Title:
SPREAD SPECTRUM RADIO COMMUNICATION DEVICE
Document Type and Number:
Japanese Patent JP2591401
Kind Code:
B2
Abstract:
PURPOSE: To make the S/N in modulation excellent and to stabilize the frequency of an FM modulating means by setting a specific carrier frequency and imposing spread modulation while maintaining synchronism between spread codes and an FM modulation carrier.
CONSTITUTION: A multiplier 9 multiplies the angle-modulated wave of an angle modulating circuit 52 by the N1-multiplication output of a local oscillator 49. Further, a multiplier 2 multiplies the output generated by dividing the frequency of the angle-modulated wave by a local oscillation output. The output of the multiplier 2 has its frequency divided by a frequency divider 26 to generate the spread codes by a PNG 48, the output of the multiplier 9 is multiplied by them, and SS modulation is imposed, so that the result is outputted. A multiplier 3 of a reception part, on the other hand, reversely spreads the SS signal and a multiplier 31 multiplies the signal by the multiplication output of the local oscillation output. A circuit 61 imposes angle demodulation on the output, frequency dividers 28 and 29 divides the frequency of the output generated by dividing the frequency of the output of a VCO 22 and multiplying the result by the local oscillation signal, and a PNG 47 generates a spread signal from the outputs of a synchronism detecting circuit 60 and a selecting circuit Sw. Consequently, the S/N in the modulation is made excellent and the frequency is stabilized.
Inventors:
ISHIGAKI YUKINOBU
Application Number:
JP13600492A
Publication Date:
March 19, 1997
Filing Date:
April 28, 1992
Export Citation:
Assignee:
VICTOR COMPANY OF JAPAN
International Classes:
H04B1/707; H04B1/7073; H04J13/00; (IPC1-7): H04B1/707
Domestic Patent References:
| JP6340422A |