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41. 发明专利

JPH0613938A ECHO CANCELLER 失效
公开(公告)号：JPH0613938A
公开(公告)日：1994-01-21
申请号：JP16868292
申请日：1992-06-26
申请人： FUJITSU LTD
发明人： SAKAI YOSHIHIRO , KURIHARA HIDEAKI , UTSUGI KIYOSHI , KUGIMIYA JUNICHI , SAKAMOTO KEIZO
IPC分类号： H04B3/20
摘要： PURPOSE:To attain talking without causing a noise sound or howling by forming the echo canceller in two stages, allowing the front stage to cancel an echo of a direct component and allowing the post stage to eliminate a reverberation component. CONSTITUTION:A tap coefficient of a filter of a 1st echo canceller 1 is selected so that the echo canceller 1 has an impulse response corresponding to a direct component inputted directly from a speaker 4 to a microphone 3. The direct component has a short reverberation time of the echo and number of taps is decreased. Furthermore, a 2nd echo canceller 2 erases a reverberation component having many tap numbers reflected in a wall or the like in a room unable to be eliminated by the 1st echo canceller 1. Then, the 1st echo canceller 1 erases the direct component having a largest component in the entire echo and having a short delay time, and when the output representing the result of elimination of the direct component is inputted to the 2nd echo canceller 2, the reverberation component being small having a large delay time is eliminated. Thus, the excellent echo cancellation quantity is attained from the start of the operation.

42. 发明专利

JPH0561499A VOICE ENCODING/DECODING METHOD 失效
公开(公告)号：JPH0561499A
公开(公告)日：1993-03-12
申请号：JP26711291
申请日：1991-09-18
申请人： FUJITSU LTD
发明人： KURIHARA HIDEAKI , TANIGUCHI TOMOHIKO , OTA TAKASHI , SAKAI YOSHIHIRO , TANAKA YOSHIAKI
IPC分类号： G10L19/08 , G10L19/00 , G10L19/04 , G10L19/12 , H03M7/30
摘要： PURPOSE:To curtail the arithmetic quantity by calculating a time inversion auditory sense weighing input sound signal vector and multiplying it by each pitch prediction residual vector of an adaptive code book generating a correlation value of both of them. CONSTITUTION:An arithmetic means 21 calculates a time inversion auditory sense weighting input sound signal vector AAX from an input sound signal vector AX subjected to auditory sense weighing. Also, a multiplying part 22 multiplies the time inversion auditory sense weighting input sound signal vector AAXC and each pitch prediction residual vector P of an adaptive code book 1 and generated a correlation value t(AP)AX of both of them. Subsequently, a filter arithmetic part 23 derives a self-correlation value (AP)AP of a vector AP after auditory sense weighting reproduction of each pitch prediction residual vector P of the adaptive code book 1. Moreover, an evaluating party 10 selects an optimal pitch prediction residual vector Popt and gain bopt for minimizing power of an error signal E to the input sound signal vector AX subjected to auditory sense weighting, based on both correlation values.

43. 发明专利

JPH04352199A SPEECH ENCODING AND DECODING SYSTEM 失效
公开(公告)号：JPH04352199A
公开(公告)日：1992-12-07
申请号：JP12779391
申请日：1991-05-30
申请人： FUJITSU LTD
发明人： KURIHARA HIDEAKI , TANIGUCHI TOMOHIKO , OTA TAKASHI , TANAKA YOSHIAKI , KATO MASAKO
IPC分类号： G10L19/04 , G10L19/00
摘要： PURPOSE:To provide the CELP type speech encoding and decoding systems which are greatly improved in speech quality. CONSTITUTION:The CELP type speech encoding system which performs the frame-by-frame vector quantization of an input signal AX by using an adaptive code book 1 and a stochastic code book 2 is equipped with a nonlinear conversion part 11 which performs the center clipping of the feedback quantity of a code vector component (g0, C0) of an optimum drive sound source signal (b0P0+g0C0) fed back to the adaptive code book 1 with a threshold value th corresponding to the follow-up extent of the adaptive code book 1. This threshold value th is determined on the basis of the ratio of the pitch or code vector component in the optimum drive sound source signal or a reproduced signal or the ratio of a pitch gain b0 and a code gain g0. Further, the CELP type decoding system is equipped with the same nonlinear conversion part 11 and has its threshold value th controlled by the same method with the encoding.

