Achievable Rates of IID Gaussian Symbols on the Non-Coherent Block-Fading Channel Without Channel Distribution Knowledge at the Receiver

Consider receivers that do not exploit any knowledge of the channel distribution in non-coherent block-fading multiple-input multiple-output (MIMO) channels. The main contribution of this letter is to derive a semi-analytical semi-numerical lower bound to the achieveble rate of such receivers. The bound is of operational meaning since practical receivers can achieve the lower bound. Several numerical examples with Gaussian block fading channels, which illuminate that the lack of channel distribution at the receiver imposes a significant penalty if the coherence time (counted in symbol times) is not much larger than the number of transmit antennas, are provided.