1/1/2024 0 Comments Audio tuner calibration![]() ![]() Among the bands on VIIRS are 14 reflective solar bands (RSBs). Partnership (NPP) spacecraft on October 28, 2011. The Visible-Infrared Imaging Radiometer Suite (VIIRS) was launched onboard the Suomi National Polar-orbiting A significant improvement in detection performance was observed for an antenna spacing of $hboxlambda$ however, to avoid degradation of antenna efficiency at such close spacing, proper impedance matching must be performed. It is observed that the detection performance of the linear array is directly related to the mean signal cross-correlation achieved by the array. This paper also investigates the effect of varying the antenna spacing on the received signal correlation and its subsequent effect on the detection performance. In the presence of noise calibration error (which is inevitable in a practical system), the maximum eigenvalue of the correlation matrix (MEC), Hadamard ratio test (HRT), and covariance absolute value (CAV) algorithms exhibit a significant improvement in detection performance as the number of antennas is increased, whereas the eigenvalue-based detection (EBD) algorithms show no improvement. Multiple antennas serve to enhance the received signal correlation, thereby causing an improvement in the detection performance of the CBD algorithms. Covariance-based detection (CBD) algorithms are applied to the received signals to perform blind signal detection. ![]() received signal strength and to cause variation in the incident angles of the incoming waves. The antenna array is moved in circular and linear paths to cause variation in. A software-defined-radio (SDR)-based receiver system is used to capture signals received by an antenna array while ensuring time and frequency synchronization across the radio-frequency (RF) front ends. In the paper several techniques for radar signal processing utilizing CLEAN concept are shown.Īn experimental investigation is reported on the use of a linear antenna array to perform blind signal detection. When only weak signals and white noise remains in is possible to use matched filter concept without significant loses of radar sensitivity. One of possible solution is to use concept of CLEAN technique an remove all strong echoes from received signal. The straightforward solution - use of inverse problem mathematical solutions such as solving the set of nonlinear equations to find all echoes in received signal - is usually computationally ineffective and often numerically not stable, so suboptimal methods are being developed to improve detections of weak signals in CW radars. In such radars all echoes are superimposed and interfere with each other and the simple model no longer fits to that case. The introduction of continuous wave radars, and especially noise and passive radars changed dramatically the situation. The introduction of pulse-compression technique changes significantly the signal model, but still the match filter have been widely. Such approach was effective when pulse radar have been widely used. The classical radar signal processing is based on match filtering concept, which is optimal in mean square sense in case, when single target echo is detected against white or colour Gaussian noise. Finally, we carry out the computational complexity analysis showing that the proposed method can be implemented with a minimal cost after some optimizations.Ī new class of signal processing algorithm based on CLEAN methods primary introduced in radio-astronomy is presented in the paper. We also provide the analysis of the Signal to Noise Ratio (SNR) during the detection of a moving target which shows that the proposed solution, based on symbol duplication, can offer around 3 dB of gain in SNR. We evaluate the performance of the proposed methods using real DAB signals acquired in an experimental PCL platform. We also demonstrate that two of these methods allow us to avoid the mentioned artifacts and thus to improve the quality of the range/Doppler plots with detection results. In this paper, we propose some methods of signal preprocessing (based on symbol removal, substitution by noise, and duplication) that operate on the DAB transmission frame level and improve the received signal’s correlation properties. However, extending the integration time in such a configuration leads to the occurrence of periodical artifacts in the bistatic range/Doppler plots, resulting from the time structure of the DAB signal. Digital Audio Broadcast (DAB) transmitters can be successfully used as illumination sources in Passive Coherent Location (PCL).
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |