A Hardware-In-Loop test bed for WIMAX downlink baseband processing using Simulink and field programmable gate arrays

A Hardware-In-Loop (HIL) approach involves using an embedded system such as an FPGA as a simulation device in a software environment such as Simulink. This accelerates the simulation time and also aids in rapid system prototyping for building a complete hardware model based on software algorithm design. A thorough study is needed to identify the design challenges that one faces in implementing a design based on this approach. WIMAX (Worldwide Interoperability for Microwave Access) is a fast emerging technology in modem wireless communications based on IEEE 802.16 standards for broadband wireless networks. Such a system design and its optimization are generally started using modeling tools such as Simulink. However, in the transition of the design from software environment to a hardware model, a HIL approach offers greater flexibility for design and test. Downlink Baseband Processing which is a part of a WIMAX transmitter model is implemented with the HIL approach on an FPGA and the rest of the transmitter and receiver blocks are implemented in Simulink. Thus, the HIL test bed provides significant convenience and flexibility for system level testing along with accelerating design development. Additionally, an audio filter design on FPGA which is developed for DSP curriculum in Computer Engineering using Altera’s DE2 FPGA Kits is also presented. A low pass filter is implemented on an FPGA device and its operation is tested using audio signals channeled thorough the FPGA development board’s audio codec --Abstract, page iv