Embodiments include an implant and a method of operating the implant. The implant includes a receiver that receives first ultrasound signals emitted by an external transmitting unit of a further apparatus. The receiver includes a piezoelement, which is excited by the first ultrasound signals at a first resonance frequency (f1) and therefrom converts the mechanical energy transferred with the first ultrasound signals into electrical energy. In embodiments of the invention, the piezoelement is additionally excited at a second resonance frequency (f2), which differs from the first resonance frequency (f1), and at the second resonance frequency (f2) operates as a transmitter to transmit second ultrasound signals.
