| 摘要 |
PURPOSE: A method for controlling a power of a CDMA(Code Division Multiple Access) communication system is provided to decrease a transmission error of a power control command by transmitting a power control command corresponding to a signal transmission interval and transmitting a previous power control command in a signal no-transmission interval. CONSTITUTION: A receipt signal intensity measuring unit of a BTS(Base Transceiver Station) measures an intensity of a signal transmitted from a terminal for judging whether it is a signal transmission interval(ST1). The BTS judges whether the measured value is more than a predetermined threshold value(ST2). If the measured value is not more than the predetermined threshold value, the BTS retransmits a previous power control bit(ST3). If the measured value is more than the predetermined threshold value, the BTS compares the measured value with a power control threshold value(ST4). If the measured value is less than the power control threshold value, the BTS transmits an 'up' command to a terminal(ST5). If the measured value is more than the power control threshold value, the BTS transmits a 'down' command to the terminal(ST6). A digital demodulator of the terminal outputs a demodulated signal(ST7) and extracts a power control bit from the output signal(ST8). The terminal judges whether it is the signal transmission interval(ST9). If it is not the signal transmission interval, majority principle is applied to power control bits received from the signal transmission interval to a current time(ST10). The terminal judges whether the number of 'up' bit is identical to the number of 'down' bit(ST11). If the number of 'up' bit is not identical to the number of 'down' bit, the terminal selects bits having the large number of bits and compares the number of selected bits with the sum of power control response received from the signal transmission interval to a previous time(ST12,ST13). If the number of selected bits is different from the sum of power control response, it is judged whether the power control bit is an 'up' or 'down' command according to the power control bit by the majority principle(ST14). If the power control bit is the 'up' command, a transmission power is increased by a designated level(ST15). If the power control bit is the 'down' command, the transmission power is decreased by the designated level(ST16). |
