TY - GEN
T1 - Front-end topologies for phased array radiometry
AU - Sonmez, M. K.
AU - Trew, R. J.
AU - Hearn, C. P.
PY - 1992
Y1 - 1992
N2 - There is interest in developing phased array radiometers for space based applications. The limitations and the optimum topology for beam forming network in radiometric systems, however, are not well understood. In this work, two phased array total power radiometer front end topologies are compared in terms of gain and noise temperature stability. It is shown that a phased array radiometer topology incorporating amplifiers at each branch reduces the front end gain and noise figure fluctuation. The dependence of the front-end gain fluctuation on the number of the elements in the array, N, is shown to be ▲G/G ∝ 1/√N. Thus, it is demonstrated that the gain fluctuation contribution of the front-end is reduced as the array size gets larger. This results in a larger maximum usable calibration interval under the condition that the gain variation effects not dominate radiometer ∝T. Such a system also has a lower noise temperature by virtue of the frontend amplification. This work indicates that total power phased array radiometers have significant potential for space based applications.
AB - There is interest in developing phased array radiometers for space based applications. The limitations and the optimum topology for beam forming network in radiometric systems, however, are not well understood. In this work, two phased array total power radiometer front end topologies are compared in terms of gain and noise temperature stability. It is shown that a phased array radiometer topology incorporating amplifiers at each branch reduces the front end gain and noise figure fluctuation. The dependence of the front-end gain fluctuation on the number of the elements in the array, N, is shown to be ▲G/G ∝ 1/√N. Thus, it is demonstrated that the gain fluctuation contribution of the front-end is reduced as the array size gets larger. This results in a larger maximum usable calibration interval under the condition that the gain variation effects not dominate radiometer ∝T. Such a system also has a lower noise temperature by virtue of the frontend amplification. This work indicates that total power phased array radiometers have significant potential for space based applications.
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U2 - 10.1109/euma.1992.335876
DO - 10.1109/euma.1992.335876
M3 - Conference contribution
AN - SCOPUS:0027043030
SN - 0946821879
SN - 9780946821877
T3 - Conference Proceedings - European Microwave Conference
SP - 1251
EP - 1256
BT - Conference Proceedings - European Microwave Conference
PB - Publ by Microwave Exhibitions & Publ Ltd
T2 - Proceedings of the 22nd European Microwave Conference
Y2 - 24 August 1992 through 27 August 1992
ER -