Abstract: A method and system for detecting a dual tone in a composite signal having first and second components including means for separating the composite signal into its first and second components, means for estimating power of the separated first and second components, means for determining frequency of the separated first and second components, and means for comparing the power and frequency of the first and second components to at least one of a plurality of respective power and frequency thresholds to determine whether the composite signal comprises a dual tone.

Abstract: An interactive remote auction bidding system for conducting an auction utilizes a data input device for communication over a network to the auction site. The system includes a data processor located at the auction site for generating bid information for communication over the network to the remote locations. A processor located at the auction side monitors the participants' data input devices for sensing participant bids generated by the participants' data input devices. The system further displays visual bid information at the auction site for transmission over the network to the participants and generates audible bid information in support of that visual bid information.

Abstract: An interactive remote auction bidding system for conducting an auction utilizes a data input device for communication over a network to the auction site. The system includes a data processor located at the auction site for generating bid information for communication over the network to the remote locations. A processor located at the auction side monitors the participants' data input devices for sensing participant bids generated by the participants' data input devices. The system further displays visual bid information at the auction site for transmission over the network to the participants and generates audible bid information in support of that visual bid information.

Abstract: A communication apparatus connected to a PBX and an ATM network is provided with a DTMF signal detecting portion for detecting whether or not a DTMF signal is contained in a voice signal from the PBX, a DTMF signal monitoring portion, a DTMF cell generating portion for coding and sending out a DTMF signal, a DTMF cell decomposing portion for decoding a coded DTMF signal and a DTMF signal generating portion for generating a DTMF signal on the basis of the information content of a decoded DTMF signal and sending out this DTMF signal to the PBX, and the transmission side communication apparatus codes a DTMF signal in a specified form and transmits the DTMF signal and the reception side communication apparatus decodes the coded DTMF signal and, on the basis of this content information, restores the DTMF signal in a DTMF signal generating portion.

Abstract: A communication apparatus connected to a PBX and an ATM network is provided with a DTMF signal detecting portion for detecting whether or not a DTMF signal is contained in a voice signal from the PBX, a DTMF signal monitoring portion, a DTMF cell generating portion for coding and sending out a DTMF signal, a DTMF cell decomposing portion for decoding a coded DTMF signal and a DTMF signal generating portion for generating a DTMF signal on the basis of the information content of a decoded DTMF signal and sending out this DTMF signal to the PBX, and the transmission side communication apparatus codes a DTMF signal in a specified form and transmits the DTMF signal and the reception side communication apparatus decodes the coded DTMF signal and, on the basis of this content information, restores the DTMF signal in a DTMF signal generating portion.

Abstract: A tone transmission part transmits a tone signal. A tone signal detection part detects data representing an echo signal of the tone signal transmitted by the tone transmission part, and detects data representing a predetermined tone signal targeted to be detected. The tone signal detection part also detects data representing tone signals of all of input signals. A tone judgment part excludes the data representing the echo signal from the data representing the tone signals of all of the input signals so as to judge a detection of the predetermined tone signal.

Abstract: A signal classifier decomposes a subject signal into subbands. The signal classifier then analyzes the subbands for a presence of energy and uses detection logic to classify the energy as being representative of a frame of a signal using one of the following protocols: DTMF, MF-R1, ANS (V.25), LEC-DIS, V.21, or AA (i.e., telephone, facsimile, or modem). The detection logic is expandable to detect future protocols. The classifier may employ a preclassifier to select a reduced number of notch filters from among plural notch filters at frequencies which sinusoidal signals composing the energy in the subbands of the protocols may be found. A look-up table having predetermined ranges of data corresponding to the frequencies of the sinusoidal signals may be used to reduce calculation times. By splitting the subject signal into subbands and using efficient filters, the classifier uses an order of magnitude fewer processor instruction cycles than previous classifiers.

Abstract: A multi-frequency tone detector with analysis window (i.e. filter size) chosen such that spectral nulls are located at adjacent frequencies of interest. The decision logic block of the tone detector uses the roll-off characteristics of the filter in conjunction with background noise to determine a threshold pass/fail for any tone that has deviated excessively from its nominal value. The foregoing aspects of the invention result in simple filter design (i.e. reduced order) relative to prior art tone detectors.

