scholarly journals Multitarget Position-Sensitivity Security Transmission with OAM-DM Based on FDA

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Changju Zhu ◽  
Maozhong Song ◽  
Xiaoyu Dang ◽  
Qiuming Zhu
Keyword(s):  
Digital Signal ◽  
Digital Transmission ◽  
Modulation Method ◽  
Transmission Scheme ◽  
Dual Mode ◽  
Intensity Pattern ◽  
Single Antenna ◽  
Position Sensitivity ◽  
Circular Frequency ◽  
Direction Information

The multitarget position-sensitivity security transmission scheme with orbital angular momentum (OAM) directional modulation (DM) waveform using the uniform circular frequency diverse array (FDA) is proposed. The transmitter employs FDA to generate dual-mode range-dependent OAM beam pattern, and the direction information of OAM beam is modulated into the signal. According to the modulation method, orthogonal carrier frequency can be designed to realize multitarget position-dependent OAM pattern. In the undesired position, the intensity pattern and the phase front of the radio beam vary randomly with the digital transmission sequence. Because modulation waveform is position-dependent, the technique offers security, as the signal can be purposely distorted in other positions. The composite dual-mode OAM signal makes it more difficult for eavesdroppers to demodulate correct messages. The receiver with a single antenna employs the phase compensation and helical phase factor to restore the correct digital signal in the desired position. Numerical results show that multitarget position-sensitivity OAM-DM technology based on FDA offers the security transmission scheme.

Cooperative Transmission Scheme Using the Single Antenna in the Broadcasting and Cellular System

2017 ◽  
Vol 95 (4) ◽  
pp. 4049-4061
Author(s):  
Hyun-Jee Yang ◽  
Bit-Na Kwon ◽  
Jung-In Baik ◽  
Hyoung-Kyu Song
Keyword(s):  
Cellular System ◽  
Cooperative Transmission ◽  
Transmission Scheme ◽  
Single Antenna

High Efficiency Dual-Mode Current Modulation Method for Low-Power DC/AC Inverters

2014 ◽  
Vol 29 (6) ◽  
pp. 2638-2642 ◽  
Author(s):  
Ahmadreza Amirahmadi ◽  
Lin Chen ◽  
Utsav Somani ◽  
Haibing Hu ◽  
Nasser Kutkut ◽  
...  
Keyword(s):  
Low Power ◽  
High Efficiency ◽  
Modulation Method ◽  
Dual Mode ◽  
Current Modulation

Dual mode modulation method for the full‐bridge converter operating in a wide input voltage range

2016 ◽  
Vol 52 (6) ◽  
pp. 470-471
Author(s):  
Lei Zhao ◽  
Haoyu Li ◽  
Shufeng Liu ◽  
Weihe Zeng
Keyword(s):  
Input Voltage ◽  
Modulation Method ◽  
Dual Mode ◽  
Voltage Range

scholarly journals Processing of Digital Signals in (+1, -1) Binary System

2021 ◽  
Vol 9 (VI) ◽  
pp. 4008-4026
Author(s):  
P. Chaubey
Keyword(s):  
Binary System ◽  
Vlsi Design ◽  
Digital Signal ◽  
Differential Pulse ◽  
Second Order ◽  
Modulation Method ◽  
Number Representation ◽  
Pulse Code Modulation ◽  
Differential Pulse Code Modulation ◽  
Code Modulation

Digital Signal Processing in (+1, -1) system has been studied in detail. Effects of number representation on quantization and truncation of rounding have been discussed. First order and second order filters have been investigated. Differential pulse code modulation method of coding is being studied. It is found that this system is well suited for VLSI design. The hardware realization of different components of DPCM is easy and straight. The position and negative signals can be processed in a unified way. It gives better performance in comparison of two’s complement representation of conventional binary system. The effect of limit cycles, stability and round off noise in first and second order filter have been discussed too.

New Dual-Mode FSE Suitable for High-Order QAM Signals

2013 ◽  
Vol 760-762 ◽  
pp. 478-482
Author(s):  
Hui Juan Gao ◽  
Yan Liu
Keyword(s):  
Steady State ◽  
Mean Square Error ◽  
Digital Transmission ◽  
High Order ◽  
Mean Square ◽  
Constant Modulus ◽  
Constant Modulus Algorithm ◽  
Dual Mode ◽  
Training Sequences ◽  
Second Mode

In the digital transmission system, constant modulus algorithm (CMA) is a famous blind equalization to overcome the inter-symbol interference without the aid of training sequences. But for the non-constant modulus signals such as higher-order QAM signals, the CMA just achieve moderate steady-state mean square error (MSE). So a new dual-mode fractionally-spaced equalization (FSE) suitable for high-order QAM signals is proposed, which makes full use of the character which is that the high-order QAM signals have the different modulus. This algorithm uses the FSE based on CMA as the basal mode and in the second mode it uses the FSE based on variable modulus algorithm. The simulation results show that compared with CMA the proposed algorithm has faster convergence rate and lower steady-state mean square error.

scholarly journals The use of Delfino digital signal controller in power inverter

2019 ◽  
Vol 28 ◽  
pp. 01017
Author(s):  
Krzysztof Górecki
Keyword(s):  
Control Algorithm ◽  
Single Phase ◽  
Digital Signal ◽  
Sampling Frequency ◽  
Modulation Method ◽  
Real Time Control ◽  
Time Control ◽  
Digital Signal Controller ◽  
Power Inverters ◽  
Made In

This article analyzes the implementation of control algorithm for a single-phase power inverter using digital signal controller (DSC). For this purpose, a floating-point digital signal controller with a trigonometric math unit was used. The controller’s task was to control the H-bridge through a dedicated driver for power MOSFET transistors. For this task, transistors made in NexFET technology with low channel resistance were used. The H-bridge is the main power device of a single-phase, two-level power inverter powered by a 12V battery. As a modulation method, regular modulation with carrier signal using a triangular signal was used. The main aim was to show the digital signal controller’s performance in real-time control of power inverters and to present the maximum sampling frequency of the inverter that can be obtained for the example having been analyzed.

Digital transmission of 12-lead electrocardiograms and duplex speech in the telephone bandwidth

1996 ◽  
Vol 2 (1) ◽  
pp. 42-49 ◽  
Author(s):  
J J Mckee ◽  
N E Evans ◽  
F J Owens
Keyword(s):  
Predictive Coding ◽  
Digital Signal ◽  
Digital Transmission ◽  
Full Duplex ◽  
Linear Predictive Coding ◽  
Compression Technique ◽  
Ecg Signals ◽  
Ecg Compression ◽  
Band Limited ◽  
Communications System

Summary A system was developed which allowed the simultaneous communication of digitized, full duplex speech and electrocardiography ECG signals in realtime. A single band-limited channel was used over a standard telephone line providing 3 kHz bandwidth. The full duplex speech was compressed to 2400 bit s using linear predictive coding, while multiple ECG signals were processed by a novel ECG compression technique. Extensive use of digital signal processing reduced the combined bit rate to less than 9600 bit s, allowing the use of lowcost commercial modems. The ECG communications system was tested in clinical trials. It enabled a hospitalbased clinician to provide diagnostic and treatment advice to a remote location over the standard telephone network.

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