44. 发明专利

JPH04264600A VOICE ENCODER AND VOICE DECODER 失效
公开(公告)号：JPH04264600A
公开(公告)日：1992-09-21
申请号：JP2632791
申请日：1991-02-20
申请人： FUJITSU LTD
发明人： TANAKA YOSHIAKI , SAKAI YOSHIHIRO , SHIRAI YASUKO , TANIGUCHI TOMOHIKO , KURIHARA HIDEAKI
IPC分类号： G10L19/04 , G10L19/00 , G10L19/06 , G10L25/90
摘要： PURPOSE:To detect the error of pitch information in transmission line and to restore the error in a decoder side receiving transmitted pitch information by outputting information relating to the allowable limit of the value of a pitch period. CONSTITUTION:Inputted voice signal is subjected to predictive coding containing a long-term predictive analysis by a voice coding means 1 and outputted as information coded voice signal containing the pitch period analyzed by the long-term predictive analysis. Related to the pitch period within these bits of information, the information relating to the allowable limit of the value of the pitch period with a prescribed width containing the value of the pitch period is outputted in an allowable limit information generating means 2. Then, this information relating to the allowable limit, as well, is multiplied, for instance, to be transmitted from a transmission means 3 with the information coded with the voice signal.

45. 发明专利

JPS63189936A FLOATING-POINT MULTIPLIER 失效
公开(公告)号：JPS63189936A
公开(公告)日：1988-08-05
申请号：JP2282987
申请日：1987-02-03
申请人： FUJITSU LTD
发明人： KURIHARA HIDEAKI
IPC分类号： G06F7/487 , G06F7/508 , G06F7/52
摘要： PURPOSE:To reduce the number of times of carry detection and to shorten arithmetic processing time by providing the titled multiplier with a rounding/ carry detecting circuit for detecting carry based on a carry signal obtained from a mantissa part and rounding. CONSTITUTION:A carry signal from a mantissa part arithmetic circuit 20, a mantissa part bit to be a multiplied result and a code bit from an exponential part arithmetic circuit 10 are supplied to the rounding/carry detecting part 30 to judge carry and rounding. The detecting circuit 30 corresponding to respective states, i.e. (1) when both carry and rounding are not included, (2) when only carry is generated, (3) when both rounding and carry are generated, and (4) when only rounding is executed, and controls selectors 291, 271 in the circuit 20 and the circuit 10. Consequently, the number of times of carry detection is only once, so that the arithmetic processing time can be shortened.

46. 发明专利

JPS6325741A DIGITAL SIGNAL PROCESSING CIRCUIT 失效
公开(公告)号：JPS6325741A
公开(公告)日：1988-02-03
申请号：JP16951386
申请日：1986-07-18
申请人： FUJITSU LTD
发明人： KURIHARA HIDEAKI , ITO AKIRA
IPC分类号： G06F11/28 , G06F11/22
摘要： PURPOSE:To perform the debug with high efficiency by reading the internal data when a debug error of the firmware of a digital signal processing circuit is detected. CONSTITUTION:A digital signal processing circuit contains an instruction means 1, an internal memory means 2, an arithmetic means 3, an input/output control means 4 which controls these means 1-3, and an external memory means 5. If the means 4 receives an internal data output signal from outside when a debug error occurs, the means 4 resets an output address generating means 6 to inhibit the input/output with outside. Thus the internal data on the means 2 is outputted to the means 5 via an address designated by the means 6. Thus it is possible to refer to the debug result.

47. 发明专利

JPH10222198A VOICE CODE DECODING DEVICE 失效
公开(公告)号：JPH10222198A
公开(公告)日：1998-08-21
申请号：JP2804497
申请日：1997-02-12
申请人： FUJITSU LTD
发明人： KURIHARA HIDEAKI , ITO MASATO
IPC分类号： G10L11/02 , G10L19/00 , H03M7/40 , H04M11/06 , G10L9/18 , G10L9/00
摘要： PROBLEM TO BE SOLVED: To provide a voice code decoding device of which miniaturization can be performed and power consumption can be reduced. SOLUTION: A sound scanning section 57 discriminates whether a channel inputting a voice signal or voice code to a voice coding/decoding device is sound or not based on sound information of a channel stored in a state control memory 50. And only when it is discriminated as sound, an allotting section 58 decides a processor number of a voice code decoding processor to be allotted to the channel. This processor number is inputted to an input data conversion section 33. The input data conversion section 33 transmits a voice signal or a voice code inputted through the channel to the voice coding/decoding processor corresponding to a processor number.

