Analysis of Direct-Conversion IQ Transmitters With 25% Duty-Cycle Passive Mixers

Author

Mirzaei, Abdolreza ; Murphy, Damian ; Darabi, Hooman

Author_Institution

Broadcom Corp., Irvine, CA, USA

Volume

58

Issue

10

fYear

2011

Firstpage

2318

Lastpage

2331

Abstract

The performance of direct-conversion IQ transmitters with 25% duty-cycle passive mixers is analyzed. The up-conversion transfer function is calculated and it is shown that due to lack of reverse isolation of the passive mixer, the high- and low-side conversion gains can be different. The contribution of thermal noise from mixer switches to the total output noise of the transmitter is formulated. It is also revealed that the up-conversion of the baseband signal to higher order harmonics places more stringent linearity requirements on the post-mixer driver.

Keywords

mixers (circuits); switches; thermal noise; transfer functions; transmitters; baseband signal; direct-conversion IQ transmitter analysis; duty-cycle passive mixers; higher order harmonics; low-side conversion gains; mixer switches; post-mixer driver; thermal noise; up-conversion transfer function; Baseband; Harmonic analysis; Mixers; Noise; Radio frequency; Transfer functions; Transmitters; 25% duty-cycle; Direct-conversion; linearity; noise; passive mixer; transfer function; transmitter;

fLanguage

English

Journal_Title

Circuits and Systems I: Regular Papers, IEEE Transactions on

Publisher

ieee

ISSN

1549-8328

Type

jour

DOI

10.1109/TCSI.2011.2142790

Filename

5771077