for example the inventive method can be applied to the ues 408 410 430 and the like as shown in fig3 moreover according to 3gpp document ts36 213 v9 1 0 u201c physical layer procedures u201d for a downlink lte system with a bandwidth of 20 mhz there are around 96 spectral resource blocks in the frequency domain in addition to a control signaling area each of the spectral resource blocks consisting of 12 sub carriers and 14 ofdm symbols according to a definition these spectral resource blocks are sorted in a ascending order in terms of frequency every eight consecutive spectral resource blocks are referred to as a sub band thus there are around 12 sub bands it is to be noted that the above definition of sub band which is compliant with standardized protocols is exemplified for explaining the embodiments of the present invention the application of the present invention is not limited to the above definition and is fully applicable to other definitions by reading the embodiments of the present invention those skilled in the art can understand that the solution of the present invention is applicable to a general definition of sub band fig4 is a flowchart illustrating a csi feedback method according to the present invention as shown in fig4 the csi feedback method according to.