| 摘要 |
PURPOSE:To extend the transmission distance while reducing the data error by a method wherein a PN code generated from a transmission station is modulated and transmitted by radio and a narrow band signal received at a receiving station is demodulated thus detecting the phase of the PN code. CONSTITUTION:A transmission station comprises a GNSS(Global Navigation Satellite System) receiver 10T, a sync clock generating section 14T, a P/S converting section 16T, and a frequency converting/modulating section 18T. The frequency converting/modulating section 18T modulates a local oscillation signal of predetermined frequency with a PN code fed from the P/S converting section 16T and increases the frequency of the local oscillation signal up to a radio frequency before it is fed to a power amplifying section 20T. The power amplifying section 20T power amplifies the modulated wave and transmits the amplified wave to a neighboring receiving station from a ground antenna 24T. The receiving station recevies a signal from a GNSS satellite using a GNSS antenna 22 and the modulated wave from the transmitting station is received by a ground antenna 24R and amplified at a high frequency amplifying section 20R. It is then fed through a frequency converting/demodulating section 18R to an S/P converting section 16R. |
