The present invention relates to a method for encoding a signal of a wireless communication system, the method comprising dividing a current frame of the signal into a plurality of GOBs (Groups of Blocks) each having a certain size, determining whether a current GOB to be encoded of the plurality of GOBs is a first GOB of the current frame, calculating a control parameter value of the current GOB according to whether the current GOB is the first GOB of the current frame, controlling an encoding bit rate of the current GOB according to the control parameter value, and encoding the current GOB. Preferably, a hybrid method wherein an inter-frame GOB update method and an intra-frame GOB update method is used, so that a bit rate change between frames is reduced and data transmission of a channel is efficiently made to therefore provide a user with optimum image quality.