Westinghouse Electric Corporation

Theodore H York

William R Verbanets, Jr

James V Faulkner, Jr

Leonard C Vercellotti

Waymon A Melvin, Jr

Scott J Weikel

Jerry M Kennon

Roger D Moates

Carl E Yates

In a communication and control system, an improved interface between a digital IC and its associated microcomputer is provided wherein a serial shift register in the digital IC is used to store the message bits of a received message and control of the shift register is transferred to the associated microcomputer as soon as the interface is set up so that data stored in the register is not overwritten by another received message. A busy signal is also supplied over one line of the interface only during periods when the digital IC is actually receiving or transmitting a message.

Digital IC-microcomputer interface

A transceiver is provided with a means for determining its own prescribed frequency upon the occurrence of an adverse transient condition, such as lightning, or upon initial installation after manufacture. Since it can safely be assumed that a transceiver's prescribe reception frequency is the same as its transmission frequency, the present invention measures the period of its transmission frequency in order to determine the frequency of its reception frequency. The exact frequency of incoming demodulated messages must be known in order for the transceiver's digital demodulator to properly demodulate the incoming signals. A high frequency signal, such as 1 mHz, is used to increment a pulse counter and the values of this pulse counter are stored upon the occurrence of two successive negative edges of the carrier signal. The present invention also provides means for directing its carrier signal to an input port of its microprocessor during power-up sequence in order for the period of the carrier signal to be easily measured.

Transceiver with auto frequency sense

A communication network digital message format is provided in which on message start signal has a logic '1' value for two bit intervals to provide improved noise immunity in transmission of a message over a network medium. The start signal is followed by a control bit one logic value of which designates a plurality of message bits as instruction bits to enable an interface to be set up between the network and a microcomputer, the other logic value of said control bit designating a plurality of message bits as data bits for the microcomputer after said interface has been established.

Digital message format for two-way communication and control network

A toroidal air-core transformer characterized by substrates extending radially outwardly. Each substrate includes windings extending from one end to the other with each winding having a solder pad for connection with corresponding pads on the next adjacent segments.

Segmented toroidal air-core transformer

A time diversity carrier signal sampler utilizes a shift register in conjunction with a timer and a plurality of phase samplers. The instantaneous logic level of each phase is measured on a time diversity basis in order to avoid the disadvantageous affects of noise pulses which can occur coincidently on all three phases. The resulting carrier signal data is then provided to a microprocessor for subsequent analysis and phase characteristic determinations. By judiciously selecting the sample and clock frequencies of the shift register, the sampling frequency for each phase and the time between sampling each of the phases can be preselected.

Apparatus and method for sampling multiple carrier signals

A dual threshold is used in a coherent phase shift keyed demodulator to distinguish situations in which an incoming carrier signal is expected from those open ended conditions when a receiver is active, but when an incoming signal is not imminently expected. The use of a lower threshold permits more rapid detection and demodulation of a valid carrier signal by utilizing a standard which is less strict to determine the presence of a valid carrier signal when an incoming carrier signal is expected.

Power line communication receiver with dual threshold signal

A coherent phase shift keyed demodulator provides demodulation of a baseband data message through the use of a reference vector signal generator which employs an intermediate reference vector generated from the phase of an incoming carrier signal which, under certain conditions, is reversed in phase prior to being combined with a previous value of the reference vector to generate an updated reference vector signal. The demodulator incorporates a polarity sampler, an image signal generator and a zero crossing detector associated with a phase angle vector generator. A summation vector generator receives a signal from the phase angle vector generator and, in turn, provides signals to a phase detector and a reference vector generator. The demodulator also includes apparatus to perform concurrent carrier detection and bit synchronization operations.

Coherent phase shift keyed demodulator for power line communication

A microprocessor-based coherent phase shift keyed demodulator determines the phase of an incoming carrier signal by analyzing zero-crossings of the carrier derived by polarity sampling of the carrier. The polarity samples are initiated by sample pulses produced in bursts, with each burst being triggered by a single microprocessor interrupt. The sample rate within a burst is an exact multiple of the microprocessor clock frequency and is on the order of the basic microprocessor instruction time.

Coherent phase shift keyed demodulator with improved sampling apparatus

A powerline carrier communications system includes a plurality of types of load management terminals, each of which has a unique address, and a combination field configuration and test terminal which can be plugged into the load management terminals. The combination terminal is coupled to the powerline through the connection to the load management terminal and generates a separate set of test commands for each type of load management terminal, which are transmitted over the powerline for execution by the connected load management terminal. Some types of load management terminals include an INITIALIZATION ENABLE line which, when activated by the connected combination terminal, commands the load management terminal to accept and store an address value received over the powerline as its new unique address.

Electric utility communication system with field installation terminal

A remote meter reading system includes a dial register encoder and a pulse encoder both coupled to the same rotary disc of our induction watthour meter. A first electronic data register stores the non-volatile dial register encoder output, and a second electronic data register stores a value consisting of an initial value set by the dial register encoder at start-up time continuously augmented by the output of the pulse encoder since start up. Comparison and selective readout of the two electronic data registers reduces erroneous meter reading outputs.

Dual mode meter reading apparatus

Each customer location is equipped with a remote terminal which contains a role code identifying the remote terminal as an end device and a plurality of address codes. A plurality of signal repeaters are each connected with certain of the remote terminals through a distribution network. Each signal repeater contains stored route and role codes as well as a unique address code allowing each signal repeater to be additionally addressed as an end device. A central station produces an outgoing communication signal intended for at least one end device. A communication link couples the central station to the power distribution network. The communication signal includes a route code identifying a signal path to the end device, a role code identifying the first device in the identified route, an address code and a message code. Upon receipt of the communication signal by a signal repeater which is not the intended end device, the received route and role codes are compared to the stored route and role codes. If there is a match, the signal repeater removes its role code from the communication signal, inserts the role code of the next device in the identified route and retransmits the signal. The signal is continually modified and retransmitted until the message code is received by the intended end device.

Growing community of inventors

Raleigh, NC, United States of America

Theodore H York