L.A. Abramov - Ph.D. (Eng.), Leading Expert, JSC «Russian Institute of Radionavigation and Time», St.-Petersburg. E-mail: alaspb@mail.ru
S.P. Zarubin - Head of Department, JSC «Russian Institute of Radionavigation and Time», St.-Petersburg. E-mail: zarubin@rirt.ru
N.S. Khokhlov - Head of Laboratory, JSC «Russian Institute of Radionavigation and Time», St.-Petersburg. E-mail: hohlov_ns@rirt.ru

The long range pulse-phase radio navigation systems (PPRNS), Russian «eChayka» and foreign «eLoran», are recognized as the best reserve systems for global navigation satellite systems (GNSS). The possibility of designing a high power radio transmitter for PPRNS based on transistors and with forming radio pulses directly in antenna is considered. Antenna circuit is connected to the generator of sequence of alternating rectangular video pulses with different voltages. As the video pulses generator a set of series-connected bridge high frequency generators with a transformer in the bridge diagonal is used. Input voltage of the antenna circuit is set stepwise by changing a number of simultaneously switched-on generators. The presented calculation method allows to perform exact, without using of numerical methods, calculation of required power PPRNS radio transmitter based on the given analytically or tabular current radio pulses form in antenna.

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