Design Of FSK Laser Ranging Hardware System

In the laser distance measurement method,phase method laser ranging is widely adopted due to its long distance measurement and high accuracy.The existing single frequency phase method laser ranging can not take into account both the ranging accuracy and ranging range index,while the traditional dual frequency Phase method due to the need for multiple measurements and each measurement environment is different,anti-interference ability is poor.In this paper,FSK laser ranging method,the low frequency as the FSK side frequency signal,the high frequency as the FSK side frequency signal is a better dual-frequency phase laser ranging,this article will be based on this ranging method on the FSK laser Ranging hardware system design.In this paper,FSK laser ranging hardware system module is divided into FSK generator circuit,FSK receiver circuit and FSK phase measurement circuit of the three modules in the entire FSK laser ranging circuit to make full use of programmable logic device FPGA flexible,reliable,high-speed As the whole FSK laser ranging logic timing control,in the FSK part of the direct output by the FPGA three signal source,the local oscillator signal source design section,to provide all the way to the local oscillator signal source,and the quadrature signal source AD9854 dual channel In the configuration,in the phase measurement circuit,an internal phase measurement digital circuit is integrated in the FPGA to measure the phase of the input signal.FSK transceiver circuit design,this article FSK circuit to overcome the larger signal delay DDS,circuit anti-interference ability is poor,a frequency of 2.5MHz on the side of the frequency 102.5MHz modulation cycle 1k Hz,switching time is short,the basic frequency range Consistent,low-distortion FSK signal.FSK receiving part of the design of a band-pass filter receiver circuit to achieve FSK on the side frequency of 2.5MHz and 102.5MHz weak signal extraction,and through the signal reduction circuit to complete dual-band FSK receive filtering.FSK phase measurement circuit design,the entire measurement circuit is divided into local oscillator output,frequency changes,filtering,integer circuit design.The local oscillator 300 MHz DDS chip source provides local oscillator signal,AD834 high-speed analog multiplier for the FSK signal and local oscillator signal mixing,LM319 comparator for integer changes in the FPGA integrated digital phase measurement unit,in addition to the phase Measurement of the circuit itself and DC bias error caused by a good solution.FSK laser ranging circuit debugging,the actual application of the results of detection,to achieve high quality FSK signal transceiver,and expand the entire FSK laser ranging circuit design to make up for the current FSK laser ranging circuit scarcity.