Performance evaluation and implementation of convolution coded OFDM modem in wireless underwater acoustic communication

Abstract

High-data transmission rate and reliable communication in underwater acoustic channel is challenging because of limited bandwidth, multipath propagation, and Doppler shift, which results in poor bit error performance. Under this constraint, this paper explains the simulation results of underwater wireless acoustic data transmission system by using quadrature phase shift keying modulation with convolution encoder at the transmitter and proposed Viterbi decoder at the receiver. The decoder algorithm in comparison with MATLAB inbuilt function shows asserting improved results. This paper evaluates the performance of convolution coded orthogonal frequency division multiplexing modem, which is studied over typical underwater channel through an extensive computer simulation and a semirealistic experimentation. The performance of convolution coded orthogonal frequency division multiplexing system is measured in time domain plots, bit error rate curves, and number of bit errors per frame over additive white Gaussian noise and Rayleigh channel conditions. KEYWORDS convolution coded orthogonal frequency division multiplexing (CCOFDM), convolution encoding, QPSK (quadrature phase shift keying), underwater wireless acoustic modem, Viterbi decoding

Identification and processing of in-ear acoustic signals

“…In digital transmission systems, convolution encoding is a very efficient way to encode [7]. Convolution can be understood from the perspective of input signal: how each sampling point of the input signal is contributed to multiple output signal sampling points, that is, after each input signal component enters the linear system, multiple translation and scaling versions of the pulse reaction will be generated, and the output result is the synthesis of the translation and scaling version of the pulse reaction corresponding to each signal component; Understand from the perspective of the output signal: how the sampling point of each output signal obtains information from the many input signal sampling points.…”

Underwater acoustic sensor networks: Taxonomy on applications, architectures, localization methods, deployment techniques, routing techniques, and threats: A systematic review

“…Challa and Mosa 30 presented a single‐carrier QPSK modem and subsequently demonstrated that the suggested decoder method outperforms the competition in terms of BER performance. Multicarrier CCOFDM over multiple channels improves BER performance even further.…”

An improved underwater wireless sensor network communication using Internet of Things and signal to noise ratio analysis

“…Another difficult aspect of UWSNs is node mobility. UWSNs are made up of tiny devices called nodes that move around owing to water currents 13 . These fluctuations have been documented as roughly 1 to 3 m/s, which is enough to cause the network to become unstable.…”

“…UWSNs are made up of tiny devices called nodes that move around owing to water currents. 13 These fluctuations have been documented as roughly 1 to 3 m/s, which is enough to cause the network to become unstable. Because of these constraints, typical WSN routing techniques cannot be used for UWSNs.…”