Industrial Technology Research Institute

Accton Technology Corporation

Chieh-Ho Lee

Chung-Ju Chang

Chung Hsin Lu

Methods and apparatuses for a closed-loop power control in a code-division multiple-access communication system wherein both received signal quality and communication channel quality are used to determine appropriate transmitter power, and transmission may be suspended when a channel quality metric, such as by short-term fading, degrades below a preset minimum threshold, or when a commanded transmitter power exceeds a preset maximum threshold, and wherein the transmitter power is controlled to mitigate fading effects so that received signal quality metric, such as by the average received signal power or by the average received SIR over a control cycle, approaches a preset desired level, and by momentarily suspending a remote terminal, overall system capacity and throughput may be enhanced.

Closed-loop power control method for a code-division multiple-access cellular system

An apparatus and method is provided for controlling transmission power levels of respective mobile stations in a wireless cellular system, wherein the signal is transmitted from a transmitter at a controlled power level so that either the average received power level or the average signal to interference ratio (SIR) at receiver is close to a desired level so that the desired signal quality is achieved. According to a first embodiment, the desired level for the average received signal power is calculated based on the ensemble average intercell interference power level and the desired SIR levels. According to a second embodiment, the received average SIR level is estimated based on the average desired signal power and the ensemble average interference power. The average received power level (average SIR value) is compared to the desired level to generate a power control command. The power control command is fed back to the mobile station to instruct the adjustment of transmission power of the mobile station.

Growing community of inventors

Hsinchu, Taiwan

Chieh-Ho Lee