Results 21 to 30 of about 1,015,748 (173)

ISAR Imaging of Non-Stationary Moving Target Based on Parameter Estimation and Sparse Decomposition

Remote Sensing, 2023
This paper studies the inverse synthetic aperture radar imaging problem for a non-stationary moving target and proposes a non-search imaging method based on parameter estimation and sparse decomposition.
Can Liu, Yunhua Luo, Zhongjun Yu, Jie Feng   +3 more
doaj   +1 more source

Chirp Signal Transform and Its Properties

Journal of Applied Mathematics, 2014
The chirp signal exp(iπ(x-y)2) is a typical example of CAZAC (constant amplitude zero autocorrelation) sequence. Using the chirp signals, the chirp z transform and the chirp-Fourier transform were defined in order to calculate the discrete Fourier ...
Mio Horai, Hideo Kobayashi, Takashi G. Nitta   +2 more
doaj   +1 more source

Exploiting Chirp Rate Estimation Methods to Improve Image Formation Quality of Synthetic Aperture Radar

International Journal of Aerospace Engineering, 2021
A common assumption in SAR image formation and processing algorithms is that the chirp rates of the transmitted and received radar signals are exactly the same. Dechirp processing is also done based on this common assumption. In real scenarios, the chirp
N. Rabiee, H. Azad, N. Parhizgar
doaj   +1 more source

M-ary nonlinear sine chirp spread spectrum for underwater acoustic communication based on virtual time-reversal mirror method

EURASIP Journal on Wireless Communications and Networking, 2021
Linear chirp spread spectrum technique is widely used in underwater acoustic communication because of their resilience to high multipath and Doppler shift.
Songzuo Liu, Habib Hussain Zuberi, Yi Lou, Muhmmad Bilal Farooq, Shahabuddin Shaikh, Waleed Raza   +5 more
doaj   +1 more source

Tracking and Mitigation of Chirp-Type Interference in GPS Receivers Using Adaptive Notch Filters [PDF]

, 2020
A Global Positioning System (GPS) receiver is extremely prone to intentional and unintentional interference due to weak signal power experienced on the surface of the earth, which severely affects the navigation functionality and occasionally avoids the ...
Syed Waqas Arif, Kale, I., Arif, S., Izzet Kale, Adem Coskun, Coskun, A.   +5 more
core   +1 more source

Robust Underwater Acoustic Communication Using the Overlapped Chirp Spread Carrier Technique in Doubly Spread Environments

IEEE Access, 2023
The performance of underwater acoustic communication is significantly affected by multipath propagation and Doppler spread. In this paper, we propose a new communication technique called overlapped chirp spread carrier (OCSC) by modifying the existing ...
Chang-Hyun Youn, Hyung-In Ra, Kyung-Won Lee, Ki-Man Kim   +3 more
doaj   +1 more source

rparnellturner/auv-chirp: v1.0.0

, 2022
Processing flow for CHIRP data collected by ...
Ross Parnell-Turner
core   +1 more source

A Controllable Suppression Jamming Method against SAR Based on Active Radar Transponder

Remote Sensing, 2022
A chirp-mismatch echo signal can be generated by exchanging the I and Q baseband signals of a received SAR signal. In this paper, the basic generation principles of a chirp-mismatch echo signal are analyzed.
Guikun Liu, Liang Li, Feng Ming, Xilong Sun, Jun Hong   +4 more
doaj   +1 more source

Multiuser chirp modulation for underwater acoustic channel based on VTRM

International Journal of Naval Architecture and Ocean Engineering, 2017
In this paper, an ascheme is proposed for multiuser underwater acoustic communication by using the multi-chirp rate signals. It differs from the well known TDMA (Time Division Multiple Access), FDMA (Frequency Division Multiple Access) or CDMA (Code ...
Fei Yuan, Qian Wei, En Cheng
doaj   +1 more source

VERSATILE CHIRP SINE GENERATOR ON FIXED-POINT FPGA

Acta Polytechnica, 2020
This paper deals with a logarithmic and a linear chirp sine generation on a fixed-point FPGA mainly for vibration testing, nevertheless, the generator can also be used in other areas.
Jan Kunz, Petr Beneš
doaj   +1 more source