Itron Gmbh

Interactive Technologies, Inc.

Eric W Lofstad

Brian Taylor Brunn

Brian Karl Seemann

John Bergman

John W MacConnell

Thomas Anthony Lee

Kurt Hasselfeldt

Normand T Lemay, Jr

Eric Sadowski

Laurent Maleysson

In one aspect, a phone-interface device determines whether a problem has occurred at a control panel by determining whether a signal from the control panel has been received, and when a signal has not been received within a period of time, the phone-interface device transmits an error message to a monitoring station. In another aspect, the control panel determines whether a problem has occurred at the phone-interface device by determining whether a signal from the phone-interface device has been received, and when a signal has not been received within a period of time, the control panel transmits an error message to a user. In another aspect, the phone-interface device contains memory to buffer data transferred between the control panel and a monitoring station. In this way, a high-speed connection between the phone-interface and the monitoring station can be accommodated while using a lower-speed connection between the phone-interface device and the control panel.

Wireless phone-interface device

A phone-interface device receives a wireless signal from a control panel. The wireless signal encodes information regarding a system condition that has occurred in a facility. The phone-interface device communicates the system condition to a monitoring station. The phone-interface device receives its electrical power from the telephone line or from an energy storage device. In another aspect, the phone-interface device receives a provisional-alarm signal command from a control panel. The phone-interface device determines whether a disarm command has been received from the control panel. When a disarm command has not been received before expiration of a period of time, the phone-interface devices sends an alarm condition to a monitoring station.

The present invention presents a closed loop system that utilizes a non-linear reference to control a power amplifier's output power in order to obtain a linear transfer function of dB per adjustment step of a reference input. The closed loop system demonstrates that each non-linear stage/step in an automatic gain control system can create a linear closed loop system when using a non-linear reference. The closed loop system of the present invention eliminates the need for a linearization circuit for the system's power detector. The closed loop system may be used with most power amplifiers when linear control in terms of dB vs. adjustment setting of the input reference signal is desired. Output power in terms of dBms can be accurately set in linear steps where power control over a wide dynamic range is desired.

Linear power control loop

A meter reading system preferably includes an external modem module (EMM), a hub and a data collection system. The EMM communicates with one or more utility meters and, as such, is preferably selected on the basis that it incorporates a communication format that is compatible with the communication format of the utility meter such that the utility meter does not require modification to be communicatively coupled to the EMM. The EMM obtains meter data from the utility meter and converts to a radio frequency communication format. The radio frequency formatted data is then transferred to the hub. The hub then translates the radio frequency data into an analog or digital telephone communication format, which is then transferred to the data collection system for use by the utility as desired, e.g. utility billing, tracking, control, etc. The data collection system need only recognize one communication format rather than attempting to accommodate numerous message formats such as wires, coaxial cable, optical fiber, or radio frequency.

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Eagan, MN, United States of America

Eric W Lofstad