Fast implementation of coherent dispersion compensation

The interstellar medium consists of gas and dust components, almost all of which are completely transparent at centimeter wavelengths. The main cause of radio wave scattering in the interstellar medium is ionized gas—plasma. The behavior of radio waves propagating through such a medium is described by the dispersion equation in a rarefied plasma. The plasma frequency is generally a function of position and time, because it depends on the electron density along the line of sight. The dispersion measure physically represents a column of free electrons between a pulsar and the Earth. Thus, the dispersion measure is a value that determines the delay of radiation pulses of cosmic objects. The delay of radio emission is due to the fact that the refractive index of the plasma depends on the wavelength. Long waves propagate more slowly than short ones, so a signal emitted simultaneously at different frequencies arrives to the observer at long waves later than at short ones. One type of astrophysical objects for which the pulse delay can be measured are pulsars. Since observations are always carried out in a certain wavelength band, the presence of a delay interferes with the study of the fine time structure of pulsar pulses. Without dispersion correction, pulsar observations in a wide frequency band become impossible. The presented work considers the implementation of the coherent dispersion compensation method on a heterogeneous computing structure. Processing in the spectral domain allows the simultaneous search for fast radio bursts (giant pulses), radio pulsars, and refinement of the dispersion measure of the found pulses. It is shown that the proposed implementation on modern computing accelerators allows real-time processing in a wide frequency band that meets modern requirements.