Preceding the availability of high frequency, high gain and sufficiently low noise semiconductor transistors, the need to increase the radio receiver sensitivity as led to a concerted work among several research teams during the mid-fifties, . One of the objectives was to reduce the impact of the signal loss and noise added at the mixing stages. To achieve this goal, LNAs were developed, designed and inserted between the antenna and the mixer stage of a conventional receiver architecture. As a result, the equivalent receiver noise temperature, during that period, has reduced from 3,000 to 1,000 K when using traveling-wave tube, or to 10 K in the case of a MASER, [50, 51]
|Title of host publication||Parametric Analog Signal Amplification Applied to Nanoscale CMOS Technologies|
|Place of Publication||US|
|Publication status||Published - 1 Jan 2012|
Oliveira, J. P. A. D., Goes, J. C. D. P., & DEE Group Author (2012). Parametric Signal Amplification in Continuous Time Domain. In Parametric Analog Signal Amplification Applied to Nanoscale CMOS Technologies (pp. 33-52). US: Springer.