Acoustic vortices with subwavelength dimensions and tunable topological charge are theoretically experimentally synthesized at distances far beyond the Rayleigh diffraction length of source, using self-demodulation. A dual helical acoustic source is used to generate two primary confocal vortex beams different frequencies charges. As a consequence conservation angular momentum during nonlinear w...

Fiber optic Fabry–Pérot sensors have been widely developed with unique advantages, such as ease of reuse, resistance to electromagnetic interference, light weight, and their ability work in extreme environments. There are many demodulation methods that can be applied fiber sensors, including the intensity method, spectral demodulation, phase carrier but these cannot meet requirements take into ...

This paper deals with an improved demodulation technique for LoRa signal. The principle consists of detecting the possible errors demodulation, by comparing highest peak periodogram dechirped received signal weighted a coefficient β other peaks periodogram. If error is detected, second stage processed at oversampling rate (OSR) higher than first stage. Otherwise, result kept. A thorough perform...

Multi-point vibration sensing at the low frequency range of 0.5-100 Hz is of vital importance for applications such as seismic monitoring and underwater acoustic imaging. Location-resolved multi-point sensing using a single fiber and a single demodulation system can greatly reduce system deployment and maintenance costs. We propose and demonstrate the demodulation of a fiber-optic system consis...

In burst communication systems like Body Area Networks (BAN), burst packet should be detected prior to the demodulation of the signal at the receiver. Meanwhile, different modulation and demodulation algorithms may affect the BER performance of the entire system seriously. To satisfy the conditions that BAN nodes or devices have to be small in size and very low in power consumption, algorithm d...

Gear transmission system is as an important part of the vehicle, and its work reliability directly affects the working performance of vehicle. A JZQ-250 gear transmission system is as the object, and the gear’s and bearing’s characteristic frequencies of gearbox are got by analyzing the test platform, structure parameters, operating principle, and the layout of measuring point. The vibration si...

Bit interleaved coded modulation (BICM) schemes have been shown to increase the diversity order. This paper studies the extension of such schemes with iterative demodulation and decoding (ID) using error correcting codes coupled with rotated MPSK signal constellations with different symbol mappings and signal space diversity (SSD). Using extrinsic information transfer (EXIT) charts, an analysis...

This paper presents the implementation of Bluetooth Low Energy Controller (BTLE), Low Intermediate Frequency (IF), Gaussian Frequency Shift Keying (GFSK) Modulation and Demodulation technique. The GFSK modulation uses a bandwidth bit period product BT=0.5. The modulation index shall be configurable between 0.45 and 0.55. A binary one shall be represented by a positive frequency deviation, and a...

Abstract— Now-a-days Radar Signal Processing system is gaining a great deal of attention for realization of on-chip programmable signal processor for its real time applications. Application specific systems are being implemented using wide spectrum of Digital Signal Processing (DSP) algorithms. Such is the case for COordinate Rotation DIgital Computer (CORDIC) algorithm which is turned out to b...

Decoding high complexity is a major issue to design decode and forward (DF) relay protocol. Thus, the establishment of low decoding system would beneficial assist This paper reviews existing methods for min-sum based LDPC as system. Reference lists chosen articles were further reviewed associated publications. introduces comprehensive model representing describing developed DF It consists numbe...