Mobile communication has become an important part of our daily lives for voice communication, data sharing and access over the Internet. Mobile communication is an open network, so maintaining the privacy and reliability of data has always been anxiety. The reliability of the data against channel noise can be achieved by various error correction codes. The purpose of the channel coding process is to reduce the effect of some disruptive elements that the data is influenced in the transmission phase as much as possible. This procedure ensures that the data is delivered to the receiver with minimum error. In this study, a communication system was established in MATLAB environment for the transmission of five second audio signal. In this communication system, BER and MSE performances of four phase shift keying methods are obtained first. In the second phase of the study, the AWGN and Rician fading channels were individually coded with four different LBC types. Performance evaluation of these coding types was done with BER and MSE criteria. In the last part of the study, it was investigated which wavelet family is suitable for which level, in order to ensure audio transmission over AWGN and Rician fading channels with the least possible error. Four wavelet transform families at different levels were applied to the audio signal for LBC (7, 4), LBC (15, 8), LBC (17, 8) and LBC (23, 12) encoded channels, and the Mean Squared Error (MSE) performances were compared.

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The level of electromagnetic radiation (EMR) exposure increases day by day as natural consequences of technological developments. In recent years, the increasing use of cellular systems has made it necessary to measure and evaluate EMR originating from base stations. In this study, broadband and band selective electric field strength (E) measurements were taken at four different times in order to evaluate the change of short term E in Atakum district of Samsun, Turkey. The measurements were collected from 46 different locations using a SRM 3006 and a PMM 8053 EMR meter in a band from 100 kHz to 3 GHz, and the maximum E (Emax) and the average E (Eavg) were recorded. The highest values have been noticed in these measurements at 9.45 V/m and 17.53 V/m for Eavg and Emax respectively. Apart from these measurements, 24 hour long term E measurements were taken at a location where the highest value was observed and analyzed, to observe the change of Es during a day. At the end of the study, a tentative mathematical model that helps in computing the total E of the medium with 95% accuracy, was obtained.

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In many Wireless Sensor Network (WSN) applications, the location of the nodes in the network is required. A logical method to find Unknown Nodes (UNNs) in the network is to use one or several mobile anchors (MAs) equipped with GPS units moving between UNNs and periodically broadcast their current location. The main challenge at this stage is to design an optimum path to estimate the locations of UNNs as accurately as possible, reach all nodes in the network, and complete the localization process as quickly as possible. This article proposes a new path planning approach for MA-based localization called Nested Hexagon Curves (NHexCurves). The proposed model’s performance is compared with the performance of five existing static path planning models using Weighted Centroid Localization (WCL) and Accuracy Priority Trilateration (APT) localization techniques in the obstacle-presence scenario. With the obstacle-handling trajectories used for the models, the negative impact of the obstacle on the localization is reduced. The proposed model provides full coverage and high localization accuracy in the obstacle-presence scenario. The simulation results show the advantages of the proposed path planning model with the H-curve model over existing schemes.

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Mobile communication has become an important part of our daily lives for voice communication, data sharing and access over the Internet. Mobile communication is an open network, so maintaining the privacy and reliability of data has always been anxiety. The reliability of the data against channel noise can be achieved by various error correction codes. The primary purpose of the channel coding process is to reduce the effect of disturbing influences to the minimum level. In this way, the receiver will be able to receive the data sent by the transmitter with the minimum error. In this research paper, it is required to acquire two audio signals with 8 bits of resolution and 8 kHz sampling frequency for 5 seconds in MATLAB. In the first part of this study, Reed-Solomon (RS) Coding Method was used to transmit two audio data recorded in .wav format with minimum error. Binary Phase Shift Keying (BPSK) modulation was used as the modulation method. The Bit Error Rate (BER) performance curve was plotted and the difference between the original and the received signal was observed. According to the BER performance curve, as the signal to noise ratio increases, less false data is received at the receiver. In the second part of the study, four wavelet transform families at different levels were applied to the audio signal, and the performances of these classes were compared.

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