a comm system is disclosed which comprises mobile stations and a base station . the mobile station comprises ; a 1st receiving and transmitting portion ; a detection portion for detecting an electric power of a 1st desired wave component of the received 1st cdma sig ; a table for storing a relation between reception power and transmission power of a 2nd cdma sig to be transmitted ; a demodulation portion for demodulating the received 1st cdma sig and for detecting a cont sig in the desired wave ; a compensation portion for compensating the relation according to the detected cont sig ; and a transmission power cont portion for controlling a transmission power determined according to the electric power obtained through the compensated table and the reception power . the base station comprises ; a 2nd receiving and transmitting portion ; an power detection portion for repeatedly detecting an electric power of a 2nd desired wave component of the received 2nd cdma sig ; an averaging portion for averaging the repeatedly detected electric powers to obtain an average ; and a cont sig generation portion for generating the cont sig according to an error between the average and a given value . the relation is corrected within a portion of range of the reception power or within a range of transmission power .