Patent ID: 7274727
Filing Date: 2007-09-25
Classification: H04B,H04L

Abstract:
1. A circuit for detecting a shifted frequency, comprising: a path selection unit for measuring a delay profile of a spread signal that has passed through a plurality of paths, and searching and selecting an optimum path from among said plurality of paths; a plurality of finger processing units for reverse spreading the spread signal of each path, which is allocated by said path selection unit, by a spread code replica, obtaining a channel estimated value including at least phase variation component with respect to said path by using a given pilot symbol that is included in the signal after the reverse spread, and carrying out coherent detection by using said channel estimated value; a phase difference measuring unit for measuring a phase difference from each phase variation component by each of said finger processing units; a path timing difference measuring unit for measuring a periodical path timing difference depending on said delay profile; a frequency error detecting unit for detecting a frequency error of said signal by using said path timing difference and said phase difference; and a Doppler frequency detecting unit for detecting a Doppler frequency on the basis of said frequency error.