Abstract: A method and system for distinguishing valid DTMF signals from spurious DTMF noise includes detecting signals having a first signal component indicative of DTMF signals and having a second signal component having frequencies unrelated to DTMF frequencies. The second component is utilized in isolation from the DTMF frequencies of the first signal component. The analysis includes determining a signal level representative of the second signal component. If the signal level exceeds a predetermined threshold level, the first signal component is determined to be spurious noise. On the other hand, if the signal level is below the threshold level, the first signal component is passed to a DTMF-responsive system, such as a voicemail system or a voice response unit. Optionally, the operation includes requesting confirmation of the signal of interest, if the signal level of the second signal component falls within a range which includes the threshold level as its upper limit.

Abstract: In order to transmit variable length coded data blocks while reducing data loses caused by code errors, the control circuit 7 makes a group of a plurality of variable length coded data, a fixing length circuit 9 fixes the code length of each of the variable length coded data thus grouped so that the data blocks each have an average code length and then makes a group of the data blocks in that condition, a header outputting circuit 8 prepares a header including information on the grouped data blocks and a synchronization word, and a control circuit 7 controls a switch SWC so that the prepared header and the group of data blocks are output through an output terminal 2. On the decoding side, the data blocks are synchronized/decoded by obtaining the code length of the group of data blocks and the number of the data blocks with reference to the location of the synchronization word in the header and information on the data blocks.

Abstract: A method and device for managing the communication of high speed analog data across a communications line. If the communications line is not authorized for communication of high speed analog data, line conditioning applied (e.g., at a digital line unit or subscriber line interface circuit) to the communications line is varied. The line conditioning may include echo suppression and/or hybrid balancing. If the line conditioning unit is a digital signal processor, the line conditioning is varied by varying coefficients or line types. If the line conditioning unit is a circuit, the line conditioning is varied by varying a control signal to a selection element of the analog circuit.

Abstract: The transmission properties of an optical fiber are enhanced by cooling the fiber gradually to temperatures of at least -300.degree. Fahrenheit, maintaining the fiber at such reduced temperature for a time suitable to stabilize the transmission properties of the fiber, and then allowing the fiber gradually to return to normal room temperature. The heating of the fiber to restore it to room temperature in part is accomplished by transmitting through the fiber optical pulses of the frequency and repetition rate the fiber will experience in normal use.

Abstract: A data transmission method, data transmission system, and a transmitter and receiver are provided which can implement higher quality variable rate transmission by making a more positive rate decision. In a variable rate transmission method transmitting fixed time length frames, each including variable length transmitted data, a transmitting side transmits user data plus an error detecting code, and a receiving side, assuming the entire transmittable final bit positions of the frame data, carries out Viterbi decoding of the frame data to the final bit positions.

Abstract: A control channel is searched for call waiting in a mobile station where the power supply for a receiving circuit is turned off during a break time of receiving level measurements, wherein in a first control channel selection mode, all the control channels are divided into a plurality of groups, the receiving levels of the control channels are measured group by group intermittently and sequentially. The intermittent measurement of these groups are repeated until a control channel having a receiving level equal to or greater than a first predetermined value is detected. When a receiving level equal to or greater than the first predetermined value is detected, the receiving levels of all the control channels are measured in a second control channel selection mode.

Abstract: A system and method enabling a user to remotely access an electronic calendar using a telephone network is provided. The system includes the electronic calendar for storing a plurality of schedules and a scheduler for accessing the schedules as a function of input signals received over the telephone network. Each schedule contains future appointments and events for either daily, weekly or other data interval periods. The scheduler enables selective retrieval and display of the appointments and events for any selected time period. The system is coupled to interfaces allowing the schedule information to be transmitted as audio information, video information, or e-mail information. The scheduler can compare the schedules to one another to automatically generate common meeting times. The common meeting time can then be transmitted to the various attendees using e-mail, audible instructions or voice mail.

