A low-current Ku-band GaAs monolithic image rejection down-converter

A single-chip image rejection downconverter has been designed, fabricated. and tested for broadcast satellite receivers operating in the 11.7- to 12.2-GHz range. The downconverter consists of an RF low-noise amplifier (LNA), a filter-type image rejection mixer (IRM), and an intermediate frequency amplifier (IFA). It receives 11.7- to 12.2-GHz RF signals and down converts to 1.0- to 1.5-GHz IF signals with an external local oscillator. Since the filter integrated on the downconverter produces an image rejection of more than 30 dB, the downconverter requires no off-chip circuits for the image rejection. A conversion gain of 37+or-1 dB and a noise figure of less than 3.5 dB have been achieved over the RF frequency range. The current dissipation is only 40 mA, and the chip size is 2.8 mm*2.8 mm*0.45 mm.<
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