Group Project in Integrated Radio Frequency and Analog Design
This year, most students worked on parts aimed at a wireless
LAN system, building low-noise amplifiers, mixers, oscillators
and power amplifiers. The chosen frequency of operation was at
5.2 GHz, as in 802.11A, or 2.4 GHz as in 802.11B/G. Two students
built broadband amplifers, one aimed at the cable TV band from
50 to 900 MHz, the other from 1 GHz to 2 GHz. All design was
done in a SiGe BiCMOS process in which the ft of the bipolar
transistor was about 50 GHz. Most simulations were done using
Cadence software (Analog Artist, Spectre, etc)
This year, students were combined from the groups of Prof. Plett
and Prof. Rogers. A total of 13 students worked on this project.
Parts were:
Low-Noise Amplifier (LNA),
2.4 GHz,
5.2 GHz,
cascode
folded cascode.
Broadband Amplifier (LNA),
50-900 MHz,
1-2 GHz
mixer
Voltage-Controlled Oscillators (VCO) ,
2.4 GHz,
5.2 GHz,
Colpitts common-base,
Colpitts common collector,
negative Gm
Power Amplifier (PA),
Steps:
The first step was to explain the overall system to allow students
to choose their own block.
Background research in which the students learn about the
process, principles of the particular system being designed,
RF design procedures and techniques.
Then design of the individual blocks, first reviewing what
others have done (previous students at Carleton and designers
elsewhere) then one or several designs will be chosen and detailed
design will be done on individual blocks. Design includes:
design at the schematic level
simulation of the schematic design
circuit layout
post layout extraction of parasitics (capacitance)
comparison of layout versus schematic (LVS)
post layout simulation
interface with neighboring blocks and overall simulation.