Abstract: A DS-CDMA transmission method capable of improving the accuracy of channel estimation using pilot symbols by eliminating cross-correlation between pilot symbols inserted into code channels in CDMA multiplexing carrying out fast signal transmission. In each frame assembler, the pilot symbols, which are used for channel estimation for coherent detection, are inserted into coded information data on code channels at fixed intervals, and then the data is modulated by the modulator. The modulated data symbols in each code channel from the modulator are spread by the spreading modulator, the pilot symbols are spread using a spreading code, whereas the information symbols are spread using different spreading codes assigned to respective code channels. The spread signals of the code channels are summed up by the adder to be transmitted.

Abstract: A method and system for automatically providing remote notification of a locally detected event includes receiving data and analyzing the content of the data using a data filter of a computer. The data filter is configured to detect an indication of a predetermined event within the data. If the event is detected, the data filter activates a local event indicator associated with the computer. An event indicator monitor determines whether a user response is initiated within a configurable time interval after activation of the event indicator. If the monitor determines that no user response is initiated within the configurable time interval, the monitor transmits an establish-connection message to a control program. The control program responds to the establish-connection message by accessing an event notification message from a database which indicates access numbers of the remote communication devices to which to transmit the event notification message.

Abstract: An apparatus and method are disclosed for connecting a headset alternately to a telephone line and an audio device. The apparatus includes an audio connector for connecting the apparatus to the audio device, a telephone connector for connecting the apparatus to the telephone line, and a headset connector for connecting the apparatus to the headset. The apparatus also includes a switching circuit connected to the audio, telephone and headset connectors. The switching circuit connects the telephone connector to the headset connector in response to sensing a voltage greater than a predetermined threshold on the telephone line. When the voltage sensed returns to a value less than the predetermined threshold value, the switching circuit reconnects the headset connector to the audio connector.

Abstract: A method and apparatus for preventing network rerouting when the overhead associated with the reroute operation could result in system resources being overwhelmed. The system monitors link congestion and CPU utilization that will be caused by rerouting. A comparator determines whether the amount of congestion and CPU utilization is beyond an acceptable predetermined threshold. A reroute control unit prevents rerouting if the amount of link congestion and CPU utilization exceeds the predetermined threshold.

Abstract: A method and system for exchanging electronic messages, such as email messages, include isolating personal computers and other client devices from the process of converting a message attachment from one file format to a second file format. File-format conversions are out-tasked to enhance file accessibility, free computer resources, and conserve a user's time. The access requirements of each attachment to electronic messages are compared to the capabilities of a target client device. If it is determined that a file-format conversion is required, the conversion operation is assigned to a server that supports the process of reformatting the attachments. In an email environment, the server is substantially equivalent to the conventional email server, but includes enhanced conversion capabilities. In one embodiment, the determination of whether an attachment is accessible without conversion occurs at the server level. In another embodiment, the determination is implemented at the client device level.

Abstract: Method for preventing a facsimile server from looping back on itself, the method including the steps of: (a) transmitting fax server identifier information during fax transmission setup; (b) analyzing the fax server identifier information to determine whether the fax server identifier information is the same as that of the fax server that is placing the call; and (c) if the fax server identifier information is the same, dropping the call, otherwise, continuing the call. In a preferred embodiment, the fax identifier information is transmitted in the NSF command of the facsimile communication protocol.

Abstract: When errors occur in a received code sequence, an error concealment routine part 130 is actuated and a correct code sequence is generated based on a code sequence received before the errors are detected. A decoding routine part 21' executes a decoding process based on this code sequence and updates the internal state based on the decoded result. Thereafter, when the code errors are recovered, an error recovery routine part 140 is actuated. The error recovery routine part 140 re-estimates a correct code sequence during a time period when the errors are detected, based on a code sequence received before the errors are detected and a code sequence received after no more errors are detected, and generates a second estimated code sequence. The decode process part 21' executes the decoding process based on an internal state information for retaining the second estimated code sequence in an internal state storage part 23', and updates the internal state information based on the decoded result.

