Patent ID: 6778514
Filing Date: 2004-08-17
Classification: H04B

Abstract:
A method for recognition of a reference signal in a signal having M signal components (M&gE;2), the method comprising:receiving a signal s(t) that may contain a reference signal s(t;ref); providing an MÃ—M covariance matrix R of the M received signal components, and providing M selected eigenvector solutions V=Vj and associated eigenvalue solutions &lgr;=&lgr;j (j=1, 2, . . . , M) of the matrix relation RÂ·V=&lgr;V; selecting a subspace Sâ€² spanned by a selected subset of the vectors Vjâ€² (jâ€²=1, . . . , N(s)), with N(s) a selected number that is &lE;M; forming and integrating a product signal s(t)Â·Vjâ€²(t) over a selected time interval, t0&lE;tâ€²&lE;t, to form an estimation signal xjâ€²(t) for each of jâ€²=1, . . . , N(s); and using the estimation signal xjâ€²(t) and the reference signal s(t;ref) to determine a weighting coefficient wjâ€²(t) (jâ€²=1, . . . , N(s)), using a selected weighting criterion, and forming a sum signal y&af;(t)=&Sum;jâ€²=1N&af;(s)&it;wjâ€²&af;(t)&CenterDot;Vjâ€²&af;(t);â€ƒ&it;andas an estimate of the reference signal contribution to the received signal.