【摘 要】
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For the purpose of structural enhancement and backwards compatibility,more than two binary signals on one carrier frequency are required to emit.In order tomaximize the power efficiency,constant-envel
【机 构】
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SatelliteNavigationR&DCenter,NationalUniv,of Defense Technology,Changsha 410073,China
论文部分内容阅读
For the purpose of structural enhancement and backwards compatibility,more than two binary signals on one carrier frequency are required to emit.In order tomaximize the power efficiency,constant-envelope modulation isadopted.Alt-BOC and ACE-BOC modulations,the constant-envelope modulation thatmultiplexes four binary spreading codes as two QPSK signals at two different carrier frequencies,areproposed by Galileo and BeiDou respectively.A constraint of these new modulations is that thenumber of signals to be multiplexed must be no larger than four signal channels.In this paper,ageneralizeddual-frequency constant-envelope multiplexing technology,named generalized constant envelope BOC (GCE-BOC) modulation,is presented.The modulation can be regarded asthe extended form ofAlt-BOC and ACE-BOC modulations and provides asolution to dual-frequency constant envelope multiplexing problem for worldwide GNSS.
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