UAS Integration Research Act of 2023 This bill requires the Federal Aviation Administration (FAA) to enter into contracts to demonstrate or validate technology related to the integration of unmanned aircraft systems (UAS) into the national airspace system. The FAA must solicit proposals from applicants who describe a project that relates to a topic of interest identified by the FAA, demonstrate technical merit, and involve a contract with a test range. The FAA must also identify topics of interest related to the integration of UAS into the national airspace, including detect and avoid capabilities, beyond visual line of sight operations, UAS traffic management, and UAS safety standards. The bill also extends the authority for the FAA's UAS Test Site Program though FY2028. The program provides verification of the safety of public and civil UAS, operations, and related navigation procedures before their integration into the national airspace system.