Opportunities and challenges of noise suppression technology for radio pulsar timing array

Pulsar timing array (PTA) is a set of extremly stable millisecond pulsars with which their time of arrival (TOA) are used to detect low frequency gravitational waves.The timing noise reducing, or, minimizing the error of TOAs, uses several techniques to identify different origins of timingn noise and obtian the high precision timing results.We present a review of the statues of current PTAs, the types of timing noise and corresponding reducing methods, andanalyze the orgins of these timing noises and the effects of these noises on the timing.With the real FAST data, it is suggested that with such an unparallel sensitivity,both oppotunities and challenges exist in the pulsar timing studies.The construction and operation of more large-aperture radio telescopes will enhance both the sensitivity and sky coverage of the PTA,leading to greater opportunities for detecting low-frequency gravitational waves.