DSP emulator for OFDM communication via HAP with beamforming algorithms

One of the main limitations in testing beamforming algorithms for OFDM, using traditional simulation tools like Matlab, is represented by the difficulties in taking into account DAC/ADC degradations, sampling clock errors and other aspects specific of a true communication system. The use of a real smart antenna is normally constrained by high costs relative to the front-end implementation. In order to overcome these problems we have realized a prototype that exploits the audio interface of commercial DSPs to simulate an OFDM communication on a SIMO channel, allowing the use of beamforming algorithms at the receiver side. Projects involving DSPs and their audio interface have already been developed, but they do not use a smart antenna at the reception: this simulator is a low cost solution to study the feasibility of an OFDM transmission and to test beamforming algorithms in presence of impairments due to analog and digital conversions. The realized emulator represents a flexible and powerful tool that can be easily adapted to other contexts thanks to its modular architecture and its parametric nature.