Abstract: A method and system, for use in a communication system in which data is transmitted in data frames of a predetermined time duration, for the positioning of the data within the data frames for transmission. A computation circuit computes according to the deterministic code a pseudorandom position for the data within each data frame. A positioning circuit positions the data within each data frame in the computed position.

Abstract: A data communication system comprises a main device with a first microcomputer and an operating device with a second microcomputer. The devices are connected to each other by a first wire and by a second wire. In addition to that, input interrupt terminals of both devices are connected to the second wire. One device starts the sending of data by pulling the second wire to a first level, the detection of this by the other device is signalled back via the first wire and both devices then start an internal timer. When a predetermined time, corresponding to a data item to be sent, has lapsed the sending device pulls the second line again to the first level. This is detected by the other device, which measures the lapsed time and which uses this time to determine the data item sent by consulting preset conversion rules, that give a relation between time and a data element.

Abstract: Mobile stations randomly set delay amounts for each message to be sent, on the basis of the timing of a symbol received from a base station, and delay transmission signals for time intervals corresponding to the delay amounts. The base station 11 despreads signals received from the mobile stations to extract basic symbol timing for each mobile station and, at the thus extracted timing, takes each despread output into the corresponding demodulator for demodulation.

Abstract: A method and system, for use in a communication system in which data is transmitted in data frames of a predetermined time duration, for the positioning of the data within the data frames for transmission. A computation circuit computes according to the deterministic code a pseudorandom position for the data within each data frame. A positioning circuit positions the data within each data frame in the computed position.

Abstract: A time-division multiplex communication transmission apparatus includes a logic processing circuit, a digital filter, a modulation circuit, and a high-frequency amplification unit. The logic processing circuit performs logic processing of input burst data and outputs a burst timing signal for each time slot for time-division transmission. The digital filter converts output data from the logic processing circuit into baseband data for modulation. The digital filter is reset at a time slot boundary when no burst data signal is present in an adjacent time slot. The modulation circuit modulates an output signal from the digital filter. The high-frequency amplification unit performs burst waveform processing of an output signal from the modulation circuit on the basis of a burst timing signal from the logic processing circuit.

Abstract: A monolithic digital chirp synthesizer (DCS) chip using GaAs/AlGaAs HI.sup.2 L technology. The 6500 HBT gate DCS chip is capable of producing linear frequency modulated (chirp) waveforms or single frequency waveforms. The major components of the DCS are two pipelined accumulators, a sine ROM, a cosine ROM and two digital to analog converters.