Patent ID: 8213893
Filing Date: 2012-07-03
Classification: H03D

Abstract:
1. A quadrature mixer arrangement for converting a first signal at a first frequency to a second signal at a second frequency, the arrangement having a first mixer operatively coupled to a first and a second radio frequency (RF) terminal and a second mixer coupled in parallel with the first mixer and operatively coupled to the first and second RF terminal, wherein the first mixer is arranged to mix the first signal with a first mixing signal to provide the second signal; and the second mixer is arranged to mix the first signal with a second mixing signal, whichs is out of phase with the first mixing signal, to provide the second signal, wherein the first mixer comprises: a first mixing means and a first signal path switch operatively connected in series between the first RF terminal and a first intermediate frequency (IF) terminal of the first mixer, wherein the first mixing means of the first mixer is arranged to be controlled by the first mixing signal and the first signal path switch of the first mixer is arranged to be controlled by the second mixing signal; and a second mixing means and a second signal path switch operatively connected in series between the first RF terminal and a second IF terminal of the first mixer, wherein the second mixing means of the first mixer is arranged to be controlled by the inverse of the first mixing signal and the second signal path switch of the first mixer is arranged to be controlled by the inverse of the second mixing signal; and the second mixer comprises: a first mixing means and a first signal path switch operatively connected in series between the first RF terminal and a first IF terminal of the second mixer, wherein the first mixing means of the second mixer is arranged to be controlled by the second mixing signal and the first signal path switch of the second mixer is arranged to be controlled by the inverse of the first mixing signal; and a second mixing means and a second signal path switch operatively connected in series between the first RF terminal and a second IF terminal of the second mixer, wherein the second mixing means of the second mixer is arranged to be controlled by the inverse of the second mixing signal and the second signal path switch of the second mixer is arranged to be controlled by the first mixing signal; whereby short circuits between said IF terminals of the first mixer and said IF terminals of the second mixer via the first RF terminal are prevented.