Design of a Direct-conversion Radio Receiver Front-end in CMOS Technology
Independent thesis Basic level (professional degree)Student thesis
In this Master's thesis, a direct-conversion receiver front-end has been designed in a 0.18um CMOS technology.
Direct-conversion receivers (DCR) have obvious advantages over the heterodyne counterpart. Since the intermediate frequency (IF) is zero, the problem of image is circumvented. As a result, no front-end image reject filter is required and the channel selection requires only a low-pass filter, which makes it easy to integrate directly on chip. However, the DCR also suffers from several drawbacks such as extreme sensitivity to DC offsets, 1/f noise, local oscillator (LO) leakage/radiation, front-end nonlinearity and I/Q mismatch. This implies very high demands on the DCR front-end.
The front-end comprises a low-noise amplifier (LNA) and a mixer. Different LNA and mixer architectures has been studied and from the mentioned inherited problems with direct conversion, one proposal for a solution is a differential source degenerated LNA and a differential harmonic mixer, which has been designed and simulated.
The LNA has a gain of 12dB, a noise figure of 3.6dB and provides a return loss better than -15dB. The overall noise figure of the signal path is 8dB and the overall IIP3 and IIP2 is -12dBm and 31dBm, respectively.
Place, publisher, year, edition, pages
Institutionen för teknik och naturvetenskap , 2002. , 41 p.
Electronics, Direct-conversion, Radio receiver, Front-end, CMOS, LNA, Mixer, Low-noise amplifier, Harmonic mixer.
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:liu:diva-1197ISRN: LITH-ITN-ED-EX--02/23--SEOAI: oai:DiVA.org:liu-1197DiVA: diva2:18357