An electronic device, and method, at a first communication apparatus having multiple antennas includes a memory for storing computer instructions; and a processing circuit configured to execute the stored computer instructions to: based on channel states of channels between the multiple antennas of the first communication apparatus and a second communication apparatus, determine channel characteristics of a first channel from the first communication apparatus to a second communication apparatus in an angle domain: based on the determined channel characteristics of the first channel in the angle domain, determine a first set of pilot signals used in the angle domain, the pilot signals in the first set of pilot signals being orthogonal to each other; and transform the first set of pilot signals into a second set of pilot signals for transmission over the multiple antennas of the first communication apparatus.