Title :
Non-recursive FM demodulation of laser radar backscatter using time-frequency distributions
Author :
El-Dinary, Ashruf S. ; Cole, Timothy D.
Author_Institution :
Appl. Phys. Lab., Johns Hopkins Univ., Laurel, MD, USA
Abstract :
FM demodulation of noisy data suffers in output signal-to-noise ratio (SNR) performance due to the FM threshold for conventional bandpass/limiter FM discriminators. Our application of detecting and monitoring skin vibrations of a vehicle using a laser vibration sensor (LVS) requires the demodulation of potentially noisy data. We successfully implemented an FM demodulator based on estimation of instantaneous frequency through time-frequency distributions and achieved a 3-15 dB improvement in SNR performance. The LVS problem and demodulation approaches are described in this paper as well as results from simulated data and recorded LVS data. Processing time comparisons for different platforms are also discussed
Keywords :
backscatter; demodulation; demodulators; discriminators; frequency modulation; limiters; measurement by laser beam; optical radar; optical sensors; signal processing; statistical analysis; time-frequency analysis; vibration measurement; FM demodulator; FM threshold; SNR performance; bandpass/limiter FM discriminators; instantaneous frequency estimation; laser radar backscatter; laser vibration sensor; noisy data; non-recursive FM demodulation; output signal-to-noise ratio; platforms; processing time; recorded LVS data; simulated data; skin vibrations detection; skin vibrations monitoring; time-frequency distributions; Backscatter; Demodulation; Frequency estimation; Laser radar; Monitoring; Radar detection; Signal to noise ratio; Skin; Vehicle detection; Vehicles;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 1994. ICASSP-94., 1994 IEEE International Conference on
Conference_Location :
Adelaide, SA
Print_ISBN :
0-7803-1775-0
DOI :
10.1109/ICASSP.1994.390017
