GILBERT UPCONVERSION MIXERS USING SINGLE-BAND/DUAL-BAND LC CURRENT COMBINERS

摘要

The 0.35-μm SiGe BiCMOS high linearity Gilbert upconverters are demonstrated in this article by utilizing NMOS and PMOS transconductance amplifiers (TCAs), respectively. To improve the linearity of a Gilbert upconverter, the IF input TCA is replaced by a biasoffset differential pair. A reactive LC current combiner is used as the load of the Gilbert mixer to double the output current. The upconverter with an NMOS TCA achieves the conversion gain of -4 dB, the OP{sub}(1dB) of -11 dBm, and the OIP{sub}3 of 5.5 dBm, whereas the other one with a PMOS TCA has the conversion gain, OP{sub}(1dB), and OIP{sub}3 of -6 dB, -11 dBm, and 9.5 dBm, respectively. Furthermore, the LC current combiner can be extended to a dual-band version. The 2.4/5.7 GHz dual-band upconverter is also demonstrated in this work. The conversion gain at 2.4/5.7 GHz is -3/-3.5 dB with the OP{sub}(1dB) of -15.5/-15 dBm and the OIP{sub}3 of -2.5/-3 dBm, respectively.