Binary Amplitude Shift Keying Research Articles

Digital Modulator using Digitally Programmable Complementary metal–oxide–semiconductor Differential Voltage Current Conveyor

This study aims to Developing a digital modulation system using a new technology and idea, which is the digitally programmable CMOS (Complementary metal–oxide–semiconductor), Integrate the CMOS DVCC circuit as a modulator in the communication systems, as will be explained in chapter 3, Finally, simulate this new idea in communication by using a simulation program, which is PSpice software, and analyzing the results. By focusing on How to use digital programmable CMOS (Complementary Metal–Oxide–Semiconductor) in a communication system as a digital modulator, Verifying the effectiveness of the study using simulation software such as PSpice and MATLAB, and Analyzing and verifying the effectiveness of the three modified modulation techniques. Digitally programmable Binary Amplitude shift keying (DP BASK), Digitally programmable Binary Phase shift keying (DP BPSK), And Digitally programmable Binary Frequency shift keying (DP BFSK). This study adopts an applied research approach. The study demonstrated that the CMOS DVCC circuit could be successfully integrated into communication systems as a digital modulator. The study recommended to conduct further research on the noise resistance capabilities of the DP modulation techniques, and explore additional modulation techniques that could benefit from digitally programmable CMOS technology, such as Quadrature Amplitude Modulation (QAM) or Orthogonal Frequency-Division Multiplexing (OFDM).

FPGA Implementation of Digital Modulation Schemes Using Verilog HDL

Abstract: This paper describes the design and development of an FPGA-based digital Modulation Scheme for high-resolution Communication Application. We are focusing on implementation of Verilog based code simulation for fundamental and widely used digital modulation techniques such as Binary Amplitude-shift keying (BASK), Binary Frequency-shift keying (BFSK), Binary Phase-shift keying (BPSK) and Quadrature Phase Shift Keying(QPSK). In this work the idea of sinusoidal signals that have been generated is plain sailing in nature and based on fundamentals of signal sampling and quantization. Such concept of sinusoidal signals generation is not unfamiliar but somehow simplified using sampling and quantization in time and amplitude domain, respectively. The whole simulation is done on Modelsim and Xilinx-ISE using VERILOG Hardware descriptive language. The work has been accomplished on Thirty two bit serial data transmission with self-adjustable carrier frequency and bit duration length.

Radiation Principle and Spatial Direct Modulation Method of a Low Frequency Antenna Based on Rotating Permanent Magnet

The theory of mechanical antenna is still in its infancy at present, and its radiation mechanism, field distribution, modulation methods and other basic theories need to be explored and improved. The radiation mechanism of a rotating-magnet based mechanical antenna (RMBMA) is explored. An equivalent radiation model of the mechanical antenna is established. The field formula of mechanical antenna is derived using this model and rotation matrix. The spatial direct modulation method of mechanical antenna is also investigated. Two prototype antennas are fabricated using DC/AC servo motors and NdFeB magnets, and experiments are carried out to verify the correctness of the derivation and analysis. The measured and simulated results are in consistent with each other. By precisely controlling the moving parameters of an AC servo motor, signal of binary amplitude shift keying (BASK) is generated, and the original code sequence is recovered by demodulation.

BER-Aware Backscattering Design for Energy Maximization at RFID Passive Tag

AbsThe radio frequency identification (RFID) passive tag is wireless communication device with high energy sustainability, such that it uses the incident radio frequency (RF) signal to backscatter its information. This paper investigates the output load power maximization with optimal load impedances selection in the backscatter communication (BackCom) network. The considered BackCom system comprises a reader broadcasting an unmodulated carrier to the passive tag in the downlink. The tag backscatters its information signal to the reader with binary amplitude-shift keying (BASK) modulation in the uplink. We formulated an average output load power maximization problem by jointly optimizing the reflection coefficients while satisfying the minimum bit error rate (BER) requirement and tag sensitivity constraint. To simplify the problem, we transform the BER constraint to the modulation index constraint and reduce the 4 variables problem to 2 variables convex optimization problem. Using the Karush-Kuhn-Tucker (KKT) conditions, we design an algorithm to obtain the closed-form expression for the global optimal reflection coefficients that maximize the output load power. The simulation results provide insight into the impact of the information bit probability, tag sensitivity constraint, and BER on the achievable average load power. An overall gain of around 16% signifies the utility of our proposed design.

