DocumentCode
277270
Title
Wideband modulator for high switching speed frequency synthesiser
Author
Cotton, F.J. ; Buck, B.J. ; Fryers, A.J.
Author_Institution
GEC-Marconi Mater. Technol. Ltd., Towcester, UK
fYear
1992
fDate
33718
Firstpage
42370
Lastpage
42374
Abstract
This paper describes a single sideband suppressed carrier modulator intended to produce fine frequency stepping on the output of a broadband synthesiser, operating from below 1 GHz to greater than 5 GHz. The digitally synthesised local oscillator in the 100-200 MHz range is in principle also capable of working broadband. The modulator consists of a 90° coupler, a hybrid of 5 GaAs MMICs and a Si 400 MHz direct digital frequency synthesiser. The GaAs hybrid contains 2 active 180° splitters, 2 balanced FET mixers and a combining amplifier. An output of 0 dBm is obtained from the modulator with better than 20 dB rejection of the unwanted carrier and sideband
Keywords
III-V semiconductors; MMIC; frequency synthesizers; gallium arsenide; hybrid integrated circuits; mixers (circuits); modulators; 1 mW; 1 to 5 GHz; GaAs; Si; balanced FET mixers; combining amplifier; coupler; fine frequency stepping; frequency synthesiser; high switching speed; local oscillator; single sideband suppressed carrier modulator; splitters; wideband modulator;
fLanguage
English
Publisher
iet
Conference_Titel
Active and Passive Components for Phased Array Systems, IEE Colloquium on
Conference_Location
London
Type
conf
Filename
168272
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