A system includes a modulator configured to generate a communication signal whose modulation represents coded information to be transmitted to a local management unit connected to a photovoltaic module. A local management unit is configured to receive a communication signal whose modulation represents coded information from an inverter or a transmitter. The local management unit is configured to receive a unique pairing sequence; pair to a first transmitter or inverter; and receive communications from the first transmitter or inverter. The local management unit is configured to ignore communications from a second transmitter or inverter that is not paired to the local management unit.

A communication device in a network may receive a stream of frames from the network, in which each frame includes one or more beacon packets. A communication protocol being used by the network may be identified by tracking a preselected field within a sequence of beacon packets, in which the preselected field varies in a first known manner for a first protocol and in a second known manner for a second protocol. The communication device may then join to the network using the identified communication protocol to transmit and receive data.

Aspects of the subject disclosure may include, for example, a device that facilitates transmitting electromagnetic waves along a surface of a physical transmission medium without requiring an electrical return path that facilitates delivery of electric energy to devices, and sensing a condition that is adverse to the electromagnetic waves propagating along the surface of the physical transmission medium. Other embodiments are disclosed.

In one embodiment, a first device (e.g., a host device or power distribution unit) stores identification information of the first device, and determines, over a power connection, when the first device is in powered connectivity with a second device (e.g., a power distribution unit or host device, respectively). The first device may then communicate, with the second device over the power connection, identification information of at least one of either the first or second device, where the communicated identification information is accessible to a third device (e.g., a server) via a data network due to the communicating over the power connection. In another embodiment, a server may determine, based on the identification information, a physical location of a power distribution unit, and may deduce, based on the physical location of the power distribution unit, that a host device is physically located at the physical location of the power distribution unit.

Activity sensing in the home has a variety of important applications, including healthcare, entertainment, home automation, energy monitoring and post-occupancy research studies. Many existing systems for detecting occupant activity require large numbers of sensors, invasive vision systems, or extensive installation procedures. Disclosed is an approach that uses a single plug-in sensor to detect a variety of electrical events throughout the home. This sensor detects the electrical noise on residential power tines created by the abrupt switching of electrical devices and the noise created by certain devices while in operation. Machine learning techniques are used to recognize electrically noisy events such as turning on or off a particular light switch, a television set, or an electric stove. The system has been tested to evaluate system performance over time and in different types of houses. Results indicate that various electrical events can be learned and classified with accuracies ranging from 85-90%.

A device includes an interface and Time Division Multiple Access (TDMA) Medium Access Control (MAC) circuitry coupled to the interface. The TDMA MAC circuitry detects a beacon in a frame having a defined frame duration and determines a frame compensation value based on a start time of the frame, a reference start time of the frame, and a number of elapsed frames. A current frame duration value is determined based on the frame compensation value and the defined frame duration.

In accordance with one or more embodiments, an access point includes a first communication interface having: a first coupler configured to receive, via a first transmission medium, first guided electromagnetic waves from a first waveguide system of a distributed antenna system, wherein the first guided electromagnetic waves propagate along the first transmission medium without requiring an electrical return path; and also a first receiver configured to receive first data from the first guided electromagnetic waves. A data switch is configured to select first selected portions of the first data for transmission to at least one communication device in proximity to the access point.

A grounds maintenance system comprising: a robot tractor comprising; a robot body; a drive system including one or more motorized drive wheels to propel the robot body; a control system coupled to the drive system, the control system configurable to store a mow plan that specifies a set of paths to be traversed for a grounds maintenance operation and control the drive system to autonomously traverse the set of paths to implement the mow plan; a battery system comprising one or more batteries housed in the robot body; and a low-profile mowing deck coupled to the robot body, the mowing deck adapted to tilt and lift relative to the robot body, wherein the control system is configured to control tilting and lifting of the mowing deck and cutting by the mowing deck.

In a method for an optimized transmission of data in a wired multi-carrier (multi-carrier modulationMCM) transmission system from a transmitter to one or more receivers via a transmission channel, only one specified supply power is provided for the transmitter, a transmitted signal for transmitting data has a plurality of subcarriers, and the data together with redundant information is distributed to the plurality of subcarriers in such a way that the receiver can dispense with some of the subcarriers in order to determine the data. The method includes a step of determining frequency-dependent access impedances of the wired transmission channel on the transmitter, and a step of adjusting the signal amplitude of the individual subcarriers on the basis of the measured frequency-dependent access impedances sand the limited supply power.

In accordance with one or more embodiments, an access point includes a first communication interface having: a first coupler configured to receive, via a first transmission medium, first guided electromagnetic waves from a first waveguide system of a distributed antenna system, wherein the first guided electromagnetic waves propagate along the first transmission medium without requiring an electrical return path; and also a first receiver configured to receive first data from the first guided electromagnetic waves. A data switch is configured to select first selected portions of the first data for transmission to at least one communication device in proximity to the access point.