Patent ID: 7542504

Claim:
method for performing frequency hopping Orthogonal Frequency Division Multiple Accesses (OFDMA), comprising the steps of: a) allocating frequency domain signals X(k) of a comb pattern to a modulated data sequence, X(k) being comb symbols and k being a frequency index; b) performing frequency hopping so that the comb symbols could have an independent frequency offset; and c) performing inverse Fast Fourier Transform (iFFT) on the comb symbols to be transformed to time domain signals x(n) and transmitting, using a transmitter, the time domain signals x(n), n being a time index, wherein the comb symbols formed of a predetermined number of sub-carriers, which is called a sub-carrier group, are positioned on an entire usable frequency band at predetermined intervals and the number of subcarriers on the entire usable frequency is expressed as: N = ∑ i N c ⁢ ⁢ N si = N C * N S , ( N si = N s = Const . ) where N C denotes the number of comb symbols that can be allocated in the entire usable frequency band; N si denotes the number of sub-carriers within an i th comb symbol, the size of the i th comb symbol, or the size of a sub-carrier group constituting the i th comb symbol, and X N c , i , q ⁡ ( k ) = { ≠ 0 , k = p i ⁢ N C + q i = 0 , ⁢ Otherwise ⁢ ⁢ { p i = 0 , 1 , … ⁢ , N si - 1 q i = 0 , 1 , … ⁢ , N C - 1 ; and wherein, in the step b), frequency hopping is performed on comb symbols X a,b (k) allocated to the mobile station in the cell according to a frequency indicator function Y a,b (k;l), which is a frequency hopping pattern and expressed as: Y a,b ( k;l )== X a,b (( k+P ( l ))mod N ) where P(l) (0≦P(l)≦N) is a frequency hopping pattern of comb symbols within a cell in a time slot 1 ; and N denotes the entire number of sub-carriers.