The Design And Implementation Of10MHz-12GHz Ultra-wideband Receiver

In recent years wireless communications has made significant development.Moreand more attention is focused on the high-performance wireless communication whichhas tremendous applications in both the civilian and military fields.Besides the highsensitivity,high linearity performance of the modern wireless communicationreceivers,the demand to the wide band becomes higher and higher for each country. Inline with the development of the broadband receiver, this paper detail introduce the keymodules of the broadband receiver, and in allusion to its concrete structure which can berealized do a detailed theoretical analysis and research.The broadband receiver as theforefront of the receiving system,whose performance directly affect the workingcondition of the receiving system. The design and structure of the receiver is also verydifferent for different bands,different indicators. This paper is based on the requirementsof the specific indicators of the receiver, on the basis of the existing receiver structuretheory analysis to determine the overall program. And according to the level of theexisting devices and possession refine the program of the receiver and detailallocation.At last the details of the design process is given.The subject comes from the technical cooperation mission of the broadband downconversion.The operating frequency of the receiver is10MHz-12GHz,and the outputintermediate frequency(IF) is190MHz.To achieve the wide band receiving,thesuperheterodyne double-conversion scheme is been used to the receiver that the first IFfrequency is the high frequency and the second is the required IF.Because of a widefrequency band, to suppress mutual interference, down-conversion module is dividedinto six bands subsection receiving.The local oscillator module is divided into two localoscillators，the first local oscillator adopts the scheme of the phase-locked loop（PLL）interpolated by DDS (Direct Digital Synthesis) that provide the wideband small stepsignal. The second local oscillator is the single phase-locked loop that provides twofixed points frequency. Because the more demanding requirements of the receiver theanalysis of the scheme and the argument has its specific characteristics.First，the research background and the development of broadband receiver are introduced in this article,and the specific indicators of the receiver has been given. Thenthe detailed analysis is carried out to the down-conversion module and the frequencysource module of the receiver.At last,we give the test results for the receiver.