Abstract: A transmitted signal is enciphered or concealed to thereby prevent interference, even when data indicative of the receiver terminal is made public because of the use of a common access channel. In the transmitter, in a random-number bit adder 6, a random-number .alpha. (digital signal) generated by a random-number generator 5 is inserted into a transmitting data signal DA generated by a transmitting data generator 1, and the resultant is outputted as a signal (DA, .alpha.). An encipherment processor 2 enciphers the signal (DA, .alpha.) and outputs it as a signal (DA, .alpha.)'. In the receiver, this signal (DA, .alpha.)' is deciphered into (DA, .alpha.), and the random-bits .varies. are removed from (DA, .alpha.) to restore the signal DA.

Abstract: A CDMA communication method capable of providing a multi-rate user with high quality transmission using a spreading sequence selected from sequences which consist of multilayer sequences arranged in a hierarchical tree structure. A higher level sequence C.sub.16 (1) and its inverted sequence C.sub.16 (1) are included in its lower level sequences {C.sub.32 (1), C.sub.32 (2)} and {C.sub.64 (1), C.sub.64 (2), C.sub.64 (3), C.sub.64 (4)}, for example, and a sequence from a higher level is selected to transmit a higher rate data: The C.sub.16 (1) is used to transmit data whose peak rate is twice the peak rate of the data transmitted using its lower level sequences {C.sub.32 (1), C.sub.32 (2)}, and four times (=2.sup.2) that of the data transmitted using the sequences {C.sub.64 (1), C.sub.64 (2), C.sub.64 (3), C.sub.64 (4)}. The C.sub.16 (l), however, cannot be selected if any one of its lower level sequences {C.sub.32 (1), C.sub.32 (2)} and {C.sub.64 (1), C.sub.64 (2), C.sub.64 (3), C.sub.

Abstract: A method for managing transmission lines within a communication system which enables the automatic restoration of network access for user lines. The communication system includes user lines interfaced with groups of transmission lines and each group of transmission lines includes dedicated transmission lines which are connected to the user lines, idle transmission lines and reserved transmission lines. The method makes a number of idle transmission lines among the groups of transmission lines available for coupling by user lines which have a dedicated transmission line in a group of transmission lines that fails. The method determines the minimum number of transmission lines to be reserved by a comparison of the numbers of certain types of transmission lines in the different groups.

Abstract: A method for enabling a plurality of Local Service Providers within a common Numbering Plan Area (NPA) to serve Subscribers of the plurality of Local Service Providers. The method includes the step of assigning to each Subscriber of a Local Service Provider within the common NPA a unique three digit code, hereinafter referred to as a SPA code. The service provider area (SPA) code is used by the telephone system in the same manner presently used for routing calls made when a calling Subscriber dials the NPA code of the called party. Here, however, the SPA code is not dialed by the calling Subscriber. The dialed directory number, NXX-XXXX, of a called Subscriber subscribed to a different Local Service Provider, is sent to a database. The database maintains a record of the relationships between the directory numbers of Subscribers and the SPA codes of the Subscribers. The database retrieves the SPA code associated with the dialed directory number presently serving the called Subscriber.

Abstract: A radio channel initial transmission scheme for a mobile communication system which is capable of reducing an unnecessary interference with respect to the other radio channels as well as an unnecessary consumption of a battery of a mobile station. In the present invention, this is realized by not carrying out a transmission of the unnecessary general information during an initial period of a radio channel set up. More specifically, only the constantly necessary information among radio channel transmission signals is initially transmitted from a transmitting side of the base station and the mobile station, at a time of setting up a radio channel between the base station and the mobile station, and then the constantly necessary information and the general information other than the constantly necessary information are subsequently transmitted from the transmitting side, after a receiving side of the base station and the mobile station becomes ready to receive the radio channel properly.