Abstract: An interface file structure for allowing transfer of information between nodes in a network and a binding process for configuring nodes in the network. The interface offers an advantageous format designed to provide for minimal reading and writing of records while requiring minimal storage space per record. Further, an advantageous format for storing numeric information is disclosed in which information providing the number of buffers allocated and the size of such buffers is stored in a single nibble thus reducing required storage space.

Abstract: A method and apparatus for compensating for distortion in a spread spectrum communications system particularly useful where the spread spectrum is transmitted over a power line. The information carrying signal (ICS) is split into two sub-bands and the ICS in one sub-band (or a correlation value determined from the ICS in that sub-band) is delayed relative to the other sub-band. The ICS (or correlation values) from the two sub-bands are recombined after the delay and processed in an ordinary manner. The time delay is selected so as to compensate for the distortion. In one embodiment, the correlation peaks in each of the sub-bands are examined and the time delay is determined by, in effect, aligning the peaks in the two sub-bands in time so that when the two sub-bands are combined, a sharper correlation peak is obtained.

Abstract: In a communications system, an apparatus and method for detecting a valid signal from noise. An adaptive threshold is used to qualify a received signal. The adaptive threshold is set according to the number of false detects occurring within a given time interval. The number of false detects is initially determined by a quick qualification process. This initial number is subsequently adjusted by a more accurate qualification process. The transmitted signal is modulated with a particular pattern. Upon receiving the signal, it is demodulated to retrieve that pattern. The demodulated pattern is correlated against multiple reference patterns and combined to provide a measure of peak correlation that is independent of pattern phase. Furthermore, a tone detector is used to distinguish valid signals from interfering tones. Two different types of detection methods are performed in parallel. One is based on the energy of the received signal, whereas the other is based on the correlation of the received signal.

Abstract: A transceiver module for coupling between cells in a distributed intelligence network and a twisted pair line. The module receives power from the line and provides power to its respective cell. At the end of transmitting a packet, the transceiver transmits a code violation, then an anti-code violation to dissipate energy in the line. This is followed by clamping the line for the dead time between packets. N transceivers may be connected (without a cell) to form a repeater. The transceiver module may be used in a network having free topology; that is, an ideal transmission line, with terminators is not needed.

Abstract: A transmitting box is connected to a first electrical outlet in a building. The phase of the first electrical outlet is used as the reference phase. The transmitter box senses each of the zero-cross-overs of the reference phase and injects a data packet of the data carrier frequency at each zero-cross-over. A receiving box is connected to a second electrical outlet in the building. The second electrical outlet has an unknown phase which may be different from the reference phase. The receiver box receives each data packet and senses each phase zero-cross-over of the unknown phase. The receiver box uses the time between each reception of a data packet and each detection of an unknown phase zero-cross-over to determine the phase angle of the unknown phase relative to the reference phase.

Abstract: An apparatus and method for network node identification and network configuration. Prior to physical installation, a first node of a network is communicated with by a dedicated apparatus wherein the first node is requested to transmit a first unique identifier for the node to the apparatus. The apparatus then stores the first unique identifier received from the first node, and generates the first unique identifier on a medium (e.g. a label). This first unique identifier may be represented on the medium in a coded format. In one embodiment, the coded format is a code 39 bar code and the medium is an adhesive label. The labels obtained from querying the nodes prior to physical installation may be affixed to a floor plan of a networking system during installation, indicating each node's physical placement in that system. Each of the identifiers may then later be automatically read by an automated apparatus for network configuration. This apparatus (e.g.

Abstract: A method and apparatus for resolving connection conflicts in a network is provide. A network connection point on a node cannot be added to a first network connection when it already belongs to a second network connection. When a particular configuration would otherwise violate this rule, a network connection point on the node is established as an alias to the network connection point. The alias network connection point is added to the first network connection. A correlation is established between the alias network connection point and the network variable that is associated with the network connection point. If the network variable is an input network variable, then the value of the network variable is updated responsive to messages received on either the first or the second connection. If the network variable is an output network variable, then messages are sent over both the first and second connections when the network variable is updated.

Abstract: A source power coupler for coupling a power source to a first transmission line and a second transmission line. DC power from the power source is conducted by the source power coupler to the first and the second transmission lines while AC signals on the first and the second transmission lines are isolated from the power source by the source power coupler. The source power coupler is comprised of an operational amplifier having a non-inverting input and an inverting input. The gate of a transistor is coupled to an output of the operational amplifier. The transistor's drain is coupled to one of the transmission lines. And the transistor's source is coupled to the inverting input of the op-amp. Thereby, a control loop is formed, which provides an AC impedance between the power source and one of the transmission lines. A resistor is coupled between the source of the transistor and the power source, and a capacitor is coupled between the non-inverting input of the op-amp and the power source.

Abstract: An improved programming interface which provides for event scheduling, improved variable declarations allowing for configuration of declaration parameters, and improved handling of I/O objects. In modern day computing devices and especially in networks of such devices it is important to provide for event scheduling; known computing devices allow for event scheduling based on the occurrence of a predefined event. However, such a system present shortfalls in that flexibility is not provided to allow scheduling based on any arbitrary condition. Therefore, it is disclosed to provide a programming environment which allows for event scheduling where the event may be any arbitrary condition thus providing increased flexibility in event driven programs. In addition, programs which run on such computing devices typically declare one or more variables; such variables having one or more parameters associated therewith.

