WIRELESS TELECOMMUNICATION TERMINAL FOR DETECTING LINEAR OUTPUT POWER

摘要

A mobile terminal having a linear output power detection function is provided to effectively control power of a CDMA mobile terminal and enhance characteristics of a nonlinear power detector by employing a log amplifier at a minimum cost. The first amplifier(21) amplifies a signal of a PCS frequency band. The second amplifier(22) amplifies a signal of a cellular frequency band. A coupler(23) couples a transmission signal transmitted through an RF terminal of a mobile terminal and splits it, or couples a reception signal received through the RF terminal of the mobile terminal and splits it. The first duplexer(24) separates a transmission signal and a reception signal from the signal of the PCS frequency band. The second duplexer(25) separates a transmission signal and a reception signal from the signal of the cellular frequency band. A diplexer(26) separates the signal of the cellular frequency band and the signal of the PCS frequency band. A power detector(27) detects power of the transmission/reception signal of the PCS frequency band or power of the transmission/reception signal of the cellular frequency band split by the coupler(23). A voltage/power converter(28) converts a voltage detected and outputted by the power detector(27) into a power form. A log amplifier(29) converts nonlinear power which has been converted by the voltage/power converter(28) into a linear voltage. An MSM(Mobile Station Modem)(30) controls output power of the mobile terminal by using the linear voltage.