding arithmetic by calculating rotationally a receiving signal in a coordinate system until a signal point of the receiving signal is included in a prescribed discrimination area. CONSTITUTION:A receiving signal 200 is developed as a signal point in a rectangular coordinate system consisting of an in-phase axis and a rectangular axis. An area decision part 202 decides whether the signal point of the signal 200 exists in the prescribed decision area of the coordinate system or not. When the signal point does not exist in the decision area, a counter 204 is counted up by +1 and the signal point of the signal 200 is rotated around the coordinates by a prescribed angle with a rotator 206. The area decision 202 is executed again and the operation is repeated until the signal point is included in the decision area. When the decision part 202 decides that the signal point is included in the decision area, the counted value of the counter 204 is read out. Consequently, a code decision part 208 decides that a position obtained by rotating the signal point reversely by the counted value is a point indicated by the receiving signal. |