Abstract: Disclosed is an integrated tone detection processor for discriminating between tone and voice signals and determining the tones. The tone detection processor performs Automatic Gain Control (AGC) to normalize the power of the tone or voice signal. Further, the energy of the tone or voice signals are determined at specific frequencies utilizing a Goertzel Filter process. The tone detection processor determines whether or not a tone is present, and if a tone exists, determines the type of tone. Based upon determining the two maximum energy levels of the Goertzel filtered tone, whether the tone is a single tone, dual tone, silence, or other (e.g. speech) can be discriminated. The tone can then be identified by a user-defined dictionary of tones. Based upon various ON and OFF cadence checks in combination with the use of TONE ON and TONE OFF counters, tones can be declared.

Abstract: A device for processing a frequency shift keying (FSK) signal including caller ID information that comprises an analog-to-digital converter (ADC) converting the FSK signal into a digital FSK signal, the FSK signal further comprising a first frequency component, a second frequency component including the caller ID information, and a third frequency component, a first filter attenuating the first and third frequency components of the digital FSK signal to provide a first signal, a second filter attenuating the second frequency component of the digital FSK signal to provide a second signal, and a circuit calculating an energy level for each of the first and second signals, and selecting the first signal for output if the energy level of the first signal is smaller than that of the second signal, and selecting the digital FSK signal for output if the energy level of the first signal is greater than that of the second signal.

Abstract: A push-button signal receiving circuit and a push-button signal detection method are provided which can enhance frequency detection accuracy and yet can reduce erroneous determination as to the valid length of PB signal and thus erroneous operation. Valid signal determining portion determines the validity of a received PB signal in accordance with the results of determination as to the coincidence of continuance times of identification signals extracted by first and second frequency detecting portion for performing frequency detection over a small number of periods, and the coincidence of the frequencies detected by the first and second frequency detecting portion with those detected by third and fourth frequency detecting portion over a large number of periods.

Abstract: A system and method for determining DTMF coefficients stores a plurality of reference templates, at least some of said reference templates representative of likelihood ratios. A plurality of LPC coefficients is received. The LPC coefficients are representative of an input signal. The system and method determines a plurality of current likelihood ratios based, at least in part, upon the LPC coefficients. The system and method also determines an initial tone based, at least in part, on the minimum of the current likelihood ratios and the minimum of the reference likelihood ratios. A plurality of LSF coefficients is received. The LSF coefficients are determined, at least in part, upon the input signal. The system and method verifies the validity of the initial tone based, at least in part, upon the LSF coefficients.

Abstract: An off-hook management telecommunication system comprising a DTMF detector, an encoder and a microprocessor located within a channel unit. The system allows the user to depress a selected sequence of keys during a line connection which indicate to the microprocessor to hold the line off-hook, via signaling to a central office, despite the fact that the telephone is being returned to an on-hook position. The line is held off-hook for a predetermined amount of time to allow the user to switch telephones.

Abstract: A method of detecting frequency errors exceeding a predetermined limit in a sampled signal includes the step of determining a peak amplitude of the signal at a tone frequency for a first frame of samples of the sampled signals using a filter having a first amplitude versus frequency response. A peak amplitude of signal at the tone frequency is determined for a second frame of samples of the sampled signal using a filter having a second amplitude versus frequency response. A ratio between the peak amplitude of the first frame and the peak amplitude of the second frame is calculated and compared against a threshold to detect frequency errors exceeding the predetermined limit. Among other things, this method decouples the frequency error detection problem from the twist factor estimation problem.

Abstract: A system and method for generating Dual Tone Multi-Frequency (DTMF) tones in the media gateway of a Universal Mobile Telecommunications System (UMTS) network. The method includes receiving a DTMF signal in a media gateway controller, where the DTMF signal can be a stop tone request, or a start tone request, sending the DTMF signal from the media gateway controller to the media gateway, monitoring the status of a set of timers, where the set of timers includes a minimum tone duration timer, an inter tone timer, and a maximum tone duration timer, and responding to the received DTMF signal, said status of said timers, or a queued request. The system includes a media gateway, a plurality of timers within the media gateway, a media gateway controller, a finite state machine within the media gateway, where the finite state machine includes the following states: No Tone, Play Tone, Queue Stop Request, Inter Tone Timing, Queue Start Request, and Ready to Stop Tone.

