A QAM signal has the mathematical form given below: Ym (t) = Im.cos(wet) - Qm. sin(wet)...

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A QAM signal has the mathematical form given below: Ym (t) = Im.cos(wet) - Qm. sin(wet) ym (t) = Am1.cos(wet + m2) Where: Im and Qm are the in-phase carrier weightings (cos() carrier) and quadrature carrier weightings (sin() carrier) respectively that combine to form the modulated signal. To modulate this, the quadrature modulation system in Figure 1 needs to be implemented (use MATLAB to do this). cos(@_t) K/2-bit d[n] Serial to R. bps parallel converter Digital to Analogue Converter M = 2* levels Digital to Analogue Converter I, 772 X X ? sin(@t) Figure 1: A quadrature modulation systems for MQAM m 1₁(t) + Q₁(t) + y; (t) This system takes the binary sequence (ones and zeros), d[n] and converts this into two branches with k/2 bits per branch (e.g. for 4-QAM with 2 bits/symbol 1 bit will be routed up and 1 down). For each branch the in-phase (Im) and quadrature (Qm) weights are generated before being modulated onto the quadrature carriers (cos(wet) and sin(wct)). Finally, these modulated signals are combined by subtracting the quadrature branch away from the in-phase and then transmitting through a channel. A QAM signal has the mathematical form given below: Ym (t) = Im.cos(wet) - Qm. sin(wet) ym (t) = Am1.cos(wet + m2) Where: Im and Qm are the in-phase carrier weightings (cos() carrier) and quadrature carrier weightings (sin() carrier) respectively that combine to form the modulated signal. To modulate this, the quadrature modulation system in Figure 1 needs to be implemented (use MATLAB to do this). cos(@_t) K/2-bit d[n] Serial to R. bps parallel converter Digital to Analogue Converter M = 2* levels Digital to Analogue Converter I, 772 X X ? sin(@t) Figure 1: A quadrature modulation systems for MQAM m 1₁(t) + Q₁(t) + y; (t) This system takes the binary sequence (ones and zeros), d[n] and converts this into two branches with k/2 bits per branch (e.g. for 4-QAM with 2 bits/symbol 1 bit will be routed up and 1 down). For each branch the in-phase (Im) and quadrature (Qm) weights are generated before being modulated onto the quadrature carriers (cos(wet) and sin(wct)). Finally, these modulated signals are combined by subtracting the quadrature branch away from the in-phase and then transmitting through a channel.

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To implement the quadrature modulation system for MQAM in MATLAB you can follow these steps 1 Define the parameters Set the modulation order M eg 4 fo... View the full answer