This paper presents the design of an 8 × 8 Multiple-Input Multiple-Output (MIMO) hardware simulator for cooperative time-varying propagation channels (based on relays) using heterogeneous systems (LTE-A and 802.11ac) with Visible Light Communications (VLC) signals. The simulator reproduces a desired radio channel scenario and makes it possible to test “on table” different systems. It uses different impulse responses to cover many types of channels by merging TGn models, 3GPP-LTE models, outdoor-to-indoor measurements results and VLC models. An algorithm is introduced to convert the measured impulse responses from 200 MHz sample frequency to 50 MHz to be compatible with LTE-A signals. A specific architecture of the simulator digital block is presented to characterize 5G scenarios. The architecture is designed on a Xilinx Virtex-VII XC7VX690T Field Programmable Gate Array (FPGA). Its accuracy and FPGA occupation are analyzed.