Abstract: An echo canceller, in which an adder adds a pseudo echo generated by an adaptive filter to an echo, so that the echo and the pseudo echo are canceled to each other, includes: a subband filter (8, 14) and a sampling converter (9, 15) for downsampling an audio signal; a selector switch (10, 16) which appropriately switches between a side performing the downsampling and another side performing fullband echo cancellation; and a tap arrangement controller (19) which optimizes a tap arrangement by using coefficients which are updated using a downsampled signal by the adaptive filter (11), the tap arrangement controller outputting the optimized tap arrangement to the adaptive filter (11) at time of the fullband echo cancellation.

Abstract: An echo canceller is capable of reducing echo feeling in a conversation even if a tone signal is input. The echo canceller of this invention judges whether a far-end input signal is a calling control tone signal or not, and if that is the case, resets a coefficient of an adaptive filter. An echo canceller of another aspect judges whether a far-end input signal is a predetermined kind of a tone signal or not, and stops the update of the coefficient of the adaptive filter if the result is affirmative and an amount of echo cancellation is not larger than a threshold value. Further, when the tone signal ends, the echo canceller compares amounts of echo cancellation before and after the end of the tone signal, in accordance with a result of the comparison, restart the update of the coefficient of the adaptive filter after resetting the coefficient of the adaptive filter, or restarts the update of the coefficient of the adaptive filter without resetting the coefficient of the adaptive filter.

Abstract: An information processing device having a function for efficiently debugging a parallel processing program by controlling snoop operation is provided. The information processing device is so configured that the following is implemented: the setting for receiving a snoop request from a central processing unit can be set at a snoop controller that controls snoop operation; and as the result of reception of a snoop request, a debug controller can stop multiple central processing units.

Abstract: An echo canceler uses an adaptive filter to remove an echo of an incoming far-end signal from an outgoing near-end signal in the presence of ambient noise, updating the filter coefficients while the far-end signal is active and the near-end signal is inactive. The near-end and far-end signals are also sampled to obtain data vectors, which are averaged to generate simulated near-end and far-end signals, from which substitute filter coefficients are calculated and updated while the far-end signal is silent, the substitute filter coefficients being used when the far-end signal becomes active again. The number of data vectors averaged is varied according to the ratio of echo power to ambient near-end noise power, or according to the echo attenuation ratio, thereby speeding up convergence of the filter coefficients. Data sampled while the near-end and far-end signals are both active are excluded from the updating process.

Abstract: A dynamically reconfigurable processor is provided having a wiring structure which enables flexible mapping of a program to the processor with a small wiring area. A first wire permits a first arrangement of circuit blocks and a second wire provided for changing the arrangement order of the circuit blocks. A switch is provided to switch between the first wire and the second wire. By virtue of this arrangement, a greater variety of calculations can be performed in the circuit without the necessity for increasing the number of operation blocks.

Abstract: An echo canceller can efficiently remove the offset component from a voice call that can use an audio signal of a communication band wider than the conventional band and can provide a stable call with high communication quality.

Abstract: A band recovering device recovers frequency components lying in a frequency band lost due to band-limitation of a sound signal. The device includes a peak-limiting amplifier for amplifying an input narrow-band signal while preventing the resulting amplified signal from exceeding a maximum amplitude. A peak-limitation detector detects the level of the amplified signal output. An amplification controller increases the amplification factor and/or the amount of amplification of the peak-limiting amplifier in accordance with the level of the amplified signal. A band recovering circuit generates, based on the amplified signal output from the peak-limiting amplifier and input narrow-band signal, a band-recovered signal including the frequency components lying in the missing band.

Abstract: An echo canceller which can respond to a sudden change in echo characteristics in real time and does not require an alteration outside the echo canceller, includes a smoothed sending-speech signal calculation means for calculating a smoothed sending-speech signal from the sending-speech signal, the smoothed sending-speech signal being obtained by smoothing the sending-speech signal; a smoothed receiving-speech signal calculation means for calculating a smoothed receiving-speech signal from the receiving-speech signal, the smoothed receiving-speech signal being obtained by smoothing the receiving-speech signal; a delay time information generation means for obtaining delay time information reflecting delay characteristics of an echo path in accordance with a correlation between the smoothed sending-speech signal and the smoothed receiving-speech signal; and an update information generation means for obtaining update information indicating execution or suspension of updating of the tap coefficients of the adapti

Abstract: An echo canceler uses an adaptive filter to remove an echo of an incoming far-end signal from an outgoing near-end signal. Filter coefficients are calculated and updated while the far-end signal is active so as to minimize the residual echo. In addition, the far-end signal and near-end signal are sampled to generate simulated far-end and near-end signals, from which substitute filter coefficients are similarly calculated while the far-end signal is silent. When the far-end signal changes from silent to active, the substitute filter coefficients are swapped in as initial values for the filter coefficients, thereby speeding up subsequent convergence of the filter coefficients without significant added computational cost.

Abstract: A communication system 100 connects a plurality of terminals and the communication control unit 101 via a network 110. A group information table 203 of the communication control unit 101 has a that stores identification information of terminal belonging to a group capable of refusing receipts of information transmitted from an originator's terminal relative to identification information of that group and stores identification information of the originator's terminal relative to identification information of the group. A collation judging section 205 judges whether to refuse the receipt from the originator's terminal by collating whether the originator's terminal is registered relative to the group to which the recipient's terminal belongs by using the group information table 203. A communication control section 201 stops or connects the communication between the originator's terminal and the recipient's terminal to refuse or allow the receipt based on the judgment result.

