Physical unclonable function (PUF) is an innovative primitive used for key generation and device authentication, which has promising applications for resource-limited scenarios such as satellite communication. However, the reliability of traditional PUF circuits is low and the power consumption is high. Maintaining reliability also requires high costs, which limits its practical application. This article proposes a multimode SRAM PUF based on a 55-nm CMOS process, which has a self-healing feature. By using a voltage tilt preselection mechanism, the unstable PUF cells can be detected and most of them can be healed by mode switching, thereby improving the reliability of the PUF and reducing the costs required for golden key screening tests. However, the total ionizing dose (TID) effect poses a threat to the PUF, which can significantly increase the bit error rate (BER). In this article, the radiation effect of the PUF is characterized and its mechanism is analyzed. Besides, by means of the self-healing and preirradiation temperature and voltage masking techniques, the radiation reliability of the proposed PUF can be improved avoiding traditional destructive testing. The experimental results demonstrate that the BER can be reduced to as low as 0.0183%, which is$345\times $lower than the raw BER, after irradiation up to 100 krad(Si). The proposed technique presents great potential for communication security in the aerospace environment.