| 摘要 |
PROBLEM TO BE SOLVED: To reduce power consumption in a network performing communication by use of very weak radio waves.SOLUTION: A telegraphic message generating unit 123 in a signal processing unit 12 generates a telegraphic message with the total of 18 bits made up of a 12-bit digital signal indicating sensor information from an ADC 121 and a 6-bit ID combined at the higher-order side of the digital signal. A telegraphic message dividing unit 124 divides the input 18-bit telegraphic message into higher-order 2 bits and lower-order 16 bits. A spread code determination processing unit 125 determines 4 kinds of spreading codes with the use of the higher-order 2 bits supplied by the telegraphic message dividing unit 124. A frequency determination processing unit 126 determines a frequency value of "1" with the use of the higher-order side 8 bits of 16 bits supplied by the telegraphic message dividing unit 124 and a frequency value of "0" with the use of the lower-order side 8 bits referring to a frequency table stored in a memory 122. A frequency switching unit 127 generates a frequency change signal according to an input spread signal and a frequency value, and supplies it to a radio communication unit 13. |