Abstract: A band recovering device recovers frequency components lying in a frequency band lost due to band-limitation of a sound signal. The device includes a peak-limiting amplifier for amplifying an input narrow-band signal while preventing the resulting amplified signal from exceeding a maximum amplitude. A peak-limitation detector detects the level of the amplified signal output. An amplification controller increases the amplification factor and/or the amount of amplification of the peak-limiting amplifier in accordance with the level of the amplified signal. A band recovering circuit generates, based on the amplified signal output from the peak-limiting amplifier and input narrow-band signal, a band-recovered signal including the frequency components lying in the missing band.

Abstract: An uncomfortable feeling due to lack of the speech of a far end speaker and a convergence signal voice (sound) is prevented, and the echo of the far end speaker is removed. A pseudo signal generating circuit has a phase inverter (10) for inverting the phase of a signal, a pseudo hybrid circuit (11) for generating a pseudo echo having the same or substantially the same characteristic as that of the true signal, and a pseudo telephone set (5-2). By generating a pseudo echo having the phase opposite to that of the true signal and having the same or substantially the same characteristics as that of the true signal, the uncomfortable signals (echo, etc.) are cancelled out. When a telephone set is connected to a caller or when an extension transfer occurs, an adaptive filter convergence signal is generated for a predetermined constant time only during “no-voice (sound) (silence)” of the far end speaker's signal.

Abstract: Circuitry and a method compensate the erasure of speech signal data or similar periodic signal data, by substitution using past periodic signal data input. After a predetermined number of latest periodic signal data have been saved, whether or not an erasure occurs is determined with every periodic signal data sequence, which is a unit of processing. When an erasure occurs, one of periodic signal data sequences saved, which lies in a determined segment to be used, is used to generate synthetic data for substitution. The position of the segment to be used is determined such that when the erasure continues over units of processing, the position sequentially varies gradually for each processing units.

Abstract: A band recovering device recovers frequency components lying in a frequency band lost due to band-limitation of a sound signal. The device includes a peak-limiting amplifier for amplifying an input narrow-band signal while preventing the resulting amplified signal from exceeding a maximum amplitude. A peak-limitation detector detects the level of the amplified signal output. An amplification controller increases the amplification factor and/or the amount of amplification of the peak-limiting amplifier in accordance with the level of the amplified signal. A band recovering circuit generates, based on the amplified signal output from the peak-limiting amplifier and input narrow-band signal, a band-recovered signal including the frequency components lying in the missing band.

Abstract: A dynamically reconfigurable processor having a wiring structure which enables flexible mapping of a program to the processor with a small wiring area is provided. The dynamically reconfigurable processor comprises: a first arithmetic circuit group composed of arithmetic circuits of a type Ai (i=1, 2, . . . , N); a second arithmetic circuit group composed of a part of an arithmetic circuit group included in the first arithmetic circuit group and an arithmetic circuit group of a type B which is connected thereto and different from the arithmetic circuit of the type Ai; inter-arithmetic-circuit wires mutually connecting the arithmetic circuits of the type Ai and the arithmetic circuits of the type B; and a switch group which causes the inter-arithmetic-circuit wires in the second arithmetic circuit group to be inter-arithmetic-circuit wires different from other inter-arithmetic-circuit wires and changes the connection order between the arithmetic circuits in the second arithmetic circuit group.

Abstract: An echo canceller can efficiently remove the offset component from a voice call that can use an audio signal of a communication band wider than the conventional band and can provide a stable call with high communication quality.

Abstract: There is provided an echo canceller which can appropriately cancel an echo even when a low-frequency component is included in the signal to be passed. The echo canceller includes an echo replica forming means for forming an echo replica signal from a far-end input signal by using an adaptive filter including a filter section and a coefficient update section, and an echo cancellation means for removing an echo component in a near-end input signal by subtracting the echo replica signal from the near-end input signal. The echo canceller further includes an offset removal means for removing an offset component produced under an effect of low frequencies from the filter coefficient of the adaptive filter.

Abstract: Circuitry and a method compensate the erasure of speech signal data or similar periodic signal data, by substitution using past periodic signal data input. After a predetermined number of latest periodic signal data have been saved, whether or not an erasure occurs is determined with every periodic signal data sequence, which is a unit of processing. When an erasure occurs, one of periodic signal data sequences saved, which lies in a determined segment to be used, is used to generate synthetic data for substitution. The position of the segment to be used is determined such that when the erasure continues over units of processing, the position sequentially varies gradually for each processing units.

Abstract: In a dynamic reconfigurable processor, a mechanism for effectively storing configuration data with a small hardware scale and improving processing performance is provided. Also, a sequence mechanism that is easy to be implemented with flexibility and a high operating frequency being both achieved is provided. The configuration data is hierarchically stored, and without suspending a process in a processing unit, configuration data required for subsequent processing is transferred in advance from a first storage area to a second storage area. Also, with a plurality of sequence modes, a condition determination process is performed on different sequence conditions.

Abstract: There is provided at least one processor block including a plurality of load store interfaces (801, 804), a plurality of memory banks (821), an input/output port having at least one of an input port (850) and an output port (860), and a crossbar switch (810), and the crossbar switch connects the load store interface, the memory bank and the input/output port to each other and the load store interface constitutes a data processor in order to control a data transfer to the memory bank. Consequently, there is implemented a data processor having a high transfer throughput and a flexibility and efficiently treating stream data.