• Chandrakant Tiwari

The Modeling and Simulation can play a most- vital role during all phases of the design and engineering of communication systems. Orthogonal Frequency Division Multiplexing (OFDM) is predicted to be implemented in future broadcasting and systems due to its robustness in transmitting a high data rate was originally developed from the multicarrier modulation techniques used in high frequency military radios. It is modulated data streams are divided into number of parallel sub-streams which occupies a very less bandwidth. However, full justice was done in proper utilization of bandwidth in OFDM where subcarriers overlap orthogonally. A multiple-input multiple-output (MIMO) communication System combined with the orthogonal frequency division multiplexing (OFDM) modulation technique can achieve reliable high data rate transmission over broadband wireless channels. The QAM is one of the adaptive modulation techniques that are commonly used for wireless communications. Different order modulations allow sending more bit per symbol and thus achieving higher throughput or better SNR are needed to overcome any interference and maintain a certain BER. This paper at developing a simulink model to simulate different types of QAM modulation and demodulation techniques at different bit rates In this paper, simulation system is implemented using different channel like Additive White Gaussian Noise channel (AWGN) and fading channel with QAM modulation scheme and the performance analysis of Bit Error rate (BER) verses Signal to Noise ratio (SNR). The performance of MIMO-OFDM is tested for modulation techniques namely QAM using MATLAB-2013.

MODULATION, OFDM, MIMO, AWGN, BPSK, QAM, BER, SNR, etc

"Similitude Explication of MIMO- OFDM by using Various Fading Channels with QAM Modulation Scheme", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 3, page no.147-150, March-2019, Available :http://www.jetir.org/papers/JETIRAI06023.pdf

"Similitude Explication of MIMO- OFDM by using Various Fading Channels with QAM Modulation Scheme", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 3, page no. pp147-150, March-2019, Available at : http://www.jetir.org/papers/JETIRAI06023.pdf