A subharmonic mixer that has two switching stages is used to improved mixer gain in a direct downconversion receiver. The first switching stage mixes a received RF signal to an intermediate frequency that is one-half the received RF signal frequency. The second switching stage mixes the intermediate frequency to baseband. By connecting the two switching stages in series, current is reused and harmonic content from the first stage is fed into the second stage thereby improving the mixer gain.
Patent No. 7,616,937 Issued on Nov. 10, Assigned to Samsung Electronics for Subharmonic Mixer (South Korean Inventors)
Nov 11, 2009; ALEXANDRIA, Va., Nov. 17 -- Seong-soo Lee and Heung-bae Lee, both of Suwon-si, South Korea, Yong-hun Kim of Seoul, South Korea,...