Apparatus and method for providing AC isolation while supplying DC power
Granted: February 13, 1996
Patent Number:
5491402
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…
Programming language structures for use in a network for communicating, sensing and controlling information
Granted: February 6, 1996
Patent Number:
5490276
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…
Powerline coupling network
Granted: January 16, 1996
Patent Number:
5485040
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…
Network and intelligent cell for providing sensing, bidirectional communications and control
Granted: December 12, 1995
Patent Number:
5475687
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…
Sigma-delta converter having a digital logic gate core
Granted: November 28, 1995
Patent Number:
5471209
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…
Apparatus and method for reducing errors in data caused by noise through use of blanking
Granted: October 31, 1995
Patent Number:
5463662
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…
Error correction in a spread spectrum transceiver
Granted: October 24, 1995
Patent Number:
5461629
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.
Method and apparatus for interfacing between a twisted pair and an intelligent cell
Granted: September 26, 1995
Patent Number:
5454008
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…
Set of irons with progressive weighting system
Granted: July 25, 1995
Patent Number:
5435559
A set of iron golf clubs, with each golf club comprising a shaft and a club head. Each club head comprises a sole, a rear surface and a ball-striking face having a center of percussion. Each club head further comprises a first weight provided adjacent the sole and a second weight provided on the rear surface, the second weight comprising at least two rails, with a first rail positioned between the center of percussion and the toe portion, and a second rail positioned between the center…
Power coupler for coupling power from a transmission line to a node thereon
Granted: June 13, 1995
Patent Number:
5424710
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…
Configuration device for use in a networked communication system
Granted: May 30, 1995
Patent Number:
5420572
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…
Transceiver for transmitting and receiving stair-stepped sinusoidal waveforms
Granted: April 18, 1995
Patent Number:
5408497
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…
Power line communication while avoiding determinable interference harmonics
Granted: April 4, 1995
Patent Number:
5404127
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…
Source power coupler
Granted: February 21, 1995
Patent Number:
5391932
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…
Adaptive data recovery for spread spectrum systems
Granted: December 27, 1994
Patent Number:
5377227
A method and means for for recovering data in a spread spectrum communications system. The present invention includes a method and means for providing a sync window time period. The sync window is set to encompass the correlation values which are generated one baud time from the previous recovered data bit. The present invention also determines the peak correlation value within the sync window and the location in time within the sync window that the peak correlation value occurs. The…
Transceiver providing selectable frequencies and spreading sequences
Granted: October 18, 1994
Patent Number:
5357541
A transceiver for transmitting and receiving digital data is disclosed. The transceiver employs direct sequence spread spectrum communications techniques for reducing interference among multiple users in a communications network environment. Each transceiver has a transmitter for locking a digital bit stream to a predetermined spread spectrum chip sequence and carrier signal. Frequency of the carrier signal and the chip sequence. Both the carrier signal, the chip sequence and the bit…
Reconstruction of signals using redundant channels
Granted: October 11, 1994
Patent Number:
5355114
In a power line communication apparatus, data is redundantly transmitted on a first and a second carrier where the carriers are separated by a predetermined number of Hz. In the receiver two channels are used, one for each of the carriers. The noise level in each channel is independently determined. A switching network is used to allow the selection of the channel with the lesser noise or if the noise is approximately equal in both channels, the signals in the channels are combined.
Method and apparatus for interfacing between a twisted pair and an intelligent cell
Granted: September 13, 1994
Patent Number:
5347549
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 (pulse), then an anti-code violation (pulse of opposite polarity) 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…
Method and apparatus for preventing unnecessary retransmission of messages in a networked messaging system
Granted: July 5, 1994
Patent Number:
5327426
An improved apparatus and method for routing of messages in a networked system wherein reduced unnecessary retransmission of messages across routers is achieved by examining the address of the source of messages to be forwarded and, if the source of the message is on the transmit side of the router, not retransmitting the message. Further, when messages are originated which do not include source subnet address information, a router receiving such a message will update the source subnet…
Multiaccess carrier sensing network communication protocol with priority messages
Granted: June 7, 1994
Patent Number:
5319641
An improved network for communication of message packets. The network of the present invention implements an improved collision avoidance, detection and backoff system for communication on a media between nodes. The apparatus calculates a time period P after detecting the media is idle using a formula F which is a function of a pseudo-random delay factor T. If the media remains idle during the time period P, the device may transmit a message. The apparatus further has the ability to…
