Statistical characterization of RF power amplifier efficiency for CDMA wireless communication systems

Power amplifier (PA) efficiency for wireless communication systems is universally calculated at maximum output power. While this method has evolved into the de-facto efficiency figure-of-merit, it ignores the system effect on the average output power, and cannot in general provide an accurate estimate of the PA impact on phone talk-time. A more meaningful efficiency estimate is its long-term mean based on the statistics of the phone output power in a typical environment. This new efficiency characterization method provides an improved estimate of the PA impact on phone talk-time by including the efficiency variation of the PA output power, not the maximum average output power. A summary of the new efficiency characterization method is given, with two examples each for the IS-95 CDMA system and the AMPS system.