| 摘要 |
In an identification system based on reflection of radar signals from a bit-coded transponder, the received signals are processed to remove unwanted signals and noise from the required, reflected and received signals that have a recurrent cycle. The reflected signals are extremely weak in relation to the unwanted signals and noise. A random bit sequencer and a time slot generator are used to generate a single phase modulated pulse train which is transmitted by an RF transmitter. The pulse train signal is received and reflected from a coded passive transponder back to a comparable receiver. The receiver demodulates the incoming reflected signal and directs the demodulated signal to an integrator array. An inverted signal from the receiver is also utilized. Synchronization of the transmitted and received signals is performed through a shift register while the bit sequencer controls a second integrator array. In this way, the unwanted signals and noise associated with the low power reflected signal is substantially eliminated.
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