Design and implementation of Alamouti encoder for 4G wireless system

Multiple-input multiple-output (MIMO) systems are called to play a crucial role in fourth Generation (4G) wireless systems to provide advanced data services. This paper addresses the design and implementation of a MIMO encoder that is based on Alamouti scheme on a Xilinxreg Virtextrade-4 XC4VLX60 Field Programmable Gate Arrays (FPGA) device. This encoder is a part of MIMO testbed, equipped with multiple antennas at both ends of the link which appropriately encodes the modulated symbols to achieve both time and spatial diversity. In this paper, a comprehensive explanation of the complete design process is provided, including an illustration of the tools used in its development. The encoder for the MIMO testbed is developed based on modular design which simplifies system design, eases hardware update and facilitates testing the various modules in an independent manner.