Title:
RADIO TRANSMISSION EQUIPMENT
Document Type and Number:
Japanese Patent JP3537988
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To set an input signal level to a guadrature modulation circuit to be within a prescribed range and to operate a guadrature modulator with optimum precision by gain-controlling an input signal to the guadrature modulator.
SOLUTION: The result of vector multiplication of an antenna A is gain- controlled by a gain A1 in accordance with a gain control signal G1 from a gain controlled variable calculation circuit 104 in gain control circuits 105 band 106. The vector multiplication result of an antenna B is gain-controlled by a gain A2 in accordance with a gain control signal G2 in gain control circuits 107 and 108. The signals are converted into analog signals in D/A converters 109-112. Then, a guadrature modulator 113 orthogonally modulates the base band signal of the antenna A and converts in into an IF frequency S4. Then, a mixer 115 converts the IF frequency S4 of the antenna A into a transmission frequency signal and it is gain-controlled by a gain B1 in the gain control circuit 117 of a power amplifier. Then, it is transmitted from the antenna A.
Inventors:
Hiramatsu, Katsuhiko
Miya, Kazuyuki
Miya, Kazuyuki
Application Number:
JP9030697A
Publication Date:
June 14, 2004
Filing Date:
March 25, 1997
Export Citation:
Assignee:
MATSUSHITA ELECTRIC IND CO LTD
International Classes:
H01Q3/26; H04B7/06; H04B7/10; H04J13/00; H04L27/20; H04L27/36; (IPC1-7): H01Q3/26; H04J13/00; H04L27/20; H04L27/36