Performance Evaluation of Orthogonal Frequency Division Multiplexing using 16-bit Irregular Data Formats

Abstract

This report asserts that 16-bit Digital Signal Processing applications suffer from dynamic range and noise performance issues. This problem is highly common in complex DSP algorithms and is compounded if they are programmed in high level languages due to no native compiler support for 16-bit data formats. A solution to this problem is achieved by using 16-bit irregular data formats which show significant improvement over fixed and floating point approaches.
First, the data formatting problem for 16-bit programmable devices are defined and discussed. Existing solutions to the problem is taken into consideration. Then a new class of floating point numbers is obtained from which irregular data formats are derived. Attempts are made to derive format with greater dynamic range and noise performance.
Then the irregular data format along with fixed and floating point formats are simulated and analysed for simple DSP applications to make a performance analysis. Finally the data formats under consideration are implemented in a full-fledged Orthogonal Frequency Division Multiplexing model. The inputs and outputs obtained are compared for the percentage of error and final conclusions are drawn. The results indicate that irregular data formats have significant improvement over fixed and floating point formats and 16-bit DSP applications can be implemented in a more effective way using irregular data formats.