| 摘要 |
This invention relates to a bias voltage adjusting method of a power amplifier stage transistor of a base station and an electronic loop circuit, being designed to perform the steps of the bias voltage adjusting method. Such methods and circuits are used for efficiency improvement of power amplifier chains preferably within UMTS base stations, in general sending stages of broad band mobile communication systems. The inventive electronic loop circuit is comprising: decoupling means 10, being designed to decouple a fraction of a radio signal to be transmitted, an analogue/digital converter 14, being designed to convert said fraction of the radio signal to a digitalized signal, ACLR analysing means 16, being designed to perform an ACLR analysis of said digitalized signal by calculating an ACLR value from the digitalized signal, an ACLR optimiser 18, being designed to calculate a bias voltage value within ACLR requirements, a digital/analogue converter 20, being designed to convert said value to an analogue voltage and voltage applying means 22, being designed to apply said voltage to said transistor 5 as a bias voltage. <IMAGE> |
