Patent ID: 8780956

Claim:
A method for determining a smooth window length in channel estimation the method comprising: obtaining autocorrelation values of pilot signals, wherein the autocorrelation values comprise at least two first autocorrelation values and at least one second autocorrelation value wherein the autocorrelation values of the pilot signals are autocorrelation values in non-zero correlation intervals; determining a speed range according to symbols of the first autocorrelation values or according to the symbols of the first autocorrelation values and a ratio value between the second autocorrelation value and one of the first autocorrelation values; and determining the smooth window length according to the speed range; wherein a calculation formula for obtaining the autocorrelation values of the pilot signals is as follows: R ⁡ ( k ) = ∑ f = 1 M ⁢ ⁢ R f ⁡ ( k ) wherein R(k) is the autocorrelation value of the pilot signal, k is a correlation interval and not equal to 0, M is the preset number of multi-path search periods, and R f (k) is an autocorrelation value of a pilot signal within a multi-path search period of an index f , and the calculation formula of R f (k) is as follows: R f ⁡ ( k ) = ∑ t = 1 L mpsf ⁢ ⁢ ∑ j = 1 N f ⁢ ⁢ { Re ⁡ [ A j ⁡ ( t - k ) × A j * ⁡ ( t ) ] } wherein L mpsf is the number of pilot channel time slots contained in the multi-path search period of the index f, N f is the number of effective paths in the multi-path search period of the index f, Re( )is an operation for taking a real part, A* j is a conjugate function of A j (t), A j (t) is an accumulated value of the antenna separation values of the pilot signals within each time slot, and a calculation formula of A j (t) is as follows: A j ⁡ ( t ) = ∑ i = 1 N / 2 ⁢ ⁢ A i , j ⁡ ( t ) wherein N is the number of pilot signal symbols within each time slot, A i,j (t) is an antenna separation value of a pilot signal of an index i corresponding to a path of an index j within a time slot of an index t.