How to write the code to plot these two figure by using matlab? error probability and data rate in MIMO

I want to use Matlab to plot these two figures,fig(a) is the error probability,and as we can see,the higher M is,the lower error probability it has in the same SNR . The fig(b) is data rate,the higher M is,the higher data rate it has.M is the antennas number

(a) error probability

(b) date rate

I believe there are some theoretical formula of error probability and the data rate in MIMO.However,i can't find the theoretical formula for error probability in MIMO,so can anyone give me some information about this?

I have found some formula about the data rate in MIMO

1.C=log2(1+G_T*ρ0*G_R)1.C=log2(1+G_T*ρ0*G_R),

ρ0ρ0 is SNR,and GTGT and GRGR are the gain of the transmitting and receiving antennas.However,i can't find the relation between the G_T and G_R and MM,so i can't plot the figure like the (b) shown.Does anyone know about their relation or know how to write the code to plot these two figures