A phased-array includes, in part, N transceivers each including a receiver and a transmitter, and a controller. The phased array is configured to transmit a first radio signal from a first element of the array during a first time period, receive the first radio signal from a second element of the array, recover a first value associated with the radio signal received by the second element, transmit a second radio signal from the second element of the array during a second time period, receive the second radio signal from the first element of the array, recover a second value associated with the radio signal received by the first element, and determine a first phase of a reference signal received by the second element from the recovered first and second values. The first phase is relative to a second phase of the reference signal received by the first element.