Electrocardiogram (EKG or ECG) is an important electrical activity of the human Heart. ECG is used for the primary diagnosis of heart diseases since it shows the electrophysiology of the heart and the ischemic changes that may occur like the myocardial infarction, conduction defects, and arrhythmia. But, in real condition, ECG is often corrupted by different artifacts and noises. For the purpose of quality diagnosis, the ECG signal must be clearly de-noised to remove all noises and artifacts from the signal. In this paper, we present the Wavelet Transform, a new approach in digital signal processing to filter the ECG signal. Different ECG signals from M IT/BIH arrhythmia database are used with added 10dB, 5dB & 0dB Power Line Interference (PLI) noise which is common in ECG signal. The results were evaluated using M ATLAB software. Basically, two synthesis parameters M ean Square Error (M SE) and Signal to Noise ratio (SNR) have been used. The prime aim of this paper is to adapt the discrete wavelet transform (DWT) to improve the (ECG) signal quality for better clinical diagnosis. The evaluated results have been compared with Butterworth IIR filter. The proposed method shows improvement in output SNRo for 5dB noise is 98.5% and for 10dB noise is 95.7%.

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Summary IEEE 802.11n is a high‐speed wireless broadband local area networking standard. IEEE 802.11n‐based devices are using some kind of adaptive modulation‐coding (AMC) scheme to adjust its transmission rate according to the radio channel condition. In these devices, however, the concept of guard interval adaptation is not been considered. Normally, orthogonal frequency division multiplexing (OFDM) technology‐based systems are using the guard interval much greater than the length of the channel impulse response. However, many previous works have shown that the choice of the larger guard interval is inefficient in terms of achievable throughput. IEEE802.11n supports using two guard intervals (short = 400 ns or long = 800 ns). Indeed, the shorter guard interval evidently results in intersymbol interference (ISI) and intercarrier interference (ICI), but the gain offered by shortened guard interval may exceed the loss caused by interference. In this paper, we propose a novel but simple solution for the guard interval adaptation joint with an adaptive modulation‐coding scheme to optimize the throughput performance of a wireless local area network (WLAN) system. This paper aims to analyze the effect of joint adaptive modulation‐coding and the guard interval (JAMCGI) algorithm on the WLAN system under bit‐error‐rate (BER) constraints. Simulation results and their analysis show a significant increase in the throughput performance of the WLAN system with our proposed algorithm.

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