Abstract: A telephone incoming signal discriminator includes a first relay, an FSK detector, a DTMF detector, a pin detector, a tone amplifier and oscillation control, an FSK/DTMF decoder IC, a memory, a buzzer, a comparison/setting control IC, an auto answer machine, and a second relay. When a telephone signal is received, it is detected by the FSK detector and the DTMF detector, decoded by the FSK/DTMF detector IC, and then compared with a set code by the comparison/setting control IC, so that the comparison/setting control IC drives the telephone to ring when matched, or switches on the second relay for enabling the incoming telephone signal to be shifted to the auto answer machine when not matched.

Abstract: Devices, software and methods are provided for encoding DTMF signals for telephone connections between digital voice communication systems that use compression, such as wireless connections or network connections. First the twist of the DTMF signals is determined, and then it is determined whether the twist is within a mapped range of a remote decoder. If not, the signal is first balanced to change the twist, and then the balanced signal is encoded.

Abstract: A communication apparatus connected to a PBX and an ATM network is provided with a DTMF signal detecting portion for detecting whether or not a DTMF signal is contained in a voice signal from the PBX, a DTMF signal monitoring portion, a DTMF cell generating portion for coding and sending out a DTMF signal, a DTMF cell decomposing portion for decoding a coded DTMF signal and a DTMF signal generating portion for generating a DTMF signal on the basis of the information content of a decoded DTMF signal and sending out this DTMF signal to the PBX, and the transmission side communication apparatus codes a DTMF signal in a specified form and transmits the DTMF signal and the reception side communication apparatus decodes the coded DTMF signal and, on the basis of this content information, restores the DTMF signal in a DTMF signal generating portion.

Abstract: A signal detector includes a transform unit and a post processing test unit. The transform unit is adapted to a transform unit adapted to receive at least first and second frames of input samples, determine a first plurality of energy values for the first frame based on a first set of transform coefficients, and determine a second plurality of energy values for the second frame based on a second set of transform coefficients. The post processing test unit is adapted to identify at least one target frequency based on the first plurality of energy values. The second set of transform coefficients is based on the target frequency, and the post processing unit is adapted to determine the presence of a first signal in the input samples based on the second plurality of energy values. A method for detecting a signal is provided. A first frame of input samples is received. A first set of transform coefficients is determined based on a first plurality of frequencies.

Abstract: A signal detector for detecting at least a first signal having a first frequency and a first minimum duration is provided. The signal detector includes a matched transform unit and an energy level detection unit. The matched transform unit is adapted to receive at least a first frame of time domain input samples at a sampling frequency and generate at least a first frequency energy value for the first frame based on at least a first subset of the time domain input samples. The first subset of the first frame has a width of less than about one half of the first minimum duration. The energy level threshold unit is adapted to compare the first frequency energy value to a threshold energy value to determine the presence of the first signal. A method for detecting at least a first signal having a first frequency and a first minimum duration is provided. The method includes receiving at least a first frame of time domain input samples at a sampling frequency.

Abstract: A frequency deviation detecting apparatus for detecting frequency deviation of a dual tone multiple frequency (DTMF) signal includes frequency deviation analyzers for analyzing a received signal for frequency components proximate fixed frequencies in analytical blocks, each analytical block having a length that ensures the precision required for detecting the frequency deviation. Each of the analytical blocks of the deviation analyzers partially overlays an adjacent block so that analysis by at least one analytical block is ensured within a minimum duration of a DTMF signal.

Abstract: A communication apparatus 1 or 2 connected to a PBX 4 or 5 and an ATM network 3, is provided with a DTMF signal detecting portion 102 for detecting whether or not a DTMF signal is contained in a voice signal from the PBX 4 or 5, a DTMF signal monitoring portion 103, a DTMF cell generating portion 105 for coding and sending out a DTMF signal, a DTMF cell decomposing portion 110 for decoding a coded DTMF signal and a DTMF signal generating portion 113 for generating a DTMF signal on the basis of the information content of a decoded DTMF signal and sending out this DTMF signal to the PBX 4 or 5, and the transmission side communication apparatus 1 or 2 codes a DTMF signal in a specified form and transmits the DTMF signal and the reception side communication apparatus 1 or 2 decodes the coded DTMF signal and, on the basis of this content information, restores the DTMF signal in a DTMF signal generating portion 113.

