By Dr. Thomas M. Straus, Hughes Aircraft Company
The recent development of the Hughes A ML ® Microwave Line Extender block upconversion type multichannel transmitter provides additional options for the CATV system designer. To optimize the overall system, it is necessary to understand both the capabilities and limitations of this new type of AML transmitter. Power output may be traded off against composite triple beat. Secondarily, transmitter gain and noise need be considered with regard to desired triple beat performance. The impact of the microwave subsystem tradeoffs on the overall CATV system must also be taken into consideration since the block upconversion type microwave system is not nearly as "transparent" as the standard AML system. When these factors are properly evaluated, the all solid state, outdoor mounted AML Line Extender transmitter can provide attractive solutions to various CATV system design problems. Several recent implementation examples are described.