| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce side lobe noise in a correlation processing system of an optical code modulation pulse. <P>SOLUTION: When a receiving signal of continuous light whose shift is reduced to the same degree as a Brillouin frequency shift of an optical fiber 1 by an optical frequency shifter 12, to which Brillouin amplification is performed by acoustic waves to be generated by interference between the continuous light and pump light modulated by a complementary correlation code modulation signal from a correlation code system signal generator 13 by an optical modulator 3 in the optical fiber 1 is processed, a result obtained by performing mutual correlation processing between A1(t)g(t) obtained by multiplying difference signal ΔRA1(t) between a response signal RA1(t) by a complementary correlation code system signal A1(t) and A1<SP POS="POST">-</SP>(t) obtained by exchanging elements of the complementary correlation code system signal A1(t) and RA1<SP POS="POST">-</SP>(t) by a reciprocal number g(t) of a step response function h(t) to correct attenuation of the acoustic waves is synthesized with a result obtained by similarly performing mutual correlation processing between B1(t)g(t) obtained by multiplying a difference signal ΔRB1(t) between a response signal RB1(t) by a complementary correlation code system signal B1(t) and B1<SP POS="POST">-</SP>(t), and RB1<SP POS="POST">-</SP>(t) by g(t). <P>COPYRIGHT: (C)2012,JPO&INPIT |