Abstract: A fast-converging, computationally simple, method for recognizing a single frequency tone or a sinusoid in a signal without prior knowledge of the tone frequency. The method employs a second order or higher auto-regressive model and includes: (a) sampling the signal at a constant sampling rate, and, for each sample, recursively determining a finite number of correlation coefficients using a time-reversed, exponentially weighted, future sliding equivalent of the signal, wherein the correlation coefficients are determined using pre-existing values of the correlation coefficients determined in a previous iteration, a current sample of the signal and at least two consecutively previous samples of the signal; (b) periodically determining at least the second auto-regressive coefficient modeling the signal using the correlation coefficients; and (c) recognizing the presence of the tone based on the value of the second auto-regressive coefficient.

Abstract: A method for detecting a tone signal includes determining a correlative value of an input signal obtained for each frame of a predetermined length, determining an estimating expression that represents an output power of a second order FIR band elimination filter that uses the correlative value of the input signal as an input and a frequency thereof as a parameter, determining a frequency at which a minimum value of the estimating expression is obtained, determining a prediction gain of the FIR band elimination filter at the determined frequency, and determining that the input signal is a tone signal if a value of the determined prediction gain exceeds a preset threshold value.

Abstract: A device for automatically identifying DTMF and FSK system is disclosed. A signal detector is provided for detecting signals on a telephone line. A DTMF and a FSK decoders are provided for decoding DTMF and FSK signals, respectively. A microprocessor is activated when the signal detector detects a signal on the telephone line for only activating the DTMF decoder to calculate frequency spectrum of the detected signal. When the calculated frequency spectrum conforms to DTMF frequency spectrum, it is determined that a DTMF system is in use. When the calculated frequency spectrum only has a frequency of about 1,200 Hz or 1,300 Hz, it is determined that a FSK system is in use, so as to deactivate the DTMF decoder and activate the FSK decoder.

Abstract: A multifrequency detector, such as a DTMF detector, includes a Goertzel module detecting energies of a current frame of an incoming signal at nominal tone frequencies. A number of ratios are computed from the detected energies and supplied as an input to a multidimensional thresholding device such as a neural network. The neural network generates a decision level to be used in a subsequent frame decision. A frequency estimation module also receives the incoming signal and generates a number of frequency estimation indications to be used in the final determination of whether the incoming signal contains a valid multifrequency signal. A low-level decision module returns a frame decision result (D/N) for the current frame based on inputs from the Goertzel module and the decision level. A high-level decision module receives the frame decision result and information based on the frequency estimation indications.

Abstract: Apparatus and methods for adaptively, reliably, and accurately measuring the duration of an alerting or other signaling tone. A tone detector in accordance with the principles of the present invention accurately measures a duration of a tone burst (i.e., tone pulse) using a long frame length DFT and a short frame length DFT. Based on information obtained by the short frame length DFT, the long (i.e., standard) frame length DFT may be interrupted and reset to begin a new frame of data synchronized with the start of the next short frame corresponding to the processing by the short frame length DFT to minimize noise in the processing by the long frame length DFT and to greatly improve the resolution of the measurement of the duration of a particular tone to correspond to the lengths of the short frames used by the short frame length DFT.

Abstract: An arithmetic processing section is designed to repeatedly execute product-sum arithmetic processing a number of times equal to the number of samples corresponding to each of the frequencies, in which a value obtained by subtracting a product-sum arithmetic value two sampling periods before from an input signal and a value obtained by multiplying a product-sum arithmetic value one sampling period before by a coefficient corresponding to a reference frequency contained in a DTMF signal are added. A comparator extracts an output value equal to or larger than a predetermined threshold value from the product-sum arithmetic values obtained by the arithmetic processing section. A matrix section determines the type of DTMF signal on the basis of at least two output values extracted by the comparator.

