A method of generating a BOC correlation function based on partial correlation functions, an apparatus for tracking a BOC signal, and a spread spectrum signal receiver system using the same are disclosed herein. The apparatus includes a frequency offset compensation unit, a local code generation unit, a mixer, a delay lock loop (DLL), a phase lock loop (PLL), and a data extraction unit. The frequency offset compensation unit outputs a compensated received signal with respect to a received signal. The local code generation unit generates a delay-compensated local code based on a code delay value. The mixer mixes the delay-compensated local code with the frequency offset-compensated received signal. The DLL repeatedly tracks and calculates a code delay value. The PLL repeatedly calculates a carrier frequency compensation value. The data extraction unit extracts spreading data from a mixture of the delay-compensated local code and the compensated received signal.

Code generating including generating a non-correlation sequence for RS of a first resource block; spreading spectrums of elements in the non-correlation sequence for RS to be mapped to a first frequency resource of the first resource block, by using a first group of codes; second spreading spectrums of elements in the non-correlation sequence for RS to be mapped to a second frequency resource of the first resource block, by using a second group of Codes; the first and second frequency resources are adjacent frequency resources in frequency resource elements used for RS transmission in the first resource block, and the first and second groups of Codes are mirrors in column to each other; and mapping the spectrum-spread elements to the first and second frequency resources, respectively.

Code generating including generating a non-correlation sequence for RS of a first resource block; spreading spectrums of elements in the non-correlation sequence for RS to be mapped to a first frequency resource of the first resource block, by using a first group of codes; second spreading spectrums of elements in the non-correlation sequence for RS to be mapped to a second frequency resource of the first resource block, by using a second group of Codes; the first and second frequency resources are adjacent frequency resources in frequency resource elements used for RS transmission in the first resource block, and the first and second groups of Codes are mirrors in column to each other; and mapping the spectrum-spread elements to the first and second frequency resources, respectively.