Abstract:
Techniques for over the air (OTA) microcontroller flash memory updates using a wireless network are disclosed herein. A control node first transmits the microcontroller flash memory update to all devices that can receive the message. Each packet of the message is relayed through multiple communication levels until all devices receive the packet. This starts with communications from the control node to each device node that has a direct communication path to the control node, which are referred to herein as “first level” device nodes. The first level device nodes then relay each communication to each other device node that has a direct communication path to the first level device nodes, which are referred to herein as “second level” device nodes. This process is repeated at each level of the wireless network until each of the plurality of device nodes has received the microcontroller flash memory update.
Abstract:
A dynamic self-configuring system for collecting metering data comprises a collector meter. The collector meter scans for meters that are operable to directly communicate with the collector and registers such meters as level one meters. The collector transmits instructions to the level one meters to scan for meters that are operable to directly communicate with the level one meters. The collector registers meters that respond as level two meters.
Abstract:
The present invention is directed to a frequency hopping spread spectrum transceiver. The transceiver includes a microcontroller; a transmitter having a voltage controlled oscillator, a direct digital synthesizer, and a power amplifier; and a receiver having an amplifier, a mixer, an IF amplifier, a demodulator, and a data slicer. When transmitting, the transmitter communicates a preamble over a predetermined number of preamble channels, and thereafter communicate groups of data bytes that each comprise a subset of the data message over a predetermined sequence of data channels. When receiving, the receiver investigates the predetermined number of preamble channels to search for the preamble, each of the predetermined number of preamble channels being associated with a predetermined number of data channels in each sequence of data channels. A number of bytes that comprises each group of data bytes is determined in accordance with a number of channels in the sequence of data channels and the predetermined number of times each byte of the data message is to be transmitted.
Abstract:
A communications module that permits remote meter reading of a utility meter via a wireless modem that communicates using data packet networks along a communications system, such as ARDIS. The communications module is a microprocessor-based transmitter/receiver which receives data collection requests from a system server, initiates data collection from a utility meter, and reports the data back to a host computer system residing, for example, at a central office. Preferably, session-based communication using the meter protocol is implemented between the communications module and the meter, and packet switching is used between the communications server and the communications module through the network.
Abstract:
A system and method for improving the ability of an electronic meter to make measurements on signals to determine content of different frequencies, and harmonics of the fundamental frequency, of AC signals (voltages and currents). The line frequency is determined and compensated for prior to performing frequency-dependent parameter measurements or determining frequency-dependent parameters.
Abstract:
A method for measuring an AC current in a conductor in which a DC current also exists includes the steps of (A) obtaining a first AC current measurement; (B) obtaining a measure of a power factor, fundamental frequency component, and second harmonic component; and (C) adjusting the first AC current measurement in accordance with an error value to obtain a corrected current measurement. The error value is determined as a function of the power factor, fundamental frequency component, and second harmonic component.
Abstract:
An automatic meter reading system utilizes repeater technology to access hard to read meters within a fixed network structure. The components of the radio system that are needed for two-way communications are employed without adding significant cost to the meter. Using this approach, each meter in the network has the ability to repeat messages as required.
Abstract:
A mutual inductance differential current transducer employs a toroidal coil mounted coaxially and generally centrally of the length of an alternating current conductor wiht a conductive sheet therebetween surrounding the conductor and of substantially the same length and in insulated relationship from the conductor. The axial length of the coil is less than approximately one-third the length of the conductor, and the toroidal cross-section has a longer leg parallel to the axis of the conductor and a cross-sectional area eliminating the need for external capacitive and magnetic shielding. The coil is wound with an integer number of layers of the same number of turns per layer, the total number of turns being selected to produce a predetermined range of voltage levels of the analog voltage signal output of the coil, produced in response to and representative of the differential current flow through the conductor. The coil is wound utilizing only conventional toroidal coil winding controls with resultant winding defects in each layer producing corresponding abberations in the analog voltage signal output, the abberations of the respective such contributions for the corresponding, plural integer number of layers being substantially self-cancelling and thereby maintaining the substantially linear responsive character of the analog voltage signal output of the coil.