A High Performance Downconverter MMIC for DBS Applications

Young YUN  Takeshi FUKUDA  Taketo KUNIHISA  Osamu ISHIKAWA  

IEICE TRANSACTIONS on Electronics   Vol.E84-C   No.11   pp.1679-1688
Publication Date: 2001/11/01
Online ISSN: 
Print ISSN: 0916-8516
Type of Manuscript: PAPER
Category: Microwaves, Millimeter-Waves
downconverter MMIC,  DBS,  MODFET,  noise figure,  low LO power,  

Full Text: PDF>>
Buy this Article

In this work, using 0.2 µm GaAs modulation doped FET (MODFET), a high performance downconverter MMIC was developed for direct broadcasting satellite (DBS) applications. The downconverter MMIC showed a noise figure of 4.3 dB which is lower by 5 dB than conventional ones, and required only a low LO power of -10 dBm for normal DBS operation. At a low LO power of -10 dBm, the power consumption was 175 mW, which is lower than 50 percent of conventional ones. The frequency response of conversion gain exhibited a low gain ripple of 0.9 dB, and the LO leakage power was suppressed to a lower value than -30 dBm under a LO input power of -10 dBm. The fabricated chip exhibited a small size of 0.840.9 mm2. The objectives of this work are to improve the traditional direct broadcasting satellite (DBS) downconverters by an efficient circuit design and to describe the techniques employed in the design.