Implementation of Alamouti Encoder Using FPGA for Mimo Testbed

Multiple-input multiple-output (MIMO) is a generic technique that promises to be a strong contender for 4G wireless systems. This paper presents the design and implementation of a space time block coding (STBC) 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 element antennas (MEA) at both ends of the link. The task of this Alamouti encoder is to appropriately encode 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, reduces development time, eases hardware update and facilitates testing the various modules in an independent manner.