Patent ID: 7843388
Filing Date: 2010-11-30
Classification: G01S,H04L

Abstract:
1. An arrival direction estimation apparatus comprising: an antenna in which a plurality of antenna elements are symmetrically arranged centering on a given reference position or a reference line and which receives signals by the plurality of antenna elements; a complex digital signal converting means which converts the signals received by each antenna element of the antenna to complex digital signals; a real number correlation matrix calculating means which calculates a real number correlation matrix expressing correlation among the plurality of antenna elements of the complex digital signals; a real number weight matrix calculating means which calculates a real number weight matrix used for calculating a spectrum based on the calculated real number correlation matrix; a spectrum calculating means which calculates the spectrum based on the calculated real number weight matrix and a previously prepared real number matrix used for calculating the spectrum; and a spectrum peak detecting means which detects a direction with a peak value with the use of the calculated spectrum, wherein the spectrum calculating means includes a real number matrix storing means which stores the real number matrix, a multiplying means which multiplies part of elements of the real number matrix stored in the real number matrix storing means by part of elements of the real number weight matrix, a result storing means which stores a processing result of multiplication by the multiplying means, a calculating means which performs at least one or more processing of matrix element inversion processing and matrix element sign change processing for the processing result stored in the result storing means, an adding means which adds a processing result by the calculating means, part of the processing result stored in the result storing means, and part of the elements of the real number weight matrix, and a spectrum calculating means which calculates the spectrum with the use of a processing result by the adding means.