Patent ID: 6766157
Filing Date: 2004-07-20
Classification: H03D

Abstract:
A quadrature downconverter for a direct conversion receiver, said downconverter comprising:an RF input element configured to provide at least first and second RF inputs; at least first and second quadrature splitters configured to receive said at least first and second RF inputs respectively, and to provide at least first and second in-phase RF outputs and at least first and second quadrature RF outputs; a local oscillator operating to provide at least first and second reference signals, each reference signal having an in-phase reference output and a quadrature reference output; and at least two sets of mixers, each set having at least first and second mixers, said first mixers of each mixer set modulating said first and said second in-phase RF output with said in-phase reference output respectively to produce in-phase baseband signals, and said second mixers of each mixer set modulating said first and said second quadrature RF output with said quadrature reference output respectively to produce quadrature baseband signals, where said at least first and second quadrature splitters and said reference outputs cooperate to substantially reduce any local oscillator leakage signal leaking into said RF input element.