Abstract: A method and system for improved detection of analog signals, where the analog signals may be composed of one or more analog frequencies. In the method and system, an analog signal is received. A stream of data samples is created from the analog signal. Based on the stream of data samples, a confidence factor regarding the presence of the one or more analog signals is created. The confidence factor is created based upon a confidence factor calculated for each of the one or more analog frequency signals. The confidence factor calculated for each of the one or more analog frequency signals is calculated utilizing incremental energies associated with each of the one or more analog frequency signals.

Abstract: Computationally efficient DTMF detection methods and apparatus are presented that meet all of the ITU recommendations using the modified non-uniform DFT. The system of the present invention employs a high band filter block and two low band filter blocks to detect power at the 8 DTMF tones. The frame length of the high band filter blocks is one half the length of the low band filter blocks. The frame lengths are chosen to meet the ITU frequency selectivity requirements for all DTMF frequencies. The frames of the two low band filter blocks are staggered to produce outputs alternately, and are aligned with respect to the frame of the high band filter block to produce low band filter block outputs that coincided with the high band filter block outputs without the need for signal buffering. A system of power level tests are employed in conjunction with a system of timing tests to ensure that all ITU timing and frequency constraints are met.

Abstract: A system and method for DTMF tone detection receives an input signal. The input signal includes a DTMF tone. The DTMF tone has a first frequency and a second frequency. An initial first frequency and an initial second frequency of said DTMF tone are selected by calculating a plurality of cost functions. The initial first frequency is confirmed to be the first frequency and the initial second frequency is confirmed to be the second frequency using re-computed values of the plurality of cost functions.

Abstract: A signal detector includes a transform unit, a gain control unit, and an energy level threshold unit. The transform unit is adapted to receive a plurality of input samples and calculate a first plurality of delay values based on the input samples. Each delay value is based on at least one previous delay value and a current input sample. The transform unit is adapted to calculate a first energy value based on at least a subset of the first plurality of delay values. The gain control unit is adapted to determine if a selected delay value of the first plurality of delay values exceeds a predetermined threshold and scale the selected delay value, the at least one previous delay value used to calculate the selected delay value, and subsequent input samples received after the current input sample by a first amount in response to the selected delay value exceeding the predetermined threshold.

Abstract: A method and system for facilitating the detection of DTMF tones is disclosed. The method is based on detecting two tones using a modified nonuniform discrete Fourier transform that includes a phase correction term for each DTMF tone and harmonic. The disclosed method is employed by a DTMF detector that includes a sampling module, a computation module, an analysis module, and a decode module. The sampling module samples an input signal from a communication network at a rate sufficient to avoid data loss. The sample signal is then placed through a modified DFT which is more precise than filters or analog devices, particularly those utilizing a Goertzel algorithm. The computation module implements a fast recursive algorithm for completing the necessary computations. The analysis module checks for the present of energy level peaks at the DTMF tones and their harmonics. Once a DTMF signal is verified to contain a DTMF tone, the decode module transmits the,number, letter, or symbol to an interface.

Abstract: A signal detector for detecting at least a first signal having a first frequency includes a matched transform unit and an energy level threshold unit. The matched transform unit is adapted to receive at least a first frame of time domain input samples at a sampling frequency and generate at least a first frequency energy value for the first frame based on at least a first subset of the time domain input samples and a first matched filter coefficient. The sampling frequency is a non-integral multiple of the first frequency, and the first matched filter coefficient depends on the first frequency. The energy level threshold unit is adapted to compare the first frequency energy value to a threshold energy value to determine the presence of the first signal. A method for detecting at least a first signal having a first frequency is provided. The method includes receiving at least a first frame of time domain input samples at a sampling frequency.

Abstract: Performing tone detection by (1) creating a search engine for every period of all possible tones, (2) applying the search engines on one period of the unknown tone, (3) eliminating the search engines that did not match the period of the unknown tone, (4) reapplying the remaining search engines, and (5) repeating (3) and (4) until the unknown tone can be identified as one of the possible tones based on the remaining search engines.

