Maximum likelihood estimation of the channel coefficients and of the DC offset in a digital baseband signal of a radio receiver using the sage algorithm

A method for estimation of the channel coefficients (h0 . . . hL;

• θh) and of the DC offset (d;
• θd) in a digital baseband signal in a radio receiver using a training sequence, comprising:
• a) generating a received signal vector y from a number of received training sequence data symbols (y(k)) and a number of known training sequence data symbols (t(k));
• b) producing a maximum likelihood estimate of a function Λ(θ) which contains the channel coefficients (θh) and the DC offset (θd), in such a way that a first likelihood function Qh(θh;
• {circumflex over (θ)}′) is produced for the channel coefficients (θh), and a second likelihood function Qd (θd;
• {circumflex over (θ)}′) is produced for the DC offset (θd);
• and
• c) using the SAGE algorithm to produce a convergent sequence of expected values of the first and second likelihood functions Qh(θh;
• {circumflex over (θ)}′) and Qd (θd;
• {circumflex over (θ)}′), respectively, by means of at least one expected value determination step, and at least one maximization step with a parameter vector {circumflex over (θ)}′ comprising initial estimated values of the maximized values {circumflex over (θ)}h′ and {circumflex over (θ)}d′.