M-ary Shift Keying Modulation Scheme Identification Algorithm Using Wavelet Transform and Higher Order Statistical Moment

2007 ◽  
Vol 8 (1) ◽  
pp. 112-119 ◽  
Author(s):  
P. Prakasam ◽  
M. Madheswara
Keyword(s):  
Wavelet Transform ◽  
Higher Order ◽  
Statistical Moment ◽  
Modulation Scheme ◽  
Identification Algorithm ◽  
Shift Keying

Analytical and experimental study on Van der Pol-type and Rayleigh-type equations for modeling nonlinear aeroelastic instabilities

2021 ◽  
pp. 136943322110220
Author(s):  
Guangzhong Gao ◽  
Ledong Zhu ◽  
Hua Bai ◽  
Wanshui Han ◽  
Feng Wang
Keyword(s):  
Aerodynamic Force ◽  
Early Stage ◽  
Higher Order ◽  
Empirical Modeling ◽  
Identification Algorithm ◽  
Van Der Pol ◽  
Single Degree Of Freedom ◽  
Section Shape ◽  
Vibration Responses ◽  
Aerodynamic Parameters

An empirical modeling of nonlinear aerodynamic force during aeroelastic instabilities, that is, vortex-induced vibration (VIV), galloping and flutter, is necessary in the estimation of vibration responses. Previous works on single-degree-of-freedom (SDOF) models suggest that nonlinear forms (Van der Pol or Rayleigh types) differ from section to section, which causes difficulty in practical application. Analytical evidences in this study have clarified that Van der Pol-type and Rayleigh-type models are equivalent in the amplitude-dependent aerodynamic damping; their difference lies in the higher-order harmonic responses. An identification algorithm of aerodynamic parameters is proposed to improve the robustness of aerodynamic parameters and guarantee the equivalence of both model types. Wind-tunnel tests of typical aeroelastic instabilities indicate that higher-order harmonic responses are small for VIV, galloping, and early-stage flutter instability when compared with the fundamental components due to weak nonlinearity. Van der Pol-type and Rayleigh-type models are both applicable until the flutter amplitude grows excessively large. It is clear that both model types are suitable for any section shape when use the proposed method of aerodynamic identification, and thus can be treated as a universal model for estimating the vibration amplitudes of nonlinear aeroelastic instabilities.

scholarly journals Analytical Models for the Computation of Error Probability of Multi-Level Phase Shift Keying Modulation Scheme

2021 ◽  
Vol 4 (1) ◽  
pp. 13-20
Author(s):  
Isaac A. E. ◽  
Dike H.U.
Keyword(s):  
Phase Shift ◽  
Error Probability ◽  
Error Function ◽  
Density Ratio ◽  
Analytical Models ◽  
Modulation Scheme ◽  
Noise Power ◽  
Phase Shift Keying ◽  
Shift Keying ◽  
Multi Level

In this paper, analytical models for the computation of error probability (BER) of the Multi-level Phase Shift Keying (MPSK) modulation scheme is presented. Analytical models for computing MPSK bit error probability based on Q function, error function (erf) and complementary error function (erfc) are presented. Also, an analytical model for computing the symbol error rate for MPSK is presented. Furthermore, a generalized analytical expression for BER as a function of modulation order (M) and energy per bit to noise power density ratio (Eb/No) is presented. The BER was computed for various values of M (2 ≤ M ≤ 256) and Eb/No (0 dB ≤ Eb/No ≤ 14 Db). The results showed that at Eb/No =12 dB, a BER of 9.006E-09 is realized for M =2 and M =4 whereas BER of 1.056E-01 is realized for M = 256. Also, for the same M = 2 , the value of BER decreased from 1.2501E-02 at Eb/No = 4 dB to 9.0060E-09at Eb/No =12 dB. Generally, the results showed that for the MPSK modulation scheme, for a given value of Eb/No, the lower modulation order (M) has a lower BER and for a given modulation order, (M) the BER decreases as Eb/No increases.

scholarly journals Experimental evaluation of spectral efficiency from a circular array antenna producing a Laguerre–Gauss mode

