Hearing device comprising a gsc beamformer

A hearing device comprising

• a microphone array for picking up sound from a sound field including a target sound source in the environment of the hearing device, the microphone array comprising a number M of microphones for picking up each their version of the sound field around the hearing device and providing M electric input signals, a look vector d(k) being defined as an M-dimensional vector comprising elements dm(k), m=1, 2, . . . , M, the mth element dm(k) defining an acoustic transfer function from the target signal source to the mth microphone, or a relative acoustic transfer function from the mth microphone to a reference microphone, where k is a frequency index,
• A look vector unit for providing an estimate dest(k) of the look vector d(k) for the currently relevant target sound source,
• a generalized sidelobe canceller for providing an estimate e(k,n) of a target signal s(k,n) from said target sound source, where n is a time index, a target direction being defined from the hearing device to the target sound source, the generalized sidelobe canceller comprising
• an all-pass beamformer configured to leave all signal components from all directions un-attenuated, and providing all-pass signal yc(k,n), and
• a target-cancelling beamformer configured to maximally attenuate signal components from the target direction, and providing target-cancelled signal vector yb(k,n), where yb(k,n)=[yb,1(k,n), . . . , yb,M-1(k,n)]T, and yb,i(k,n) is the ith target-cancelled signal,
• a scaling unit for generating a scaling vector h(k,n) applied to the target-cancelled signal yb(k,n) providing scaled, target-cancelled signal yb(k,n),
• a combination unit for subtracting said scaled, target-cancelled signal yn(k,n) from said all-pass signal yc(k,n), thereby providing said estimate e(k,n) of said target signal s(k,n),
• wherein the M electric input signals from the microphone array and the look vector unit being operationally connected to the generalized sidelobe canceller, and wherein
• the scaling unit is configured to provide that said scaling vector h(k,n) is made dependent on a difference Δi(k,n) between the energy of the all-pass signal yc(k,n) and target-cancelled signal yb,i(k,n), where i is an index from 1 to M−1.