block_4by4_complex------------------This block is used for simulations of the channel. It implementsa NxM MIMO-system, where N and M are <= 4. One can give the size of the block in samples as well as theprecision of the A/D converter. The channel-matrix h[n][m] represents the channel between thetx-antenna (input) 'm' and the rx-antenna (output) 'n'. For the receiving-antenna you can give the sigma of the white noise.Please be aware that the sigma is between -32767 and 32767, and comparesto a signal-amplitude set by the modules (usually around 10000), whereasthe more conventional sigma compares to a signal-amplitude of 1.Inputs:	SYMBOL_COMPLEX[4]outputs:	SYMBOL_COMPLEX[4]Config:	double h[MAX_NO_RX][MAX_NO_TX]<complex>: 0.5 + 0.5j		channel entries over rows  	double sigma[MAX_NO_RX]<complex>: 100 + 100j		The sigma of the gaussian-noise at the receiver	precision<int>: 12		The precision of the A/D converter	size<int>: 2560		The number of symbols of the blockStats:	max_no_rx<int>:		The maximum number of reception antennas	max_no_tx<int>:		The maximum number of transmission antennas