Abstract: An apparatus for reducing power line communication signal attenuation is disclosed. This apparatus provides for reduction of power line communication signal attenuation by balancing reactance between chosen circuit elements and the typical impedances found in a house, structure, or similar entity. The present invention uses a series resonant circuitry to couple the communication signal to the power line. The inductance in the series resonant circuitry is chosen to compensate for the de-tuning effect of the typical power line to which it's coupled in the communication system.

Abstract: A cell for use in a network which provides sensing, control and communications. Each cell, as part of its manufacturing process, includes a unique 48-bit identification number. A terminal on the cell enables the broadcast of this unique number onto the network during initialization of the network so that each cell can be identified. The input/output section of each cell communicates with the plurality of processors in the cell allowing one processor to interpret messages received from the network without interrupts of functions performed by other processors.

Abstract: A sigma-delta A/D converter having a digital logic gate core. The converter is comprised of a loop filter for shaping the converter's quantization noise spectrum. The loop filter is comprised of an unbuffered CMOS logic gate inverter which can be implemented by a gate array. A quantizer is coupled to the loop filter. A logic gate buffer is configured as a one-bit comparator, which is used to perform the quantization. This logic gate buffer can be one of the gates of a gate array. A sampler is coupled to the quantizer for sampling the quantized signal. This sampler can also be implemented by digital circuitry of a gate array. The signal from the sampler is fed into a decimator. The decimator outputs a digital signal representative of the amplitude of the analog signal.

Abstract: An apparatus for snubbing or blanking digital signals representing a band of signals that includes an encoded carrier signal transmitted over a power line. An average signal level is compared with the instantaneous signal level to develop a blanking circuit control signal. Additionally, snubbing occurs in the circuit which determines the average signal level to prevent noise from building-up the average signal level. A hold-off signal is used in this circuit to prevent the average signal level from being latched permanently low. A unique infinite impulse filter subtracts out the D.C. offset thereby improving the dynamic range of the blanking. Additionally, the average signal level is used by AGC logic to control the gain at the front end of the apparatus. The state and switching of the AGC is controlled to minimize errors.

Abstract: An improved transceiver for power line communication using a spread spectrum signal. The amount of correlation for each bit in a word is determined. If a parity error occurs, the state of the bit with the weakest correlation is changed.

Abstract: A transceiver module for coupling between cells in a distributed intelligence network and a twisted pair line. The module receives power from the line and provides power to its respective cell. At the end of transmitting a packet, the transceiver transmits a code violation, then an anti-code violation to dissipate energy in the line. This is followed by clamping the line for the dead time between packets. N transceivers may be connected (without a cell) to form a repeater. The transceiver module may be used in a network having free topology; that is, an ideal transmission line, with terminators is not needed.

Abstract: A node power isolator for connecting a node of a two conductor transmission line network such as a twisted pair line to the network so as to enable the DC powering of the node from the network itself without significantly diminishing the signal levels on the network or interfering with the node's ability to receive signals from or transmit signals on the network. Current flow through the power isolator is through a transistor coupled in series with each transmission line to node connection, with the base to emitter voltage of the transistor clamped to be substantially constant at the signaling frequencies of interest, either directly by a capacitor connected there across, another circuit having a capacitor connected between the base and the emitter of another transistor or both. Various embodiments are disclosed.

Abstract: An apparatus useful in the configuration of communication network. The present invention provides for improved apparatus and techniques for configuration of network nodes. In particular, what is described is a device which may be coupled with each node of a network. When coupled to a node, the device and node cooperate in allowing communication of information identifying the node and the node type to the device. The node identification and type information may then be utilized to reliably complete configuration of a network.

Abstract: A transceiver for transmitting and receiving digital data represented as stair-stepped sinusoidal waveforms over twisted pair lines interconnecting nodes of a network. The transmitter of the transceiver converts square waves into the stair stepped sinusoidal waveforms by utilizing a number of current sources for supplying differing amounts of current to a resistor coupled across the twisted pair lines. Shift registers control a set of switches which control the direction and the amount of current flowing through the resistor. Thereby, the output voltage across the resistor can be controlled to produce the stair-stepped sinusoidal waveform by clocking the digital signal to the shift registers. The receiver of the transceiver re-converts received stair-stepped sinusoidal waveforms back to their respective digital signals.

Abstract: A power line communication (PLC) apparatus wherein a carrier is derived to avoid determinable interference harmonics. In order to transmit data on a power line containing the television interference or other determinable interference harmonics, the present invention uses redundant carriers at a frequency between the television interference harmonics. In the preferred embodiment, the first carrier is positioned at 118 KHz and the redundant carrier is positioned at 133.7 KHz for the PLC apparatus designed for use in the United States. Other carrier frequencies are used for other countries in order to avoid interference harmonics at a slightly different frequency. The present invention includes a waveshaping and modulation circuit for generating the modulated data waveform for output over the power line. In the preferred embodiment, the waveshaping and modulation circuit includes a waveshape ROM for storing samples that represent the appearance of the carrier waveshape.

Abstract: A transistorized source power coupler for coupling a power source to a pair of transmission lines. DC power from the power source is conducted by the transistorized source power coupler to the transmission lines. Meanwhile, AC signals on the transmission lines are isolated from the power source by the source power coupler. Consequently, the same pair of transmission lines can be used to supply power to cells of a communications system while also conducting data signals between those cells with minimal effect to the power source.