Chirp signal analysis with amplitude modulation

Gheorghe Gavriloaia; Catalin Neamtu; Mariuca-Roxana Gavriloaia

doi:10.1117/12.970378

1 November 2012 Chirp signal analysis with amplitude modulation

Gheorghe Gavriloaia, Catalin Neamtu, Mariuca-Roxana Gavriloaia

Proceedings Volume 8411, Advanced Topics in Optoelectronics, Microelectronics, and Nanotechnologies VI; 84112R (2012) https://doi.org/10.1117/12.970378
Event: Advanced Topics in Optoelectronics, Microelectronics, and Nanotechnologies 2012, 2012, Constanta, Romania

Abstract

Signals with linear frequency modulation are used in synthetic aperture radar to improve spatial resolution and signal/noise ratio. Acoustic field is proposed in this paper to investigate objects, because it could penetrate them, and propagate inside. When input signal frequency is about resonance frequency, the attenuation is increased, and as a result, the scattered acoustic field is decreased as well. So, a linear frequency modulation signal with constant amplitude is sent to the investigated object, and variable amplitude is reflected, corresponding to the object resonance frequencies. A new method for detection the amplitude modulation of these signals in presence of noise is presented. The method uses the fractional Fourier transform in two steps. In the first step a rotation of signal by the angle=45⁰ is done. The all spectral components outside central band are canceled. After that a new rotation of new function with the same angle is done. The simulated results are presented. The method gives good results of amplitude modulation detection for signals with complex modulation signals having signal - noise ratio in power up to - 5 dB. By knowing the resonance frequencies it is possible to specify the largest 3D object dimension, appreciate the relative values of the other dimensions, and do a rough classification of that object. The presented method could be used for rough classification of buried objects in earth or to early diagnose whether a tumor tissue is or not malignant.

Citation Download Citation

Gheorghe Gavriloaia, Catalin Neamtu, and Mariuca-Roxana Gavriloaia "Chirp signal analysis with amplitude modulation", Proc. SPIE 8411, Advanced Topics in Optoelectronics, Microelectronics, and Nanotechnologies VI, 84112R (1 November 2012); https://doi.org/10.1117/12.970378

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available