FIELD: radio engineering.
SUBSTANCE: method of increasing the range of a multisubscriber radio frequency identification system relates to radio engineering and can be used in organization of identifying several objects simultaneously. Novel in the method of multisubscriber radio frequency identification is that transponders are included mounted on identification objects of single-port radio frequency amplifiers and controllable transmission-type phase shifters. With transponders antennae radio-frequency oscillations from the reading device are received and passed for the first time through the controllable transmission-type phase shifter. After that the radio-frequency signal is amplified with the single-port amplifier, where its additional amplitude modulation is performed with a unique code sequence. Amplified and modulated radio-frequency signal is again passed through the controllable transmission-type phase shifter, to the control input of which a low-frequency control signal is delivered, and then emitted via the transponder antennae. Double passage through the phase shifter leads to a frequency shift of the radio-frequency signal. With the reading device antenna transformed by frequency and amplitude-modulated radio-frequency oscillations are secondarily received and mixed with the initial radio-frequency oscillations, as the result of which at the output of the mixer several signals from the transponders are obtained simultaneously, herewith those combinatorial low-frequency components of the difference of initial and transformed by frequency radio-frequency oscillations are identified. Selected in each channel of the reading device low frequencies are equal to shift frequencies introduced by every transponder within the operational range of the radio frequency identification system.
EFFECT: each of those low-frequency signals is demodulated and simultaneously at the output of amplitude detectors several unique code sequences are obtained, thereby providing identification of several objects simultaneously.
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