FPGA Implementation of Phase Recovery Technique for Complex Transforms

Abstract

The ECG signals are one of the most important signals to check the human heart’s condition. On monitoring the heart continuously, a large amount of ECG signal data will be produced. So, there is a need for efficient compression techniques. Discrete Anamorphic Stretch Transform (DAST) is one of the most efficient techniques. It is a one-dimensional complex transform that includes the phase recovery technique for recovering the phase from the magnitudes. This paper deals with implementing the phase recovery block in Field Programmable Gate Array (FPGA), which will recover the phase by using magnitudes. Phase recovery block plays a key role in reconstructing the phases from the magnitudes. First, the required signal is passed through the linear filter or phase recovery filter. Then the phase value is estimated using a noniterative algorithm depending on the linearity and causality conditions. The new approach for the phase recovery block is also used for any complex signal transmission. The input ECG signal is taken from the MIT-BIH Arrhythmia database and implementation is carried out in Artix-7 NEXYS 4 DDR FPGA Board. The performance of the phase recovery block is quantified in terms of hardware and computational complexity.