Single Dual-X Current Conveyor based BASK/BPSK Modulators

Two voltage mode digital modulators have been proposed i.e. Binary Amplitude Shift Keying (BASK) modulator and Binary Phase Shift Keying (BPSK) modulator. Both circuits use Dual-X Second Generation Current Conveyor (DXCCII) as the active building block and have the advantages of proper input impedances and use of grounded resistor. Detailed mathematical analysis of both circuits are given. The circuits have been simulated with SPICE using 0.35µm CMOS technology parameters. The supply voltage of ±1.8 V is used. Much satisfactory results have been obtained with the proposed circuits.

A Computational Piezoelectric Micro-Machined Ultrasonic Transducer Toward Acoustic Communication

Piezoelectric micro-machined ultrasonic transducers (pMUTs) are gaining popularity in integrated smart ultrasonic systems. In this letter, we report a pMUT toward acoustic communication with mechanical computation ability for the first time. The novel pMUT design can successfully operate 2-bit OR, XOR, XNOR, and NOT mechanical logic operations based on resonance frequency tuning. The proposed mechanical actuation can operate steady and reliable binary amplitude shift keying (BASK), binary frequency shift keying (BFSK) modulations with its naturally detached resonance modes in a single device. Such an idea can greatly reduce the complexity and cost of the acoustic communication system design in terms of hardware. A minimum response time of about 0.14 ms is achieved with the proposed device, equivalent to a bit rate over 3.5 kb/s. In addition, a higher data rate can be achieved since the operating speed can be greatly improved by impedance matching and shrinking the pMUT size.

Data Exfiltration from Air-Gapped Computers based on ARM CPU

Air-gapped Network is a network isolated from public networks. Several techniques of data exfiltration from air-gapped networks have been recently proposed. Air-gap malware is a malware that breaks the isolation of an air-gapped computer using air-gap covert channels, which extract information from air-gapped computers running on air-gap networks. Guri et al. presented an air-gap malware “GSMem”, which can exfiltrate data from air-gapped computers over GSM frequencies, 850 MHz to 900MHz. GSMem makes it possible to send data using the radio waves leaked out from the system bus between CPU and RAM. It generates binary amplitude shift keying (B-ASK) modulated waves with x86 SIMD instruction. In order to efficiently emit electromagnetic waves from the system-bus, it is necessary to access the RAM without being affected by the CPU caches. GSMem adopts an instruction that writes data without accessing CPU cache in Intel CPU. This paper proposes an air-gap covert channel for computers based on ARM CPU, which includes a software algorithm that can effectively cause cache misses. It is also a technique to use NEON instructions and transmit B-ASK modulated data by radio waves radiated from ARM based computer (e.g. Raspberry Pi 3). The experiment shows that the proposed program sends binary data using radio waves (about 1000kHz ~ 1700kHz) leaked out from system-bus between ARM CPU and RAM. The program can also run on Android machines based on ARM CPU (e.g. ASUS Zenpad 3S 10 and OnePlus 3).

Improvement of Measurement Range via Chaotic Binary Frequency Shift Keying Excitation Sequences for Multichannel Ultrasonic Ranging System

The important indicators of multichannel ultrasonic ranging system are correlation characteristics and energy efficiency. The excitation sequences with good correlation characteristics can help avoid crosstalk among multichannel ultrasonic sensors. High energy efficiency can enhance measurement range. This paper proposes a crosstalk elimination method by using the optimal binary excitation sequences modulated with chaotic codes, which include chaotic binary amplitude shift keying (c-BASK), chaotic binary phase shift keying (c-BPSK) and chaotic binary frequency shift keying (c-BFSK). To obtain the both best correlation characteristics and energy efficiency, the Nondominated Sorting Genetic Algorithm-II (NSGA-II) is applied to optimize the chaotic binary excitation sequences. Real experiments have been conducted using an ultrasonic ranging system that consists of eight-channel SensComp 600 series instrument-grade electrostatic sensors excited with chaotic binary modulation sequences. The experimental results show that the c-BFSK outperforms the c-BASK and c-BPSK in terms of the correlation characteristics and energy efficiency. With 2 ms c-BFSK excitation sequences, the longest measurable distance was 720 cm (i.e., increased 11% and 27% with c-BPSK and c-BASK, respectively) with maximal relative error 2.4%.

