Transmission power amplifier unit

• US 20060040625A1
• Filed: 10/25/2005
• Published: 02/23/2006
• Est. Priority Date: 09/30/1999
• Status: Abandoned Application

• Current Assignee: Ayanori Matsuda, Yutaka Saito
• Original Assignee: Ayanori Matsuda, Yutaka Saito
• Inventors: Matsuda, Ayanori, Saito, Yutaka
• Application Number:
  US11/257,917
• Publication Number:
  US 20060040625A1
• Time in Patent Office: Days
• US Class Current: 455/127.100
• CPC Class Codes: H03F 1/32 Modifications of amplifiers to reduce non-linear distortion by negative feedback H03F1/34
• CPC Class Codes: H03F 1/3229 using a loop for error extraction and another loop for error subtraction
• CPC Class Codes: H03F 1/3247 using feedback acting on predistortion circuits H03F1/3264 takes precedence
• CPC Class Codes: H03F 1/3282 Acting on the phase and the amplitude of the input signal
• CPC Class Codes: H03F 2200/105 A non-specified detector of the power of a signal being used in an amplifying circuit
• CPC Class Codes: H03F 2201/3233 Adaptive predistortion using lookup table, e.g. memory, RAM, ROM, LUT, to generate the predistortion
• CPC Class Codes: H03G 3/3042 in modulators, frequency-changers, transmitters or power amplifiers transmission power control in bidirectional transmission systems H04W52/04
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04W 52/52 using AGC [Automatic Gain Control] circuits or amplifiers

Abstract

A transmission power amplifier unit of a base-station apparatus for compensating for non-linear distortion of a transmission power amplifier by feed-forward control is provided with a gain varying unit for varying gain of the transmission power amplifier unit. At start-up of the transmission power amplifier unit, a controller determines whether the base-station apparatus is in a blossoming mode or breathing mode, maximizes gain of the transmission power amplifier unit by controlling the gain varying unit if the mode is the blossoming mode and increases the gain gradually in proportion to the passage of time if the mode is the breathing mode.

Claims

1. A base station provided with a transmission power amplifier unit, which has a main amplifier and a sub-amplifier, for compensating distortion of the main amplifier by feed-forward control using a signal output from the sub-amplifier, comprising:

a controller for controlling a gain of the transmission power amplifier unit to be constant at a predetermined value in a blossoming mode, wherein in the blossoming mode cell radius is enlarged at a fixed rate by increasing gradually a level of a signal input to the transmission power amplifier unit, from a value below a set level.

2. A base station according to claim 1, further comprising:

a gain varying unit for varying gain of the transmission power amplifier unit, wherein the controller determines whether the base-station apparatus is in the blossoming mode or breathing mode and increases the gain of the transmission power amplifier unit gradually if the mode is breathing mode.

3. A base station according to claim 1, wherein said controller includes:

a detection circuit provided in an input section of the transmission power amplifier unit for detecting input power; and

means for discriminating mode based upon whether said input is equal to or greater than a threshold level.

4. A base station according to claim 1, wherein said controller includes:

a detection circuit provided in an output section of the transmission power amplifier unit for detecting output power; and

means for discriminating mode based upon said output power value.

5. A base station according to claim 1, wherein the controller controls the gain of the transmission power amplifier unit to be constant at the predetermined value in the blossoming mode by fixing an amount of attenuation of a variable attenuator provided in said transmission power amplifier unit.