Abstract: A method of encoding a transmission signal to reduce multiple access interference at a receiver. A data source signal including a plurality of source symbols is received into a transmitter. The source symbols are encoded using low energy encoding forming encoded codewords. An identifying pattern is applied to the encoded codewords forming a transmission signal. In one embodiment, the identifying pattern is a unique pseudo-random pattern identifying the data source. Once the pattern has been added, multiple transmission signals can be summed together and then modulated onto a carrier wave. The transmission signals are then transmitted on the carrier wave which is at a pre-selected frequency. The low energy encoding format is such that a sequence of signals forming codewords is created. Each sequence of signals is characterized by an energy and normally a high bit consumes energy whereas a low bit requires substantially less energy.

Abstract: A method and apparatus in a radio communication system (100, 101) provides simulcast control channels for a coverage area (500), and message channels transmitted in coverage zones (502) within the coverage area (500) on a time-division multiplex basis (FIG. 4). A first modulation technique generates (814, 816, 818) each of the message channels at a first average output power substantially less than a peak output power of a transmitter (202). A second modulation technique generates (806, 808, 810) each of the control channels at a second average output power approximately equal to the peak output power of the transmitter (202), thereby increasing usable coverage distance from the transmitter (202) for the control channel compared to the message channel. The control channels are allocated (FIG. 5) to the coverage zones (502) in a staggered geographic pattern such that reception of the control channels is maintained substantially throughout the coverage area (500).

Abstract: A method of regulating backpressure traffic in a packet switched network made up of a plurality of switching elements each having a local buffer memory identifies at least one switching element which succeeds at least one other switching element in a transmission path. The at least one succeeding switching element has a congested local buffer memory. A backpressure signal is transmitted to the at least one other switching element. Packets destined for the succeeding switching element are queued in the local buffer memory of the at least one other switching element. Next, it is determined when the occupancy of the local buffer memory for the other switching element has exceeded a predetermined threshold. In response to the exceeded predetermined threshold, the other switching element ignores the backpressure signal transmitted from the succeeding switching element and transmits the queued packets to the succeeding switching element.

Abstract: Dual detection paths containing speed recognition devices automatically determine the rate at which data is being transmitted on a multi-rate digital data communications network such as a token ring network. The multiple detection paths operate simultaneously with each detection path provided with a Phase Lock Loop (PLL) and a pattern recognition device. The PLL and its associated pattern recognition device are made to operate at one of the known ring speeds. The ring speed is determined by the detection path which is able to recognize a predetermined data pattern from the network.