This paper describes a new technique of efficient coding of high-frequency signal components as an alternative to
Spectral Band Replication. The main idea is to reconstruct the high frequency harmonic structure trajectories by
using fundamental frequencies obtained at the encoder side. Audio signal is decomposed into narrow subbands by
demodulation based on the local instantaneous frequency of individual partials. High frequency components are
reconstructed by modulation of the baseband signals with appropriately scaled instantaneous frequencies. Such
approach offers correct synthesis of rapidly changing sinusoids as well as proper reconstruction of harmonic
structure in the high-frequency band. This technique performs also a correct energy adjustment of sinusoidal
partials. High compression efficiency has been achieved and confirmed by listening tests.