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Design And Characterization Of A 1-Watt Driver Amplifier For Wireless Infrastructure, Chin-Leong Lim
Design And Characterization Of A 1-Watt Driver Amplifier For Wireless Infrastructure, Chin-Leong Lim
Chin-Leong Lim
Variable gain amplifiers (VGA) find application in RF systems wherever the signal amplitude must be varied in reaction to a changing environment. Transmitters' driver stage utilize VGAs to conserve power under good propagation conditions and to minimize interference to adjacent sites. Cellular base-station receivers use VGAs in the 2nd/3rd stage LNA to prevent mixer/DAC overloading. Commercially available L-band VGA devices require 14 to 19 external components and have modest linearity-to-power consumption ratio (OIP3 / Pdc). To achieve the industry's lowest component count and best linearity-to-power ratio, we developed a highly integrated VGA module from 0.25 x 3900 um enhancement-mode Pseudomorphic …
Mass-Market Designed-For-Cellular Mmics Can Be Gainfully Adapted For Use In Niche Applications On Different Frequencies, Chin-Leong Lim
Mass-Market Designed-For-Cellular Mmics Can Be Gainfully Adapted For Use In Niche Applications On Different Frequencies, Chin-Leong Lim
Chin-Leong Lim
Due to semiconductor manufacturers’ near exclusive focus on high growth markets such as cellular and wireless data, very little commercial RND resource is expended on developing Microwave Monolithic Integrated Circuits (MMIC) for the lower-volume traditional wireless services such as aviation and land mobile, etc. To circumvent the dearth of MMICs in those under-served market segments, we intend to show how off-the-shelf cellular MMICs can be leveraged into non-cellular applications. For this purpose, a MMIC originally conceived as a 900 MHz 0.5W driver amplifier is redeployed to two dissimilar applications: (i) a high linearity Low Noise Amplifier (LNA) for the 400~520 …