This conjugated signal is now transmitted back to the kth element which in turn retransmits it to the ground. The phase of the conjugated signal at the kth element at time t is obtained from (A5) in exactly the same way we obtained (A2) from (Al), viz. by subtracting [] from t throughout (A5) . Thus The phase of the conjugated signal arriving back at the pilot source (r = 0) at time t is where i.e. [] is the "downlink'’ phase delay of the path between the kth element and the pilot source at time t. Note that it differs from the uplink delay, [], in (A1) due to the motion of the kth element during the interval [].
RkJQdWJsaXNoZXIy MTU5NjU0Mg==