Hearing device having bilateral beamforming with binaural cues
A hearing device comprises: a transceiver module configured to receive a contralateral directional input signal from the contralateral hearing device; a first BTE microphone for provision of a first BTE microphone input signal; a second BTE microphone for provision of a second BTE microphone input signal; a first MIE microphone for provision of a first MIE microphone input signal; a first beamformer for provision of a directional input signal based on the first BTE microphone input signal and the second BTE microphone input signal; a second beamformer for provision of a binaural beamform signal based on a binaural transfer function, the directional input signal, and the contralateral directional input signal; a spatializer for provision of a spatial binaural beamform signal based on the binaural beamform signal and a spatialization transfer function; and a processor configured to provide an electrical output signal based on the spatial binaural beamform signal.
1. A hearing device for a binaural hearing system, the hearing device comprising:
a transceiver module configured to communicate with a contralateral hearing device of the binaural system, the transceiver module configured to receive contralateral data from the contralateral hearing device, the contralateral data comprising a contralateral directional input signal;
a set of microphones comprising a first BTE microphone for provision of a first BTE microphone input signal, a second BTE microphone for provision of a second BTE microphone input signal, and a first MIE microphone for provision of a first MIE microphone input signal;
a first beamformer connected to the first BTE microphone and the second BTE microphone for provision of a directional input signal based on the first BTE microphone input signal and the second BTE microphone input signal;
a second beamformer connected to the first beamformer and the transceiver module for provision of a binaural beamform signal based on a binaural transfer function, the directional input signal, and the contralateral directional input signal;
a spatializer connected to the second beamformer for provision of a spatial binaural beamform signal based on the binaural beamform signal and a spatialization transfer function;
a processor configured to provide an electrical output signal based on the spatial binaural beamform signal; and
a receiver configured to provide an audio output signal based on the electrical output signal.
2. The hearing device according to claim 1 , wherein the second beamformer is connected to the first MIE microphone.
3. The hearing device according to claim 2 , wherein the second beamformer is configured to determine the binaural transfer function based on the first MIE microphone input signal from the first MIE microphone.
4. The hearing device according to claim 1 , wherein the binaural transfer function is based on the first MIE microphone input signal from the first MIE microphone.
5. The hearing device according to claim 1 , wherein the contralateral data comprises a contralateral MIE microphone input signal of a contralateral MIE microphone.
6. The hearing device according to claim 5 , wherein the binaural transfer function is based on the contralateral MIE microphone input signal.
7. The hearing device according to claim 1 , wherein the binaural beamform signal is given by:
V
=
F
L
H
+
F
R
(
1
-
H
)
,
wherein V is the binaural beamform signal, F L is the directional input signal, F R is the contralateral directional input signal, and H is the binaural transfer function, wherein H satisfies 0<H<1.
8. The hearing device according to claim 7 , wherein H is based on a minimization of a power of the binaural beamform signal.
9. The hearing device according to claim 1 , wherein the binaural beamform signal is given by:
V
=
max
(
F
L
,
F
R
)
H
+
min
(
F
L
,
F
R
)
(
1
-
H
)
,
wherein V is the binaural beamform signal, F L is the directional input signal, F R is the contralateral directional input signal, and H is the binaural transfer function.
10. The hearing device according to claim 1 , wherein the binaural beamform signal is given by:
V
=
max
(
F
L
,
F
R
)
M
+
min
(
F
L
,
F
R
)
(
1
-
M
)
,
wherein V is the binaural beamform signal, F L is the directional input signal, F R is the contralateral directional input signal, and M is a masking transfer function.
11. The hearing device according to claim 10 , wherein the masking transfer function is given by:
M
=
exp
(
-
c
(
β
-
H
)
)
,
wherein H is the binaural transfer function, c is a constant greater than zero, and β≥1.
12. The hearing device according to claim 10 , wherein the masking transfer function is given by:
M
=
exp
(
-
c
(
β
-
H
)
)
exp
(
-
c
(
β
-
H
)
)
+
exp
(
-
c
H
)
,
wherein H is the binaural transfer function, c is a constant greater than zero, and β≥1.
13. The hearing device according to claim 1 , wherein the binaural beamform signal is spatialized binaurally into the spatial binaural beamform signal based on:
V
L
=
❘
"\[LeftBracketingBar]"
V
❘
"\[RightBracketingBar]"
H
L
,
wherein V L is the spatial binaural beamform signal, V is the binaural beamform signal, and H L is the spatialization transfer function.
14. The hearing device according to claim 1 , wherein the binaural transfer function is given by:
H
=
min
(
P
R
,
P
L
)
max
(
P
R
,
P
L
)
,
wherein H is the binaural transfer function, P L is a power of the directional input signal, and P R is a power of the contralateral directional input signal.
15. The hearing device according to claim 1 , wherein the binaural transfer function is given by:
H
=
min
(
P
R
,
P
L
)
min
(
P
R
,
P
L
)
+
max
(
P
R
,
P
L
)
,
wherein H is the binaural transfer function, P L is a power of the directional input signal, and P R is a power of the contralateral directional input signal.
16. The hearing device according to claim 1 , wherein the spatialization transfer function is based on a power of the directional input signal, and a power of the contralateral directional input signal.
17. The hearing device according to claim 1 , wherein the spatialization transfer function is given by:
H
L
=
F
L
1
max
(
P
R
,
P
L
)
,
wherein H L is the spatialization transfer function, F L is the directional input signal, P L is a power of the directional input signal, and P R is a power of the contralateral directional input signal.
18. The hearing device according to claim 1 , wherein the spatialization transfer function is given by:
H
L
=
F
m
i
e
-
L
1
max
(
P
R
,
P
L
)
,
wherein H L is the spatialization transfer function, F mie-L is the first MIE microphone input signal, P L is a power of the directional input signal, and P R is a power of the contralateral directional input signal.
19. The hearing device according to claim 1 , wherein the spatialization transfer function is given by:
H
L
=
F
p
r
-
L
1
max
(
P
R
,
P
L
)
wherein H L is the spatialization transfer function, F pr-L is a pinna restoration signal, P L is a power of the directional input signal, and P R is a power of the contralateral directional input signal.
20. The hearing device according to claim 1 , wherein a power of the directional input signal and a power of the contralateral directional input signal are given by:
P
L
(
ω
,
n
+
1
)
=
γ
P
L
(
ω
,
n
)
+
(
1
-
γ
)
F
L
(
ω
,
n
)
F
L
*
(
ω
,
n
)
P
R
(
ω
,
n
+
1
)
=
γ
P
R
(
ω
,
n
)
+
(
1
-
γ
)
F
R
(
ω
,
n
)
F
R
*
(
ω
,
n
)
,
wherein P L is the power of the directional input signal, and P R is the power of the contralateral directional input signal, 0≤γ<1, ω is an angular frequency, and n is an integer.
21. The hearing device according to claim 1 , wherein the hearing device comprises a beamform controller for provision of the binaural transfer function and the spatialization transfer function.