Abstract: A voice encoding device according to the present invention includes an encoder having a first quantizing block suitable for voice encoding and a second quantizing block suitable for non-voice encoding and compressively encoding input signals, a voice/non-voice signal identification unit for identifying whether an signal input to the encoder is a voice signal or a non-voice signal and outputting a determination result, and a multiplexer portion for multiplexing respective outputs from the first quantizing block and the second quantizing block in order to output to a transmission path. In this case, the encoder has a selector for selecting either one of the first quantizing block or the second quantizing in accordance with the determination result from the voice/non-voice signal identification unit, and the first quantizing block and the second quantizing block compressively encode signals by using a same quantization table.

Abstract: A method of transmitting DTMF signals over a compressed computer network (24) comprises sending a packet containing a compressed DTMF signal followed by a confirmation packet. The confirmation packet preferably comprises an uncompressed DTMF signal which is transmitted on the same logical channel as the packets that represent voice signals. To detect the DTMF signal transmitted, a telephony Internet server (28) decompresses packets as they are received. If a packet appears to contain a compressed DTMF signal, the telephony Internet server looks for the presence of the confirmation packet before processing the previously received packet as a DTMF signal. In an alternative embodiment, the confirmation packet comprises a code that represents a DTMF signal. The packets that represent the voice signal and the code representing the DTMF signal are sent on separate virtual channels of the same logical channel.

Abstract: In a telecommunication system having a network switch capable of independently controlling inbound and outbound call legs, a system for, and method of, redirecting in-band control of signaling pertaining to a call placed by a calling party and a system for providing automatic call completion from the calling party to a called party. The control redirecting system includes: (1) call control circuitry, associated with the network switch, for routing the call from the calling party to another party through the network switch, the call thereby having an inbound leg from the calling party to the network switch and an outbound leg from the network switch to the other party and (2) call control redirection circuitry for treating the outbound leg of the call as a second inbound leg from the other party to the network switch and monitoring in-band control signals received from the other party via the second inbound leg.

Abstract: An interactive remote auction bidding system for conducting an auction among participants located at remote locations from the auction site utilizes a data input device for communication over a network to the auction site. The system includes a data processor located at the auction site for generating bid information for communication over the network to the remote locations. A processor located at the auction side monitors the participants' data input devices for sensing participant bids generated by the participants' data input devices. The system further displays visual bid information at the auction site for transmission over the network to the participants and generates audible bid information in support of that visual bid information.

Abstract: A remote telemetry system utilizing dual communication pathways comprising low-cost remote communications devices operating on existing wire-based communications systems, wireless communications systems, and/or a combination thereof, to provide real-time reading and control of the remote telemetry units. A central controller directs the operation of the remote telemetry units and receives data from the remote telemetry units. The central controller is configured to utilize a conventional broadcast communications channel to transmit commands to individual remote telemetry units, each of which is assigned a unique identification code. Signals broadcast from the central controller are received at receivers associated with each remote telemetry unit, which performs a directed operation if a unique identification code included in the broadcast signal matches the identification code assigned to the remote telemetry unit.

Abstract: Detection of alerting or other tone signals in a composite signal are reliably detected with an improved false tone detect suppression technique which employs the use of a moving window analysis on a subset of frequencies detected within an underlying speech signal performed during each of a plurality of data frames. The composite signal is transformed during each data frame using a discrete Fourier transform comprising the so-called Goertzel Algorithm. All of the Goertzels relating to the tone detection are analyzed during each data frame, but only a subset of the Goertzels relating to the sweeping harmonic analysis of the underlying speech signal are analyzed during any particular data frame.

Abstract: Computationally efficient DTMF detection methods and apparatus are presented that meet all of the ITU recommendations using the modified non-uniform DFT. The system of the present invention employs a high band filter block and two low band filter blocks to detect power at the 8 DTMF tones. The frame length of the high band filter blocks is one half the length of the low band filter blocks. The frame lengths are chosen to meet the ITU frequency selectivity requirements for all DTMF frequencies. The frames of the two low band filter blocks are staggered to produce outputs alternately, and are aligned with respect to the frame of the high band filter block to produce low band filter block outputs that coincided with the high band filter block outputs without the need for signal buffering. A system of power level tests are employed in conjunction with a system of timing tests to ensure that all ITU timing and frequency constraints are met.

