Modulasi digital mendapat populariti dan perhatian besar-besaran dari setiap sudut dunia hari ini. Antara teknik modulasi digital, QAM digunakan secara meluas dan aplikasinya membantu mempercepat komunikasi data, misalnya pertukaran data dan pemindahan. BER dan MER menandakan kebolehpercayaan dan kualiti sistem komunikasi. Persembahan, BER dan MER daripada 4-, 8-, 16- dan 64-QAM menggunakan saluran AWGN, Rayleigh dan Ruis yang disiasat dan dianalisis. Ciri-ciri dan kesan saluran pudar AWGN, Rayleigh dan Rician juga diperiksa dan dibandingkan. Objektif projek ini termasuk merangka model QAM untuk membandingkan 4-, 8-, 16- dan 64-QAM di bawah AWGN dan saluran pudar (Rayleigh dan Rician), mengkaji kesan saluran yang berbeza (AWGN, Rayleigh dan Rician fading) pada model BER dan MER model VAM (4-, 8-, 16- dan 64-QAM) dan menyiasat kesan nilai SNR yang berbeza pada BER of M-ary QAM di bawah saluran AWGN dan Rayleigh. MATLAB Simulink digunakan untuk merekabentuk model QAM M-ary dan mensimulasikan model dengan saluran wayarles yang berbeza. Diagram mata isyarat M-ary QAM dalam tiga saluran juga diperiksa. Kemudian, hasil yang diperoleh dibandingkan dan dibincangkan. Dari hasil yang diperoleh, 4-QAM mempunyai prestasi terbaik dengan BER sama dengan 0.002997 dan MER sama dengan 8.293dB untuk saluran AWGN manakala 64-QAM mempunyai prestasi terburuk dengan BER sama dengan 0.988 dan MER sama dengan -10.55dB untuk saluran pudar Rayleigh. Di antara tiga saluran tanpa wayar, AWGN mempunyai prestasi terbaik, saluran Rician datang diikuti oleh saluran Rayleigh.
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Digital modulation gains popularity and massive attentions from every single corner of today’s world. Among the digital modulation techniques, QAM is extensively used and its applications helps to speed up data communication, for example data exchange and transfer. BER and MER signify the reliability and quality of the communication system. The performances, BER and MER of 4-, 8-, 16- and 64-QAM using AWGN, Rayleigh and Rician fading channels are investigated and analysed. The properties and effects of AWGN, Rayleigh and Rician fading channels are also examined and compared. The objectives of this project include designing a QAM model to compare 4-, 8-, 16- and 64-QAM under AWGN and fading channels (Rayleigh and Rician), examining the effect of different channels (AWGN, Rayleigh and Rician fading) on the BER and MER of QAM variants model (4-, 8-, 16- and 64-QAM) and investigating the effect of different SNR values on the BER of M-ary QAM under AWGN and Rayleigh fading channel. MATLAB Simulink is used to design the M-ary QAM model and simulate the model with different wireless channels. The eye diagrams of the M-ary QAM signals in the three channels are also inspected. Then, the results obtained are compared and discussed. From the results obtained, 4-QAM has the best performance with BER equals 0.002997 and MER equals 8.293dB for AWGN channel whilst 64-QAM has the worst performance with BER equals 0.988 and MER equals -10.55dB for Rayleigh fading channel. Among the three wireless channels, AWGN has the best performance, Rician channel comes in second followed by Rayleigh channel.
Development and simulation of m-ary qam generated signals in different channels using simulink / Ng Jen Yu