Calibration of speech data acquisition path

A method of calibrating the data acquisition path for each utterance comprising the steps of:

• applying a voice utterance signal simultaneously to two speech transmission paths where the first path is a high quality reference path and a second test path being the acquisition path;
• detecting output power density of the reference path to produce signal YR and detecting output power density of the second test path to produce the power density of the mismatch signal YN;
• determining for each frame of the utterance the power spectrum for YR and YN;
• calculating for all of the frames of the utterance the following
• A(P×P)Δ[A1,A2, . . . AP]t B(P×Q)Δ[B1,B2, . . . BP]t C(Q×P)Δ[C1,C2, . . . CQ]t=BT
• D(Q×Q)Δ[D1,D2, . . . DQ]t uΔ[u1,u2, . . . up]t with up=α(p−1,YRYN) vΔ[υ1,υ2, . . . υQ]t with υq=β(q−1,YN)
• for A, B, C, D, u and v;
• calculating for the utterance the noise estimate θN using the following:
• (D−BtA−1B)θN=v−BtA−1u;
• and calculating for the utterance the channel estimate θH using the following:
• θH=A−1(u−BθN).

A method of calibrating the data acquisition path for each utterance comprising the steps of:

• applying a voice utterance signal simultaneously to two speech transmission paths where the first path is a high quality reference path a high and a second test path being the acquisition path to produce the mismatch signal YN;
• determining for each frame of the utterance the power spectrum for YR and YN;
• calculating for all of the frames of each utterance the following
• A(P×P)Δ[A1,A2, . . . AP]t B(P×Q)Δ[B1,B2, . . . BP]t C(Q×P)Δ[C1,C2, . . . CQ]t=BT D(Q×Q)Δ[D1,D2, . . . DQ]t uΔ[u1,u2, . . . up]t with up=α(p−1,YRYN) vΔ[υ1,υ2, . . . υQ]t with υq=β(q−1,YN)
• for A, B, C, D, u and v;
• calculating the noise estimate θN and the channel estimate θH using the following:
• 19 [ A B C D ] ⁢ [ θ H θ N ] = [ u v ] .

A data acquisition path calibration device comprising:

• a first speech transmission path including a high quality microphone and pre-A/D processing and a second test acquisition path including a lower quality microphone;
• means for detecting for each frame the power spectrum density of an input signal received over said first path to produce a reference signal YR and for detecting for each frame the power spectrum density of said input signal received over said acquisition path to produce mismatch signal YN
• means for determining the noise estimate and the channel estimate by calculating for each utterance:
• A(P×P)Δ[A1,A2, . . . AP]t B(P×Q)Δ[B1,B2, . . . BP]t C(Q×P)Δ[C1,C2, . . . CQ]t=BT D(Q×Q)Δ[D1,D2, . . . DQ]t uΔ[u1,u2, . . . up]t with up=α(p−1,YRYN) vΔ[υ1,υ2, . . . υQ]t with υq=β(q−1,YN)
• for A, B, C, D, u and v;
• calculating for the utterance the noise estimate θN using the following:
• (D−BtA−1B)θN=v−BtA−1u;
• and calculating for the utterance the channel estimate θH using the following:
• θH=A−1(u−BθN).

A data acquisition path calibration device comprising:

• a first speech transmission path including a high quality microphone and pre-A/D processing and a second test acquisition path including a lower quality microphone;
• means for detecting for each frame the power spectrum density of an input signal received over said first path to produce a reference signal YR and for detecting for each frame the power spectrum density of said input signal received over said acquisition path to produce mismatch signal YN
• means for determining the noise estimate and the channel estimate by calculating for each utterance:
• A(P×P)Δ[A1,A2, . . . AP]t B(P×Q)Δ[B1,B2, . . . BP]tC(Q×P)Δ[C1,C2, . . . CQ]t=BT D(Q×Q)Δ[D1,D2, . . . DQ]t uΔ[u1,u2, . . . u9]t with up=α(p−1,YRYN) vΔ[υ1,υ2, . . . υQ]t with υq=β(q−1,YN)
• for A, B, C, D, u and v;
• calculating the noise estimate θN and the channel estimate θH using the following:
• 20 [ A B C D ] ⁢ [ θ H θ N ] = [ u v ] .