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Radio Frequency Integrated Circuit Design - Webs

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Mixers<br />

Figure 7.20 Sidebands in upconversion, image in downconversion.<br />

Figure 7.21 A single-sideband mixer.<br />

an image reject mixer is formed. In this circuit, at the output, the RF signal<br />

adds in phase while the image adds in antiphase.<br />

7.10.1 Alternative Single-Sideband Mixers<br />

The image reject configuration in Figure 7.22 is also known as the Hartley<br />

architecture.<br />

Another possible implementation of an image reject receiver is known as<br />

the Weaver architecture, shown in Figure 7.23. In this case, the phase shifter<br />

after the mixer in Figure 7.22 is replaced by another set of mixers to perform<br />

an equivalent operation. The advantage is that all phase shifting takes place<br />

only in the LO path and there are no phase shifters in the signal path. As a<br />

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