Certain aspects relate to methods and apparatus for identifying which antenna module is attached to a baseband module port at runtime. For example, an apparatus includes a first radio frequency (RF) module that generates first RF signals based on first intermediate frequency (IF) signals corresponding to a known sequence, and outputs the first RF signals for transmission via a first antenna element, a second RF module that obtains the first RF signals via a second antenna element and processes the first RF signals to generate second IF signals, and a baseband module having first and second ports and generates the first IF signals, to determine which port of the first or second RF modules is coupled to, based on at least one of the first or second IF signals, and to configure at least one of the first or second RF module, according to known configurations, based on the determination.