Receiver and receiving method

A receiver for receiving a frame including a pilot signal and a data signal, referring to an impulse response of a propagation path estimated from the pilot signal, and performing compensation processing on the data signal, the receiver comprising:

• an extractor configured to extract the pilot signal of the frame;
• and
• an estimator configured to execute orthogonal matching pursuit (OMP) method which is a decoding algorithm for compressive sensing and to estimate the impulse response from the pilot signal,
• wherein the estimator refers to a pilot signal of a first frame, estimates an impulse response, determines position information on the estimated impulse response, refers to a pilot signal corresponding to the determined position information, of a second frame subsequent to the first frame, estimates an impulse response, and determines position information on the estimated impulse response;
• wherein each of the pilot signal is an N-dimensional signal vector in a time domain,
• wherein the estimator has a first matrix with N rows and K columns that represents a transformation between the N-dimensional signal vector and a K-dimensional impulse response vector indicating a time position of the impulse response,
• in execution of the OMP method,
• wherein the estimator executes first processing including:
• determining a column number of the first matrix, for which an inner product of the N-dimensional signal vector and a column component of the first matrix has a maximum,
• connecting a column vector for the column number in the first matrix to right side of 0 matrix so as to generate a second matrix, and
• estimating a provisional impulse response vector based on the second matrix and the N-dimensional signal vector,
• wherein the estimator repeatedly executes second processing including:
• determining a column number of the first matrix, for which an inner product of an exclusion N-dimensional signal vector and a column component of the first matrix has a maximum, the exclusion N-dimensional signal vector being obtained by excluding the already estimated provisional impulse response from the N-dimensional signal vector,
• connecting a column vector for the column number in the first matrix to right side of the second matrix so as to generate a new second matrix, and
• estimating a provisional impulse response vector based on the new second matrix and the exclusion N-dimensional signal vector,
• wherein the estimator estimates an impulse response based on the column number determined in the second processing and the provisional impulse response vector estimated in the second processing, and
• wherein each of N and K is an integer greater than or equal to 1.