Design and measurement of Band V WCDMA LNA utilizing design kit with scalable parametric cell inductors

摘要

A low-noise amplifier (LNA) integrated circuit (IC) has been designed and implemented on a 0.13μm RF CMOS process technology. The performance of the LNA has been targeted to exceed WCDMA standard specification. This paper presents the design methodology and compares the simulated and measurement results of the cascode LNA with inductive degeneration. There were expected mismatch between simulation and measurement data, thus some of the matching elements were intentionally placed outside of the chip. Additionally, target frequency on simulation was designed at a general 850MHz frequency but later on measurement the target frequency was moved close to the center of receive frequency of Band V of WCDMA. On the simulation, at resonance frequency of 850MHz the NF is 0.54dB, 1dB input compression point is −26.67dBm and S21 is 27.86dB. On measurement where impedance matching were done exactly as in simulation with the exception in value of quality factor Q of the external passive devices, the NF about 2dB, 1dB input compression point is −25.3dB and S21 is 18dB at 875MHz. Value of LS and LG were adjusted to move peak of S21 to be at almost the new target frequency of 881.5MHz. Measurement result after impedance was matched to the band V receive center frequency, S21 has dropped to 13.37dB, NF has jumped to 2.65dB but linearity improved where 1dB input compression point has increased to −18.14dBm mainly because the drop in S21.