Experimental and theoretical analysis of the relation between received signal power and signal to noise ratio of a heterodyne laser detection system
Abstract
The relation between received signal power and signal to noise ratio (SNR) of a continuous CO2 laser heterodyne detection system was investigated. The system is designed for range finding. Periodic amplitude modulation of the laser beam is applied. Calculations are performed for the relation between the heterodyne SNR of the received signal and the SNR of the cross correlation function obtained after envelope detection. Only additive noise is considered; the multiplicative noise which occurs as fluctuations of signal strength is not treated. The SNR and the standard deviation of the range of a number of objects were used to estimate the minimal discernable signal. The received signal power is determined by the SNR of the measured correlation function for objects at different ranges. The difference between this power and the estimated signal power calculated from the target range, the estimated reflection etc. is discussed.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- February 1983
- Bibcode:
- 1983STIN...8411495V
- Keywords:
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- Heterodyning;
- Laser Range Finders;
- Signal Reception;
- Signal To Noise Ratios;
- Carbon Dioxide Lasers;
- Cross Correlation;
- Electromagnetic Noise;
- Laser Target Designators;
- Lasers and Masers