Effect of the acoustic impedance in ultrasonic emitter transducers using digital modulations

The existing technologies using electromagnetic waves or lasers are not very efficient due to the large attenuation in the aquatic environment. Ultrasound reveals a lower attenuation, and thus has been used in underwater long-distance communications. For high data-rates and real-time applications it is necessary to use frequencies in the MHz range, allowing communication distances of hundreds of meters with a delay of milliseconds. To achieve this goal, it is necessary to develop ultrasound transducers able to work at high frequencies and wideband, with suitable responses to digital modulations. This work shows how the acoustic impedance influences the performance of an ultrasonic emitter transducer when digital modulations are used and operating at frequencies between 100kHz and 1MHz. The study includes a Finite Element Method and a MATLAB/Simulink simulation with an experimental validation to evaluate two types of piezoelectric materials: one based on ceramics (high acoustic impedance) with a resonance design and the other based in polymer (low acoustic impedance) designed to optimize the performance when digital modulations are used. The transducers performance for Binary Amplitude Shift Keying, On–Off Keying, Binary Phase Shift Keying and Binary Frequency Shift Keying modulations with a 1MHz carrier at 125kbps baud rate are compared.

Chaotic Binary Modulation Excitation Sequences for Multichannel Ultrasonic Ranging System

A crosstalk elimination method by using the optimal binary excitation sequences modulated with chaotic codes, which includes chaotic binary amplitude shift keying (c-BASK), chaotic binary phase shift keying (c-BPSK) and chaotic binary frequency shift keying (c-BFSK), is proposed in this paper. The selection of the optimal chaotic initial values with the best echo correlation characteristics is realized by adopting a genetic algorithm. A square wave is used as the carrier of the chaotic binary modulation methods in order to reduce hardware cost. However, it could suffer from the decreased energy efficiency caused by mismatching spectrum with ultrasonic ranging system. The parameters of the chaotic binary modulation methods are configured to make their central frequency and bandwidth matched with that of the ultrasonic ranging system very well. Experiments have been conducted using an ultrasonic ranging system that consists of eight-channel SensComp 600 series instrument-grade electrostatic sensors excited with chaotic binary sequences. Experimental results show that the c-BFSK outperforms the c-BASK and c-BPSK in terms of the energy efficiency, e.g., 0.3508 vs. 0.3365 and 0.3279 , respectively. And the optimized c-BFSK sequence also has the best echo correlation characteristics among the chaotic binary modulation sequences. http://dx.doi.org/10.11591/telkomnika.v12i12.4640

Analysis and Design of Network-Based Control Systems with Binary Modulation

Network-based control systems have been emerging technologies in control and computer communication fields over the past decade. This paper focuses on the analysis and design of network-based control systems with binary modulation. First, it is shown that different modulations can result in different delays which are inevitable in network-based control systems. The delay can be seen as constant delay when the transmission time is the main consideration. Second, channel noise can result in bit error while bit error is seen as active packet loss in this paper, in this context, the conditions of signal-to-noise ratio (SNR) for binary modulation that can guarantee the stability of systems are obtained according to the proposed algorithm. Third, the system with delay and noisy communication can be modeled as an asynchronous dynamic system (ADS); in addition, the stability is analyzed and controller is designed in terms of Lyapunov function and linear matrix inequality (LMI) scheme. Finally, without loss of generality, numerical simulation demonstrates the effectiveness of the proposed scheme and designed controller based on binary amplitude shift keying (2ASK) modulation.

Properties, performance and practical interest of the widely linear MMSE beamformer for nonrectilinear signals

Widely Linear (WL) Minimum Mean Square Error (MMSE) estimation has received a great interest these last 20 years for second order (SO) noncircular signals. In the context of radio communications networks, it has been shown in particular that WL MMSE receivers allow to implement Single Antenna Interference Cancellation (SAIC) of one rectilinear interference, such as Binary Phase Shift Keying (BPSK) or Amplitude Shift Keying (ASK) interference, or of quasi-rectilinear interference, such as Minimum Shift keying (MSK), Gaussian MSK (GMSK) or Offset Quadrature Amplitude Modulation (OQAM) interference, hence their great interest for Global System for Mobile Communications (GSM) cellular networks in particular. However, one may wonder whether WL MMSE receivers remain attractive for SO noncircular nonrectilinear interferences, not so scarce in practice. The purpose of this paper is mainly to answer to this important question by giving, in a self-contained and unified way, some new insights into the behavior, properties and performance of the WL MMSE beamformer in the presence of arbitrary noncircular signals and interference which are not necessarily rectilinear. It is shown in particular that, surprisingly, WL MMSE receivers lose their practical interest for strong interferences which are not rectilinear. This breakthrough thus generates a new open problem for the choice between linear and WL MMSE receiver corresponding to the detection of rectilinearity (and/or quasi-rectilinearity), instead of noncircularity, in a given noisy observation. Although this question is out of the scope of this paper, we finally propose preliminary tools based on blind source separation methods to solve this problem.

