Patent ID: 7599978

Claim:
A method of decimating a digital signal, x(n), where n is an integer, the method comprising: generating the digital signal, x(n), as part of a radio communication process; determining a signal vector, y(k), of size M by partitioning samples of the digital signal, x(n) according to sampling phases of the samples, wherein each element of the signal vector, y(k), is a signal constructed with a same sampling phase; projecting the signal vector, y(k), onto an N-dimensional sub-space, wherein N is an integer and N<M; determining a covariance matrix R y , of the signal vector y(k); determining N eigen vectors corresponding to N greatest eigen values of the covariance matrix, R y , wherein the N-dimensional sub-space is spanned by the N eigen vectors; and determining an M×N or N×M matrix V, comprising the N eigen vectors, wherein the signal vector, y(k), is projected onto the N-dimensional sub-space in accordance with z ( n )= V H y ( n ) or z ( n )= y ( n ) V H , wherein V H is the Hermitian transpose of the matrix, V, and z(n) is a decimated signal.