Title:
送信機及びそのための電力増幅器
Document Type and Number:
Japanese Patent JP3556973
Kind Code:
B2
Abstract:
A transmitter comprises a linearised power amplifier circuit (18) consisting of a power amplifier output stage (28) having a feedback loop (34) connected between its output (32) and input (30). The feedback loop (34) includes a coupler (56), a first gain control element (58) and a feedback function stage (64) which collectively determine the loop gain of the amplifier. A second gain control element (54) is provided in the forward gain path of the power amplifier (18). The first and second gain control elements (58,54) are controlled so that the product of their gains is constant. As a result the loop parameters remain substantially constant as the power setting is varied.
Inventors:
Jeffrey Sydney Sparks
Application Number:
JP18816094A
Publication Date:
August 25, 2004
Filing Date:
August 10, 1994
Export Citation:
Assignee:
Sepra Limited
International Classes:
H03G3/20; H03C3/08; H03D7/16; H03F1/32; H03F3/20; H03G3/10; H03G3/30; H03G5/16; H04B1/04; H04L27/36; (IPC1-7): H03G3/30; H03F1/32; H03F3/20; H03G3/10; H04B1/04
Domestic Patent References:
| JP63121326A | ||||
| JP5175743A |
Attorney, Agent or Firm:
Kosaku Sugimura