| dc.description.abstract | The thesis focuses on the millimeter wave receiver front-end circuit designs, which include the low noise amplifiers in V band. The circuits are fabricated by WIN 0.15 um pHEMT and TSMC 0.18 um CMOS process.
Chips designed in this thesis include the low noise amplifier and distributed amplifier. The low noise amplifier is implemented by cascading three stages, the first two stage is designed for low noise while the last stage is matched for high gain. Except microstrip line, the transmission line also presents by finite-width ground coplanar waveguide. Finite-width ground coplanar waveguide has the benefits with simplifying the fabrication, facilitating easy shunt as well as series surface mounting of devices, and reducing radiation loss and suits for designing the route in microwave and millimeter wave circuit. The width of the ground line of the finite-width ground coplanar waveguide is simulated to gain the optimum circuit performance. On the other hand, the broadband amplifier is implemented using the topology of three-stage cascaded single stage distributed amplifier to obtain the maximum gain in per unit area.
The measured and simulated results of the designed circuits are illustrated as followings: for the V-band LNA at 50 GHz, the obtained small signal gain is 20.7 dB, input power at the 1-dB gain compression point is -15 dBm, simulated noise figure is 4.2 dB at 60 GHz; for V-band coplanar waveguide LNA at 50 GHz, the small signal gain is 22.17 dB, output power at the 1-dB gain compression point is -18 dBm, the simulated noise figure is 5.2 dB at 60 GHz; for the 20-35 GHz cascaded single stage distributed amplifier, the small signal gain is more than 5 dB with a bandwidth of 15 GHz where the peak gain is 12.1 dB at 20 GHz, input power at the 1-dB gain impression point is -10 dBm and -7 dBm at 20 GHz and 28 GHz, respectively; for the 26-65 GHz cascaded single stage distributed amplifier, the small signal gain is more than 16.5 dB with a bandwidth of 39 GHz, input power at the 1-dB gain impression point is more than -15 dBm. | en_US |