2020 ◽  
Vol 7 (12) ◽  
pp. 201711
Author(s):  
Ben Allen ◽  
Timothy D. Drysdale ◽  
Chris Stevens
Keyword(s):  
Phase Shift ◽  
Antenna Array ◽  
Spectral Efficiency ◽  
Field Measurements ◽  
Modulation Scheme ◽  
Phase Shift Keying ◽  
Additional Degree ◽  
Shift Keying ◽  
Mode Purity ◽  
Circular Antenna Array

We present the four-dimensional volumetric electromagnetic field measurements ( x , y , z and frequency) of the complex radiated field produced by an 8-element circular antenna array. The array is designed to produce a Laguerre–Gauss (LG) mode l = +1 over the frequency range of 9–10 GHz. We evaluate our findings in terms of far-field LG mode purity and spectral efficiency in terms of the quadrature amplitude modulation (QAM) modulation scheme that can be supported. The application of LG modes in radio systems is as a means of multiplexing several data streams onto the same frequency, polarization and time slot, thus making a highly spectrally efficient transmission system or enhancing radar systems by means of exploiting mode behaviour as an additional degree of freedom. Our results show that for the circular antenna array, we find that mode purity is sufficient to support binary phase shift keying or quadrature phase shift keying modulation over a 0.3 GHz bandwidth, which corresponds to a spectral efficiency of 1.5 b s −1 Hz −1 per mode. Closer to the antennas' design frequency, 256QAM modulation may be supported over a 0.05 GHz band, and which corresponds to a spectral efficiency of 11 b s −1 Hz −1 per mode. We anticipate the practical insights provided in this paper contribute to the successful design of such systems.

scholarly journals A reconfigurable software defined ultra-wideband impulse radio transceiver

2010 ◽  
Vol 8 ◽  
pp. 67-73 ◽  
Author(s):  
M. D. Blech ◽  
A. T. Ott ◽  
P. Neumeier ◽  
M. Möller ◽  
T. F. Eibert
Keyword(s):  
Software Defined Radio ◽  
Matched Filter ◽  
Digital Signal ◽  
Impulse Radio ◽  
Ultra Wideband ◽  
Modulation Scheme ◽  
Digital To Analog Converter ◽  
Shift Keying ◽  
Reconfigurable Software ◽  
Radio Transceiver

Abstract. An ultra-wideband (UWB) software defined radio (SDR) implementation is presented. The developed impulse radio (IR) transceiver employs first order bandpass (BP) sampling at a conversion frequency which is four times the channel bandwidth. The subsampling architecture directly provides the RF signal avoiding any non-ideal mixer stages and reduces the requirements of digital signal processing implemented in a field programmable gate array (FPGA). The transmitter consists basically of a multi-Nyquist digital to analog converter (DAC), whereas the implemented matched filter (MF) receiver prototype employs a standard digitizing oscilloscope. This design can be adaptively reconfigured in terms of modulation, data rate, and channel equalization. The reconfigurable design is used for an extensive performance analysis of the quadrature phase shift keying (QPSK) modulation scheme investigating the influence of different antennas, amplifiers, narrowband interferers as well as different equalizer lengths. Even for distances up to 7 m in a multipath environment robust communication was achieved.

DCSK performance analysis of a chaos-based communication using a newly designed chaotic system

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Namrata Biswas ◽  
Raja Mohamed I
Keyword(s):  
Chaotic System ◽  
Secure Communication ◽  
Chaotic Signal ◽  
Coherent Detection ◽  
Phase Portraits ◽  
Modulation Scheme ◽  
Threshold Control ◽  
New Chaotic System ◽  
Shift Keying ◽  
Chaos Shift Keying

Abstract In this paper, a new chaotic system has been introduced and the fundamental properties of the system were investigated and presented using a bifurcation diagram, max Lyapunov exponent (LE) and phase portraits. The synchronization of the drive and response system has been done using the threshold control parameter. Later the differential chaos shift keying (DCSK) modulation scheme has been carried out for the system as it is the most efficient modulation scheme. The demodulator detects the data without the use of chaotic signal phase recovery, as it uses the non-coherent detection technique. The results were compared with other modulation schemes using the bit error rate (BER) graph. It reveals that the proposed chaos-based system could be used for secure communication. The system has been implemented using the MATLAB Simulink technique.

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