Electromagnetic wave propagation of wireless capsule endoscopy in human body

Wireless capsule endoscopy (WCE) is a promising technique which has overcome some limitations of traditional diagnosing tools, such as the comfortlessness of the cables and the inability of examining small intestine section. However, this technique is still far from mature and asks for the feasible improvements. For example, the relatively low transmission data rate and the absence of the real-time localization information of the capsule are all important issues. The studies of them rely on the understanding of the electromagnetic wave propagation in human body. Investigation of performance of WCE communication system was carried out by studying electromagnetic (EM) wave propagation of the wireless capsule endoscopy transmission channel. Starting with a pair of antennas working in a human body mimic environment, the signal transmissions and attenuations were examined. The relationship between the signal attenuation and the capsule (transmitter) position, and direction was also evaluated. These results provide important information for real-time localization of the capsule. Moreover, the pair of antennas and the human body were treated as a transmission channel, on which the binary amplitude shift keying (BASK) modulation scheme was used. The relationship between the modulation scheme, data rate and bit error rate was also determined in the case of BASK. With the obtained studies, it make possible to provide valuable information for further studies on the selection of the modulation scheme and the real-time localization of the capsules.

Binary amplitude shift keying based signal processing for brillouin optical correlation domain analysis

We propose and experimentally demonstrate a novel binary amplitude shift keying (BASK) based signal processing for Brillouin optical correlation domain analysis with better noise performance. To subtract the background noise substructure from the conventional, broadened Brillouin signal, this method utilizes the presence of two sidebands, leading to a fourfold improvement of the spatial resolution compared to that of an ordinary BOCDA system with the same modulation parameters.

FPGA Implementation of BASK-BFSK-BPSK Digital Modulators [Testing Ourselves

Field-programmable gate-array (FPGA) implementations of binary amplitude-shift keying (BASK), binary frequency-shift keying (BFSK), and binary phase-shift keying (BPSK) digital modulators are presented. The proposed designs are aimed at educational purposes in a digital communication course. They employ the minimum number of blocks necessary for achieving BASK, BFSK, and BPSK modulation, and for full integration with the other functional parts of the Altera Development and Education (DE2) FPGA board. The input carrier signal and the bit stream (modulating signal) are user controllable. These digital modulators were developed and compiled to a Verilog Hardware Description Language (HDL) netlist, and were later implemented into an Altera DE2 FPGA board. The functionality of these digital modulators was demonstrated through simulations using the Quartus II simulation software, and experimental measurements of the real-time modulated signal via an oscilloscope.

Quadrature Amplitude Modulated Backscatter in Passive and Semipassive UHF RFID Systems

Passive and semipassive UHF RF identification (RFID) systems have traditionally been designed using scalar-valued differential radar cross section (DRCS) methods to model the backscattered signal from the tag. This paper argues that scalar-valued DRCS analysis is unnecessarily limiting because of the inherent coherence of the backscatter link and the complex-valued nature of load-dependent antenna-mode scattering from an RFID tag. Considering modulated backscatter in terms of complex-valued scattered fields opens the possibility of quadrature modulation of the backscatter channel. When compared with binary amplitude shift keying (ASK) or phase shift keying (PSK) based RFID systems, which transmit 1 bit of data per symbol period, and thus 1 bit per on-chip clock oscillator period, tags employing vector backscatter modulation can transmit more than 1 bit per symbol period. This increases the data rate for a given on-chip symbol clock rate leading to reduced on-chip power consumption and extended read range. Alternatively, tags employing an M-ary modulator can achieve log2 M higher data throughput at essentially the same dc power consumption as a tag employing binary ASK or PSK. In contrast to the binary ASK or PSK backscatter modulation employed by passive and semipassive UHF RFID tags, such as tags compliant with the widely used ISO18000-6c standard, this paper explores a novel CMOS-compatible method for generating M-ary quadrature amplitude modulated (QAM) backscatter modulation. A new method is presented for designing an inductorless M-ary QAM backscatter modulator using only an array of switched resistances and capacitances. Device-level simulation and measurements of a four-state phase shift keying (4-PSK)/four-state quadrature amplitude modulated (4-QAM) modulator are provided for a semipassive (battery-assisted) tag operating in the 850-950-MHz band. This first prototype modulator transmits 4-PSK/4-QAM at a symbol rate of 200 kHz and a bit rate of 400 kb/s at a static power dissipation of only 115 nW.