Abstract: A generic translator (10) is provided for processing service requests sent by a digit collection client (16). Requests include billing validation (11), call routing (19), call screening (17), account code validation (15) or other services. These requests are processed by the generic translator (10) and successful results are sent back to the digit collection client (16) or a trunk selection process (20). The generic translator (10) can access an external entity (18) to assist in digit translation (13).

Abstract: A method of transmitting DTMF signals over a compressed computer network (24) comprises sending a packet containing a compressed DTMF signal followed by a confirmation packet. The confirmation packet preferably comprises an uncompressed DTMF signal which is transmitted on the same logical channel as the packets that represent voice signals. To detect the DTMF signal transmitted, a telephony Internet server (28) decompresses packets as they are received. If a packet appears to contain a compressed DTMF signal, the telephony Internet server looks for the presence of the confirmation packet before processing the previously received packet as a DTMF signal. In an alternative embodiment, the confirmation packet comprises a code that represents a DTMF signal. The packets that represent the voice signal and the code representing the DTMF signal are sent on separate virtual channels of the same logical channel.

Abstract: A communications device is presented including a DTMF detector for detecting a DTMF signal. When the DTMF signal is a Mode 2 Caller ID CAS, the first DTMF tone has a frequency of about 2130 Hz, and the second DTMF tone has a frequency of approximately 2750 Hz. An input signal includes signal energy within a first portion of the input signal frequency range which includes the first DTMF tone, signal energy within a second portion of the input signal frequency range which includes the second DTMF tone, and signal energy within a third portion of the input signal frequency range which excludes the first and second DTMF tones. The DTMF signal detector includes a first and second tone detection units, an extraneous signal detection unit, and detection logic. The first and second tone detection units receive the input signal and produce an output signal dependent upon the signal energy within the respective first and second portions of the input signal frequency range.

Abstract: A Caller ID service handling apparatus capable of upgrading and coping flexibly with change of service contents and addition of service. This apparatus has a program memory region in its memory so as to be flexibly applied to the service contents. The communication format of the exchange equipment and this apparatus is determined. The exchange equipment transmits a program corresponding to change or addition of service contents. This apparatus downloads necessary data. Thus, without requiring exclusive apparatuses individually, in spite of service contents differing corresponding to change in Caller ID service content, addition of new Caller ID service, or difference in service contents among telephone companies (carriers), it presents an apparatus capable of upgrading.

Abstract: A transfer method of a push-button signal includes the steps of detecting a push-button signal created by an end user terminal during a state in which the end user terminal is connected to a remote service system by an exchange via a network, by using a push-button signal receiver, encoding the push-button signal detected by the push-button signal receiver to a produce a push-button transfer signal by using the push-button signal receiver, and transmitting the push-button transfer signal to the service system from the exchange to the service system via a signal line of the network.

Abstract: A method of generation and detection of acoustic signals carrying alpha-numeric data for reducing the effects of noise and thereby improving signal transmission without the need to boost the power of the signal. In accordance with one aspect of the invention, a special DTMF acoustic signal consisting of a combination of two frequencies will be generated for the representation of a particular alpha-numeric character that will be similar to the standard DTMF tone. The difference between the amplitudes of both frequencies varies during the time of generation of the DTMF tone in such a way that both signals will arrive at a final destination detector, i.e., an interactive voice response board, at least for a portion of the generation time, at a relatively similar amplitude, thereby substantially increasing the probabilities of being recognized as a DTMF signal.

Abstract: Apparatus and methods for adaptively, reliably, and accurately measuring the frequency of an alerting or other signaling tone. A tone detector measures the frequency of a tone (continuous or pulsed) with a high degree of accuracy (e.g., to within 1 part in 10,000). Two lower order or smaller DFTs measure the energy level in two separate but intersecting frequency ranges. A simple ratio is determined from the relative energy measured from discrete Fourier transforms relating to each of the two separate frequency ranges, and an actual measured frequency is determined.

Abstract: A method of facilitating telephony communications over a packet-switched network includes detecting signaling tones in an audio stream and blocking them from the stream in response to the detecting. After the blocking, the audio stream is sent over an undependable channel in the packet-switched network. The detected signaling tones can be sent over a dependable channel instead of the undependable audio channel.