A method for controlling transmitter power for a CDMA message transmission system

A transmission power control method for a spectrum widening communication system which performs communication between a base station (203) and a plurality of mobile devices (204) using a plurality of channels, wherein: the plurality of channels first channels (3) which are assigned to the mobile devices, for transmitting a data packet to the base station, and a second channel (140), which is used by the base station to transmit a control signal to the mobile devices, wherein said is mobile devices share the second channel, the second channel (140) is a forward traffic channel; the base station measures the reception level of a signal that is received on each of the first channels, generates a transmission power control signal in accordance with the reception level of each of first channel and a common transmission power control signal containing the transmission power control signals for the respective first channels in a predefined for the system format into collected that inserts into the second channel and the common transmission power control signal containing the transmission power control signals for each of the first channels, transmits via the second channel; and each mobile device that assigned to him receives transmission power control signal on the second channel and the transmission power control for a corresponding one of the first channels to be transmitted signal in accordance with the received transmission power control signal.