Transceiver Design for MIMO Systems with Improper Modulations

This paper considers joint transceiver designs for single-user multiple-input, multiple-output systems employing improper constellations such as binary phase shift-keying and M-ary amplitude shift-keying (M-ASK). Proposed are novel joint linear transceivers that minimize the total mean squared error of the symbol estimation at the output of the decoder. The joint linear transceiver designs are carried out for both cases of perfect channel state information (CSI) and imperfect CSI at the transmitter and receiver. For the case of imperfect CSI, the channel model takes into account both transmit and receive correlations as well as the channel estimation error. The superiority of the proposed transceivers over the previously-proposed designs is verified by simulation results.

Optimized Pseudorandom BASK Emission Sequences for Ultrasonic Multi-Life Location System

This paper addresses the performance of pseudorandom Binary Amplitude Shift Keying (BASK) emission sequences for an ultrasonic multi-life location system in rescue robot. To improve the performance of multi-life location system, the BASK modulation were used to construct the spread spectrum emission sequences for ultrasonic sensors. Correlation technique in the receiving circuit was used to de-spread. Good correlation characteristics, i.e., sharp autocorrelation and flat cross-correlation, can help eliminate crosstalk between multichannel ultrasonic sensors. To improve the echo signal correlation effect, genetic algorithm was applied to optimize pseudorandom m sequences. In simulated post-earthquake environment, experimental verification of ultrasonic multi-life location system consisting of eight-channel SensComp 600 series electrostatic sensors with optimized BASK emission sequences was carried out. The experimental results demonstrate that the ultrasonic multi-life location system with the proposed method can realize multi-life location simultaneously.

Wireless Environmental Monitoring Device

This wireless environmental monitoring device is based on the principle of binary Amplitude Shift Keying (2ASK). Under the control of ultra-low-power single-chip microcomputer MSP430F449, the device can detect the temperature an light around it. The detect system consists of monitoring terminal, detecting nodes and coupling coils. In the mode of UART asynchronous communication, the device can realize the function of wireless data transmission with the carrier of 8MHz. Monitoring terminal and detecting nodes are both applied on the same transceiver circuit. The transmitter achieves 2ASK modulation by using the keying method. The receiver achieves 2ASK demodulation by using the envelope detection method. Detection nodes are battery powered.It can preset code, detecting the ambient temperature and light, and then transmit the message automatically. The absolute error of measured temperature is below 2°C, and the absolute error of power consumption is below 0.2W. Monitoring terminal uses one single power supply. It can communication with the detecting nodes directly, and display the node number and the detected information. In the condition of detecting delay is below 2S and detecting range D + D is above 50cm, the supply power of the monitoring terminal ≤ 0.5W. The whole system has simple circuit, low power consumption and multifunction.

Coherent optical binary polarisation shift keying heterodyne system in the free-space optical turbulence channel

In this study, analytical and simulation results for the bit error rate (BER) performance and fading penalty of a coherent optical binary polarisation shift keying (2PolSK) heterodyne system adopted for a free-space optical communication link modelled as the log-normal and the negative exponential atmospheric turbulence channels are presented. The conditional and unconditional BER expressions are derived, demonstrating the comprehensive similarity between the 2PolSK and the binary frequency shift keying schemes with regard to the system sensitivity. The power penalty owing to the non-ideal polarisation beam splitter is also analysed. The receiver sensitivity employing 2PolSK is compared with other modulation schemes in the presence of turbulence and the phase noise. The results show that 2PolSK offers improved signal-to-noise ratio performance compared to the binary amplitude shift keying.