Voice-to-remaining audio (VRA) interactive hearing aid and auxiliary equipment

Abstract

An integrated individual listening device and decoder for receiving an audio signal including a decoder for decoding the audio signal by separating the audio signal into a voice signal and a background signal, a first end-user adjustable amplifier coupled to the voice signal and amplifying the voice signal; a second end-user adjustable amplifier coupled to the background signal and amplifying the background signal; a summing amplifier coupled to outputs of said first and second end-user adjustable amplifiers and outputting a total audio signal, said total signal being coupled to an individual listening device.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. provisional patent application Ser. No. 60/139,243 entitled “Voice-to-Remaining Audio (VRA) Interactive Hearing Aid & Auxiliary Equipment,” filed on Jun. 15, 1999.

Ideally, the hearing aid (H) will invert the hearing impairment, G₃. Therefore the last three terms where both G₃ and H appear, will have, those coefficients to be approximately one. The resulting equation is then
w₂S+w₁d+G₃G₂d+G₃G₂G₁S+w₁G₁S
This does not provide the sound quality needed. While the desired and decoder signals do have level adjustment capability, the last three terms will deliver significant levels of distortion and latency both through the electrical and physical signal paths. The desired result is a combination of the pure decoder signal and the desired ambient audio signal where the end-user can control the relative mix between the two with no other signals in the output. The variables “S” and “d+G₁S” are available for direct measurement and the values of H, w₁, and w₂ are controllable by the end-user. This combination of variable permits the adjustment capability desired. If the adaptive filter and the plant estimate (G₂ hat) are now included in the equation for the output to the end end-user's nerve, it becomes:
w₁d+w₂G₁S+w_AFS+G₃G₂(d+G₁S)−G₃(G₂hat)(d+G₁S)

Now, if the adaptive filter converges to the optimal solution, it will be identical to G₁ so that the third and fourth terms in the above equation cancel. And if the estimate of G₂ approaches G₂ due to a good system identification, the last two terms in the previous equation will also cancel. This leaves only the decoder signal “S” end-user modified by w₂ and the desired ambient sound “d” end-user modified by w₁, the desired result. The limits of the performance of this method depend on the performance of the adaptive filter and on the accuracy of the system identification from the outside of the hearing aid to the inside of the hearing aid while the end-user has it comfortably in position. The system identification procedure itself can be carried out in a number of ways, including a least mean squares fit.

Interception Box

FIG. 11 illustrates another embodiment according to the present invention. FIG. 11 shows the features of a VRA set top terminal used for simultaneously transmitting a VRA adjustable signal to multiple end-users.

VRA set top terminal 60 includes a decoder 61 for decoding a digital bitstream supplied by a digital source such as a digital TV, DVD, etc. Decoder 61 decodes the digital bitstream and outputs digital signals which have a preferred audio component (PA) and a remaining audio portion (RA). The digital signals are feed into a digital-to-analog (D/A) converters 62 and 69 which converts the digital signals into analog signals. The analog signals from D/A converter 62 are feed to transmitter 63 to be transmitted to receivers such as receivers 270 shown in FIG. 5. Thus, multiple end-users with individual listening devices can adjust the voice-to-remaining audio for each of their individual devices. The output from D/A converter 69 is sent to a playback device such as analog television 290.

FIG. 12 illustrates an alternative embodiment of the present invention. Like in FIG. 11, a bitstream is received by decoder 61 of VRA set-top-terminal 60. Decoder outputs digital signals which are sent to D/A converter 62. The output of D/A converter 62 are analog signals sent to transmitter 63 for transmission of these signals to receivers 270. D/A converter 62 also feeds its output analog signals to variable amplifiers 225 and 226 for end-user adjustments before being downmixed by summer 227. This output signal is feed to analog television 290 in a similar manner as discussed above with respect to FIG. 11 but already having been VRA adjusted. According to this embodiment of the present invention, not only will hearing impaired end-users employing receivers 270 enjoy VRA adjustment capability, but end-users listening to analog television will have the same capability.

While many changes and modifications can be made to the invention within the scope of the appended claims, such changes and modifications are within the scope of the claims and covered thereby.

Claims

1. A set-top-terminal for providing voice-to-remaining audio capability comprising:

a decoder for decoding a bitstream and producing as its output, a digital preferred audio signal and a said digital remaining audio signal;

a digital to analog (d/A) converter coupled to said decoder, said d/A converter converting said digital preferred audio signal and a digital remaining audio signal into an analog preferred audio signai and an analog remaining audio signal;

a transmitter coupled to said d/A converter and transmitting said analog preferred audio signal and said analog remaining audio signal;

a first end-user adjustable amplifier coupled to said analog preferred voice signal and amplifying said analog preferred voice signal;

a second end-user adjustable amplifier coupled to said analog remaining audio signal and amplifying said analog remaining audio signal; and

a summer coupled to outputs of said first and second end-user adjustable amplifiers and outputting a total audio signal.

2. The set-top-terminal of claim 1, wherein an output of the summer outputting said total audio signal is coupled to an analog receiving device.

3. A method for processing a digital bitstream from a set-top terminal, comprising:

decoding a bitstream to produce a digital preferred audio signal and a digital remaining audio signal;

converting said digital preferred audio signal and said digital remaining audio signal into an analog preferred audio signal and an analog remaining audio signal;

transmitting said analog preferred audio signal to a first end-user adjustable amplifier coupled to receive said analog preferred audio signal and said analog remaining audio signal to a second end-user adjustable amplifier coupled to receive said analog remaining audio signal;

amplifying said analog preferred voice signal with said first end-user adjustable amplifier;

amplifying said analog remaining audio signal with said second end-user adjustable amplifier; and

summing output from said first and second end-user adjustable amplifiers and outputting a total audio signal to an individual listening device.

4. The method of claim 3, wherein outputting said total audio signal includes outputting said total audio signal to an analog receiving device.

5. The method of claim 3, further comprising:

employing a microphone incorporated into a listening device to detect an ambient environmental sound; and

further processing the digital bitstream based on detected ambient environmental sound.