Selective limited feedback method for cooperative multicast transmission system

The invention discloses a selective limited feedback method for a cooperative multicast transmission system. Therefore, a problem of high costs on average feedback in the prior art can be solved by utilizing the method provided in the invention. The method comprises the following steps that: (1) a sub-codebook is generated by utilizing random vector quantization and is also stored to a to-be-served user terminal and a cooperative base station end; (2), a to-be-served user obtains a downlink channel vector through channel estimation; (3), the to-be-served user carries out codebook selection on the downlink channel vector so as to obtain corresponded a code word sequence number; (4) the to-be-served user calculates a signal to noise ratio of a single-link channel gain; (5), the to-be-served user make comparison between the signal to noise ratio and a preset signal to noise ratio threshold value; if the signal to noise ratio is less than the preset signal to noise ratio threshold value, the to-be-served user does not feedback the corresponded code word sequence number; if the signal to noise ratio is not less than the preset signal to noise ratio threshold value, the to-be-served user feedbacks the corresponded code word sequence number; and the signal to noise ratio threshold value is set according to an average feedback cost required by the system. According to the invention, codebook connection is utilized as the basis; and limited feedback and selective feedback are combined, so that average feedback costs can be substantially reduced.