Two Efficient Algorithms for Increasing OFDM Performance with Highly Complicated Fading Channel

Subject Areas : Communication

Saeed Ghazi-Maghrebi ¹ , Mohammad Hosein Tavassoli ² , Mohammad Ghazi-Maghrebi ³ , Reza Nematollahi ⁴

1 - Communications Department, Yadegar Imam Khomeini (RAH) Shahr-e-Rey Branch, Islamic Azad University, Tehran, Iran
2 - Communications Department, Yadegar Imam Khomeini (RAH) Shahr-e-Rey Branch, Islamic Azad University, Tehran, Iran
3 - Communications Department, Yadegar Imam Khomeini (RAH) Shahr-e-Rey Branch, Islamic Azad University, Tehran, Iran
4 - Communications Department, Yadegar Imam Khomeini (RAH) Shahr-e-Rey Branch, Islamic Azad University, Tehran, Iran

Received: 2019-02-10 Accepted : 2019-05-28 Published : 2019-09-01

Keywords: Genetic Algorithm, OFDM, Adaptive equalizer, S-MMA,

Abstract :

Equalization is a kind of the preferred methods for increasing the efficiency of modern digital communication systems. The paper contribution lies in using a modified version of Sliced Mul-ti-Modulus Algorithm (S-MMA) and genetic algorithm (GA) for updating per-tone equaliza-tions taps in the OFDM modulation using too long complicated fading channel, present of dif-ferent noises and ISI impairment. For more efficiency, it is assumed that the channel impulse response is longer than the cyclic prefix length and as a result, the system will be more efficient but at the expense of the high ISI impairment. Both mathematical analysis and computer simu-lations demonstrate the better performance of the new proposed application of the S-MMA and GA are compared to commonly used equalizer methods such as the LMS, RLS and multi modu-lus algorithm (MMA) in the channels with AWGN, burst noises and ISI impairment simultane-ously. Therefore, the new modified S-MMA equalization and GA are good candidates for high speed and real-time applications such as DAB, WiFi, WiMAX, and DVB systems.