The Microwave Solid-State Power Amplifiers Technologies & Appling In SAR Systems

The microwave power amplifier plays a role in synthetic aperture radarsystems. It amplifies linear frequency modulation signals from the low power level tothe power level that systems demand. By contrast with single-carrier and multi-carriercommuni-cation systems' power amplifying, because of particularities of synthetic radarsystems and linear frequency modulation signals, amplifying linear frequencymodulation signals may bring forward some specific problems relating to SARsystems.The dissertation research pertinent technologies of power amplifiers designinginvolved by the numbers, across-the-abroad, in-depth, with an eye to apply to themicrowave solid-state power amplifiers in SAP, systems. It contains biasing circuitsdesigning techniques, stability designing techniques, matching network designingtechniques, the linearization designing techniques and heat, electromagnetism compati-bility as well as amplifiers cavity structure designing techniques.It is well known that, single microwave solid-state power amplifier can not satisfytransmitting power level of SAR systems heretofore. Based on, this dissertationintroduces power combine techniques of microwave solid-state power amplifiers formeeting SAR systems transmitting power level. It covers binary system powercombine techniques, parallel feed-in power combiner techniques, serial feed-in powercombine techniques and mixing power combine techniques.The most direct mode of proving power amplifiers touching target or not istesting indexes one by one by way of instruments and meters measuring. So, thisdissertation put forward testing methods of key techniques indexes of poweramplifiers with respect to SAR systems consanguineous. It includes the testing of pulse phase linearity, pulse phase noise, inter-pulse noise, phase excursion of carrierand heat-state output VSWR.The dissertation analysis roots of leading to key technique indexes distort fromcircuits principles, according as actual designing circuits of microwave solid-statepower amplifiers, at the same time, the distort function expressions are presented.Also analysis effects of pulse compression of SAR systems linear frequencymodulation signals deriving from all distorts indexes quantificationally, and advancemeasures or ways reducing distorts of some indexes.