A half-duplex digitally-controlled telephone communication apparatus for permitting half-duplex communication between local and remote subscribers. Analog speech of one subscriber to be transmitted to the other subscriber is converted to a digital format, processed by real-time speech processing apparatus, stored in a delay buffer, and processed in modem apparatus for transmission to the other subscriber. In accordance with the present invention, the delay buffer provides a delay of a sufficient duration to compensate for inherent delays in the system in detecting the presence (or absence) of speech signals and serves to prevent the loss to the remote subscriber of portions of speech of the local subscriber, especially the onset of speech or rapid utterances of the local subscriber. The apparatus of the invention further includes apparatus for preventing the transfer of the communication channel or line from the local subscriber to the remote subscriber during normal pauses in the speech of the local subscriber.
An electronic system and a method substantially eliminates any delays caused by buffering of a signal containing speech. The electronic system comprises a receiver for receiving signals, a buffer, coupled to the receiver, a buffer controller coupled to the buffer, and an audio section for presenting signals received to a listener. The method comprises the following steps. The receiver receives an input signal representing speech, and produces an output signal representing the input signal after a delay intentionally introduced in the system. The delay corresponds to the length of the buffer. The buffer stores the input signal in the buffer at an input rate, and produces the output signal at an output rate. The buffer controller determines whether the delay or buffer length is greater than a predetermined threshold, and analyzes at least a portion of the input signal stored in the buffer to determine which parts of the input signal may be removed without substantial deterioration of the signal quality according to at least one predetermined criterion, when the buffer length is greater than a predetermined length. The buffer controller then deletes at least some of the parts of the input signal stored in the buffer that comply with the predetermined criterion.
Half-duplex switched carrier operation is emulated in a full-duplex voiceband data transmission system by utilizing predetermined signal indications in each channel to signal the initiation and termination of user data in that channel and thus to control the Receive Line Signal lead extending to the terminals at respective ends of the transmission channel. The signal indication which signals the initiation of transmission is illustratively two scrambled spaces inserted into an idle-state sequence of continuous scrambled marks. The signal indication which signals the termination of transmission is illustratively a stream of 65 unscrambled marks.
An SMBus protocol is terminated at a personal computer and a remote-control connection control device for converting signals to data that can be received by each device inside a wired remote control is provided. The remote-control connection control device comprises an A/D converter and a register. After being stored in the register, data transmitted from a CPU as SDATA are outputted from SOUT as serial data and exercises direct control over both an LCD driver and a backlight. An analog signal inputted from the switch of the wired remote control is inputted to the remote-control connection control device as an AIN and after being converted into a digital value, the signal is read into the CPU as SDATA via an SMBus and the command is executed.
A transmission-reception apparatus wherein signals are bidirectionally and mutually transmitted and received between a transmitter and a receiver using a single transmission line, characterized in that the input and output portions of the transmitter and the receiver are respectively equipped with bidirectional line drivers and with flip-flops that are set by signals received through the line drivers, are reset by signals transmitted through the line drivers and change over the line drivers to signal transmission and reception. Said receiver is equipped with a counter for counting the number of signal receptions, a decoder for decoding the output of the counter and means for discriminating the reception signals by means of the output of the decoder.
A voice data transmission system and method which can reduce transmission delay time and can remove unnatural conversation in a received voice signal due to the truncation of a head part of the voice signal. The signal transmission side of the voice data transmission system, when a voice detection signal is generated, continuously transmits, at a transmission rate faster than a usual transmission rate, a first voice data block at the time of generation of the voice detection signal as well as voice data blocks which are followed by the first voice data block and which correspond to a time duration from the generation time of the voice detection signal block to a predetermined time. In a voice detection mode, the data transmission side subjects voice data to a block formation operation and, after the block formation is completed, transmits the voice data block. The signal reception side of the data transmission system, when receiving a voice packet signal followed by the continuation of a predetermined time of silence, estimates a fluctuation absorbing delay time for the voice packet signal on the basis of transmission delay times between packets corresponding to its head part, and attaches packets corresponding in number to the estimated fluctuation absorbing delay time to the head part of the received voice packet signal.
