| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a spectrum diffusion distance-measuring apparatus whose distance- measuring accuracy and distance-measuring resolution are enhanced and which reduces an interference from other vehicles by a method wherein the one-chip time width of a pseudo noise(PN) code is set at the time or higher required at a time when light makes a round trip of a maximum detection distance. SOLUTION: A transmission PN code is output from a PN code generator 102 which is driven by a clock oscillator 101 at a transmission part 1, and it is converted into a light signal by an electricity/light converter 103 so as to be radiated toward an object. However, the one-chip time width of the transmission PN code is set at the time or higher required at a time when light makes a round trip of a maximum detection distance. The light signal which is radiated from the converter 103 is reflected by the object, and its reflected signal is received by a light/electricity converter 201 at a reception part 2. A signal which is converted into an electric signal by the converter 201 is input to a matched filter 202 as a reception PN signal. The matched filter 202 comprises the pattern of the reception PN code, and it finds a correlation between a preset PN code and the reception PN code so as to output a correlation signal.</p> |
