FIELD: radio-engineering, communication.
SUBSTANCE: method of secret information transmission by the object means emission of the electromagnetic energy, where object is exposed by receiving-transmitting antennal (RTA1) of radar station (RS1)by continuous signal with frequency modulation under one-side saw-toothed linear law (NLFM signal) that is received by RTA2 of RS2 of the object, directed via two channels, and in one channel NLFM signal is delayed for time tz, and in another channel it passes through the coder generating different NLFM radio pulses with different width corresponding, for example, to dot, hyphen and pause from Morse alphabet, then NLFM signals are summed, reinforced as per power. And via RTA2 are re-transmitted towards RS1, where they are multiplied with the emitted LNLFM signal for further separation at RS1 of two signals with frequencies: Fpi=2DiFmdfm/C±2Vif/C and Fpj=2DiFmdfm/C±2Vif/C+B, where C and Vi are light velocity and speed of approach or divergence of RS1 and RS2; f, Fm and dfm are frequency, modulation frequency and frequency deviation of NLFM signal; B is part of frequency of difference signal due to delay of NLFM signal; Di is distance between radar , and separation of definite difference Δ=Fpi-Fpj=B upon which identification it is assumed that the object transmits the secret information.
EFFECT: expansion of assortment of devices used for information transmission.
2 cl
Authors
Dates
2015-04-20—Published
2014-02-04—Filed