48. 发明专利

JPH07261869A POWER CONSUMPTION REDUCTION SYSTEM FOR DIGITAL SIGNAL PROCESSOR 失效
公开(公告)号：JPH07261869A
公开(公告)日：1995-10-13
申请号：JP4960394
申请日：1994-03-18
申请人： FUJITSU LTD
发明人： KURIHARA HIDEAKI , OBARA HIROSHI
IPC分类号： G06F1/04 , H04B7/26
摘要： PURPOSE:To reduce the power consumption of the digital signal processor(DSP) more. CONSTITUTION:The power consumption reduction system for the DSP which processes an analog signal into a digital signal in real time under program control is equipped with the DSP 6 which starts the digital signal processing in synchronism with a frame signal FP and enters clock stop mode under internal program control and a buffer memory 7 which is connected to the data input/output interface part of the DSP 6 and can process a request to access data generated outside while the DSP 6 is in the clock stop mode with the timing signal of the external access irrelevantly to the DSP 6. The buffer memory 7 preferably has storage capacity for external data of at least one frame. In another way, the buffer memory 7 has storage capacity for external data of

49. 发明专利

JPH05158500A VOICE TRANSMITTING SYSTEM 失效
公开(公告)号：JPH05158500A
公开(公告)日：1993-06-25
申请号：JP32451191
申请日：1991-12-09
申请人： FUJITSU LTD
发明人： OTA TAKASHI , TANIGUCHI TOMOHIKO , KURIHARA HIDEAKI , SAKAI YOSHIHIRO , KATO MASAKO , TANAKA YOSHIAKI
IPC分类号： G10L19/00 , G10L15/02 , G10L19/12 , H03M7/30 , H04B14/04
摘要： PURPOSE:To provide a voice coding system, which can decrease a calculated variable required for searching a noise code book and further can decrease memory capacity required for storing the noise code book, concerning the voice coding system using A-b-S type vector quantization for executing coding at the transmission velocity of 4-16Kb/s. CONSTITUTION:One kind of an N dimensional initial vector C0 to previously express a reference noise sequence respectively on a coding side and a decoding side and delta vectors DELTAC1-DELTACL-1 to express N dimensional delta noise sequences for (L-1) kinds of hierarchies are prepared as a delta code book 11, error is calculated due to the code vectors C0-C1022 for (2L-1) kinds of noise sequences successively in tree structure by respectively adding or subtracting the respective delta vectors DELTAC1-DELTACL-1 to or from the initial vector C0 for each hierarchy, and the optimum code vector to be finally decided is generated by storing the respective code vectors as the combination of each index information and the hierarchy in this arithmetic process.

50. 发明专利

JPH04352200A SPEECH ENCODING SYSTEM 失效
公开(公告)号：JPH04352200A
公开(公告)日：1992-12-07
申请号：JP12766991
申请日：1991-05-30
申请人： FUJITSU LTD
发明人： TANIGUCHI TOMOHIKO , OTA TAKASHI , KURIHARA HIDEAKI , TANAKA YOSHIAKI , SAKAI YOSHIHIRO
IPC分类号： G06F3/16 , G10L15/02 , G10L19/00 , H03M7/30
摘要： PURPOSE:To reduce the search arithmetic quantity and memory capacity of a code book by storing the code book with N-dimensional initial vectors and delta victors representing a reference noise string and representing code vectors in the noise string in a tree structure shape. CONSTITUTION:The initial vector C0 and (L-1) kind of delta vectors C1- CL-1 are stored in the delta code book 11 previously and the respective delta vectors are added to or subtracted from the initial vector, layer by layer to represent the code vectors C0-C1022 of 2L-1 kind of noise strings sequentially in the tree structure shape; and a zero vector is added to them, thereby representing 2 kind of code vectors C0-C1023. An error minimum noise string determination part 17 determines a code vector which minimizes error electric power. At this time, cross correlation and autocorrelation are represented as recurrence formulas and calculated by a cross-correlation arithmetic part 14 and an autocorrelation arithmetic part 15. Then a speech encoding part 18 outputs a code specifying this code vector to perform speech encoding.

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