scholarly journals Optimized Combination of Local Beams for Wireless Sensor Networks

Sensors ◽  
2019 ◽  
Vol 19 (3) ◽  
pp. 633
Author(s):  
Semyoung Oh ◽  
Young-Dam Kim ◽  
Daejin Park
Keyword(s):  
Signal To Noise Ratio ◽  
Wireless Sensor ◽  
Linear Arrays ◽  
Wave Channel ◽  
Average Improvement ◽  
Simulation Results ◽  
Noise Ratio ◽  
The Given ◽  
Single Objective ◽  
Average Interference

This paper proposes an optimization algorithm to determine the optimal coherent combination candidates of distributed local beams in a wireless sensor network. The beams are generated from analog uniform linear arrays of nodes and headed toward the random directions due to the irregular surface where the nodes are mounted. Our algorithm is based on one of the meta-heuristic schemes (i.e., the single-objective simulated annealing) and designed to solve the objective of minimizing the average interference-to-noise ratio (INR) under the millimeter wave channel, which leads to the reduction of sidelobes. The simulation results show that synthesizing the beams on the given system can form a deterministic mainlobe with considerable and unpredictable sidelobes in undesired directions, and the proposed algorithm can decrease the average INR (i.e., the average improvement of 12.2 dB and 3.1 dB are observed in the directions of π 6 and 2 π 3 , respectively) significantly without the severe loss of signal-to-noise ratio (SNR) in the desired direction.

scholarly journals An Algorithm for Automatic Recogniton of Digital QAM Modulations

2019 ◽  
Vol 25 (3) ◽  
pp. 36-41
Author(s):  
Alexandru-Daniel Luţă ◽  
Paul Bechet
Keyword(s):  
Lower Order ◽  
Signal To Noise Ratio ◽  
Recognition Rate ◽  
Automatic Recognition ◽  
Signal To Noise ◽  
Small Influence ◽  
Qam Modulation ◽  
Digital Modulations ◽  
Simulation Results ◽  
Noise Ratio

Abstract This paper proposes a new Matlab-developed algorithm for automatic recognition of digital modulations using the constellation of states. Using this technique the automatic distinction between four digital modulation schemes (8-QAM, 16-QAM, 32-QAM and 64-QAM) was made. It has been seen that the efficiency of the algorithm is influenced by the type of modulation, the value of the signal-to-noise ratio and the number of samples. In the case of an AWGN noise channel the simulation results indicated that the value of SNR (signal-to-noise ratio) has a small influence on the recognition rate for lower-order QAM (8-QAM and 16-QAM). The length of the signal may change essentially the recognition rate of this algorithm especially for modulations with a high number of bits per symbol. Consequently, for the 64-QAM modulation in a case of 25dB signal-to-noise ratio the recognition rate is doubled if the sample rate is incresed from 5400 to 80640.

A Fast Block-Matching Motion Estimation Method Based on Difference Search Algorithm

2014 ◽  
Vol 610 ◽  
pp. 686-694
Author(s):  
Chang Jiang Liu ◽  
Chao Chen ◽  
A Fei Zhang ◽  
Xiao Lang Yan
Keyword(s):  
Motion Estimation ◽  
Search Algorithm ◽  
Signal To Noise Ratio ◽  
Estimation Method ◽  
Block Matching ◽  
Signal To Noise ◽  
Estimation Algorithms ◽  
Diamond Search ◽  
Simulation Results ◽  
Noise Ratio

The diamond search (DS) algorithm is one of the most efficient block matching motion estimation algorithms by far and has already been applied in MPEG2/4. Through our research, we found that there is still some redundancy in the algorithm. In this paper, an improved new difference based search (DBS) algorithm is proposed. Simulation results demonstrate that the new algorithm outperforms the well-known diamond search (DS) algorithm and four step-searches (4SS). It obtains almost the same Peak Signal to Noise Ratio (PSNR) while requires less computations than the DS algorithm and 4SS algorithm.

Automatic Variable K Module Design of Digital Phase-Locked Loop

2012 ◽  
Vol 263-266 ◽  
pp. 20-24
Author(s):  
Yan Peng Sun ◽  
Xia Yu Yang
Keyword(s):  
Signal To Noise Ratio ◽  
Phase Locked Loop ◽  
High Signal ◽  
Signal To Noise ◽  
Module Design ◽  
Digital Phase ◽  
Capture Time ◽  
Simulation Results ◽  
Noise Ratio

PLL lock signal, there is contradictions in the capture time and capture bandwidth, also in the capture bandwidth and high signal-to-noise ratio. The article adopted the method of timely change bandwidth to resolve these conflicts, and used the VHDL to design a auto-change K module to adjust the bandwidth. Simulation results verify the validity of the module in the side of resolving conflicts between capture time and capture bandwidth, and capture bandwidth and high signal-to-noise ratio too.

scholarly journals SNR improvement based on piecewise linear interpolation

2021 ◽  
Vol 72 (5) ◽  
pp. 348-351
Author(s):  
Pengfei Xu ◽  
Yinjie Jia
Keyword(s):  
Signal To Noise Ratio ◽  
Piecewise Linear ◽  
Linear Interpolation ◽  
Signal To Noise ◽  
Piecewise Linear Interpolation ◽  
Snr Improvement ◽  
Simulation Results ◽  
Noise Ratio

Abstract Interpolation improves the resolution of the curve. Based on the stationary characteristics of the signal and the non-stationary characteristics of the noise, the theoretical proof indicates that the piecewise linear interpolation can improve the signal-to-noise ratio, which is further confirmed by simulation results.

scholarly journals Bipolar Digital Logic Local Oscillator for Bitstream Photon Counting Chirped AM Lidar

2019 ◽  
Author(s):  
Brian Redman
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Signal To Noise Ratio ◽  
Photon Counting ◽  
Local Oscillator ◽  
Digital Logic ◽  
Quantization Noise ◽  
Signal To Noise ◽  
Simulation Results ◽  
Noise Ratio

This paper is a follow-up to a previous paper introducing the new bitstream Photon Counting Chirped Amplitude Modulation (AM) Lidar (PC-CAML) with a Digital Logic Local Oscillator (DLLO) concept. In that previous work, the DLLO was unipolar. In this paper, a new bipolar DLLO for the bitstream PC-CAML is introduced (patent pending). The bipolar DLLO retains the key advantages of the unipolar DLLO for the bitstream PC-CAML since it also replaces bulky, power-hungry, and expensive wideband RF analog electronics with digital components that can be implemented in inexpensive silicon complementary metal-oxide-semiconductor (CMOS) read-out integrated circuits (ROICs) to make the bitstream PC-CAML with a DLLO more suitable for compact lidar-on-a-chip systems and lidar array receivers than previous PC-CAML systems. In addition, the bipolar DLLO improves the electrical power signal-to-noise ratio (SNR) of the bitstream PC-CAML by about 2.5 dB compared to that of the unipolar DLLO as shown by the theoretical and Monte Carlo simulation results presented in this paper. Theoretically, there should be a 3 dB improvement for the bipolar DLLO from the elimination of the signal power loss to the DC component of the intermediate frequency (IF) spectrum that occurs with the unipolar DLLO. However, this improvement is partially offset by a higher quantization noise for the bipolar DLLO compared to that of the unipolar DLLO as explained in this paper.This paper introduces the bipolar DLLO for bitstream PC-CAML concept and presents the initial signal-to-noise ratio (SNR) theory with comparisons to Monte Carlo simulation results.

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