In a receiver, a synchronization circuit provides a set of oscillator signals that are synchronized with a carrier of an amplitude-modulated signal. One method includes transmitting a signal having a fixed modulation period towards a ground target and then detecting reflected signals off the ground target. The SiGe sourcedrain forms a heterojunction and a metallurgical junction with the Si body that coincide with each other with a tolerance of less than about 10 nm, and preferably less than about 5 nm. A process of changing the zoom factor and capturing an image is repeated until the smallest zoom factor among determined zoom factors is used.