Patent ID: 6334050
Filing Date: 2001-12-25
Classification: H03G

Abstract:
A radio unit for communication with radio terminals comprising:at least one remote transmitter amplifier unit having an input and an output, wherein the input of the transmitter amplifier unit is connected to a transmitter-and-receiver unit in the radio unit by a feeder having time-varying attenuation, wherein the output of the transmitter amplifier unit is connected to an antenna unit, wherein the transmitter amplifier unit includes a first variable amplifier;a second variable amplifier having an input and an output, wherein the output of the second variable amplifier is connected to said transmitter-and-receiver unit via said feeder, and wherein the input of the second variable amplifier is connected to said antenna unit;at least one sensor means for generating a detector signal corresponding to the signal output power of said antenna unit;a difference amplifier for comparing said detector signal with a reference signal corresponding to a desired signal output power, wherein a difference signal is obtained on an output of the difference amplifier, and wherein the output of the difference amplifier is connected at least to said first variable amplifier, and wherein said difference signal is used to control said first variable amplifier to compensate for said varying attenuation in the feeder; andat least one remote receiver amplifier unit having an input and an output, wherein the input of the receiver amplifier unit is connected to said antenna unit, wherein the output of the receiver amplifier unit is connected to the transmitter-and-receiver unit in the radio unit via said feeder, wherein said receiver amplifier unit includes said second variable amplifier, and wherein said difference signal controls the second variable amplifier to compensate for said varying attenuation in said feeder.