Multidimensional parameters and MIMO (1/2) For optimum antenna/space diversity performance the received signal at the different antennas should be incorrelated,i.e.the signal envelope should have fast changes with space (along s). Therefore the power-angle profile should be very spread-there must be a large angle spread. To achieve good spatial multiplexing there must be a large number of strong paths well spaced(independent)in the angle domain in order for the MIMO matrix to have high rank-there must be a large angle spread. In other words there must be a high multipath richness Also absolute-time and Doppler domains(not considered here)are very important for space-time coding,i.e.transmit diversity and other MIMO coding techniquesMultidimensional parameters and MIMO (1/2) For optimum antenna/space diversity performance the received signal at the different antennas should be incorrelated, i.e. the signal envelope should have fast changes with space (along s). Therefore the power-angle profile should be very spread → there must be a large angle spread. To achieve good spatial multiplexing there must be a large number of strong paths well spaced (independent) in the angle domain in order for the MIMO matrix to have high rank → there must be a large angle spread. In other words there must be a high multipath richness Also absolute-time and Doppler domains (not considered here) are very important for space-time coding, i.e. transmit diversity and other MIMO coding techniques