FREQUENCY OFFSET COMPENSATION SYSTEM

摘要

PURPOSE: To compensate a frequency offset with high accuracy over a wide lock range without the need for an AFC even conduction of quasi- synchronization detection in an on-land mobile communication QAM. CONSTITUTION: A reception section of a system adopting a transmission line distortion compensation system of pilot symbol insertion form applies quasi- synchronization detection to a reception signal. A pilot symbol detection section 18 detects a pilot symbol from a reception base band signal subject to quasisynchronization detection. A frequency compensation section 12 allows a changeover section 19 to select an initial value detection section 22 at first and the initial value detection section 22 calculates an initial value of phase fluctuation attended with a frequency offset. After the initial value is calculated, the changeover section 19 selects a phase detection section 20, in which a phase fluctuation in the pilot symbol is observed and a phase rotation section 21 rotates a phase of the reception base band signal in an opposite direction in matching with the phase fluctuation so as to realize compensation of the frequency offset.