Information transmission

专利名称：Information transmission发明人：Hermann Sepp申请号：US05/625536申请日：19751023公开号：US04319358A公开日：19820309

摘要：The invention relates to information transmission systems in which the band isspread at the transmitting end by means of a pseudo- noise sequence and is returned tonormal at the receiving end by a similar sequence. In such systems it is essential that thefrequency of the various oscillators used for the frequency conversions should be keptconstant, or alternatively that the oscillators at the receiving end should be synchronizedwith the oscillators at the transmitting end. In accordance with the present invention theoscillators at the transmitting end are synchronized by the clock frequency of the codegenerator and at the receiving end this clock frequency is extracted from the receivedsignal and used to synchronize the oscillators in the various conversions. One of theoscillators at the receiving end may be a Gunn oscillator which is synchronized byapplying the output of the pulse generator to its synchronizing input terminal through afrequency multiplier. In another arrangement the frequency of the Gunn oscillator iscontrolled by comparing the phase of the output with the phase of the output of afrequency multiplier supplied by the pulse generator. In yet another arrangement theoutputs of the Gunn oscillator and the frequency multiplier are mixed to form adifference signal which is compared in phase with the outputs of a low frequencyreference oscillator.

申请人：SIEMENS AKTIENGESELLSCHAFT

代理机构：Hill, Van Santen, Steadman, Chiara & Simpson

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