Image rejection curcuit
AssigneeNiigata Seimitsu Co., Ltd.
InventorsTakashi Aoyama, Hiroshi Miyagi
Life of this patent
Estimating the term…
Abstract
In order to provide an image rejection circuit that can reject an image signal without being affected by manufacturing variations in circuit elements such as resistors, condensers, or the like, an image rejection circuit is provided which comprises a first mixer unit 2 for mixing a signal received by a receiver device with a first local oscillation signal generated by a local oscillator 1, a second mixer unit 3 for mixing the received signal with a second local oscillation signal obtained by shifting the local oscillation signal generated by the local oscillator 1 by 90°, a polyphase filter circuit 4 including condensers C1 and switched capacitors, and a composition/output unit 5 for composing and outputting the IF signals output from the polyphase filter circuit 4.
Claims3
An image rejection circuit comprising at least:
- a first mixer unit for mixing a received signal with a first local oscillation signal;
- a second mixer unit for mixing the received signal with a second local oscillation signal obtained by shifting the phase of the first local oscillation signal by 90°;
- a polyphase filter circuit which receives, as inputs to the polyphase filter circuit itself, a signal output from the first mixer unit and a signal output from the second mixer unit, and which includes a plurality of condensers and a plurality of switching elements;
- and
- a composition/output unit for composing and outputting a plurality of signals output from the polyphase filter circuit.
Dependencies are inferred from the claim text.