Open AccessChannel estimation for image restoration using OFDM with various digital modulation schemes
Author(s) -
Varshini Rajesh,
A. R. Abdul Rajak
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1706/1/012076
Subject(s) - orthogonal frequency division multiplexing , additive white gaussian noise , phase shift keying , computer science , bit error rate , modulation (music) , channel (broadcasting) , electronic engineering , multipath propagation , channel state information , fading , algorithm , wireless , telecommunications , engineering , physics , acoustics
Channel or spectral estimation is a ground-breaking feature in wireless communication systems as it helps in obtaining information about a wireless channel at any state of time. Employing this can help in reducing the intensity of noise and bit error rate (BER). Here, images are processed, channels are estimated and image restoration is being done. Orthogonal Frequency Division Multiplexing (OFDM) is looked upon as a very popular multiplexing cum modulation technique used in wireless communication systems and so, it is selected to play a cardinal role in channel estimation. The LMS algorithm is preferred in this technique since it is a simpler technique and provides results which are desirable. To simulate realistic conditions, OFDM signal is passed through Additive White Gaussian Noise (AWGN) and also a multipath fading channel. In this paper, an FFT based OFDM, adopting several digital modulation techniques like BPSK, QPSK, 8PSK and 16QAM is being implemented on images. The values of BER is observed for different values of SNR and a comparison is drawn out for the aforementioned modulation techniques. Results prove that BPSK provides the least BER for a particular value of SNR and hence, it can be observed to give the best performance.