ULTRA-WIDE BAND OPTOELECTRONIC MICROWAVE MIXER FOR PHASED ARRAY RADAR

A COMBINATION OF OPTOELECTRONICS AND MMIC TECHNOLOGY HAS BEEN CITED AS A MUST FOR IMPLEMENTATION OF FUTURE PHASED ARRAY RADAR SYSTEMS WHERE TENS OF THOUSANDS OF ELEMENTS ARE INVOLVED. AN IMPORTANT ELEMENT IN SUCH SYSTEMS IS WIDE BAND MIXERS. SINCE THE MICROWAVE SIGNALS ARE CARRIED IN OPTICAL FORM, IT IS HIGHLY DESIRABLE TO PERFORM THE FUNCTION OF RF MIXING IN OPTICAL FORM WITHOUT HAVING TO FIRST CONVERT IT BACK TO AN ELECTRICAL SIGNAL. ULTRA-WIDE BAND MIXING CAN BE DONE USING HIGH SPEED PHOTOCONDUCTOR TECHNOLOGY THAT OFFERS BANDWIDTHS OF OVER 10GHZ. WE PROPOSE TO STUDY THE MIXER OPERATION AT MULTI-GIGAHERTZ FREQUENCIES AS WELL AS IMPLEMENTING PHOTOCONDUCTIVE MIXERS THAT OPERATES AT 1.3 MICROMETER OPTICAL WAVELENGTH, SUITABLE FOR USE WITH 1.3 MICROMETER HIGH SPEED LASERS AND ULTRA-LOW LOSS SINGLE MODE OPTICAL FIBERS.