AT&T Labs Research — Leading Invention, Driving Innovation

A system and method are disclosed for transporting deterministic traffic in a gigabit passive optical network. A system that incorporates teachings of the present disclosure may include, for example, an Optical Line Termination (OLT) for exchanging data traffic in a Gigabit Passive Optical Network (GPON) having a controller programmed to generate a timeslot schedule for transport of a desired bandwidth of constant bit rate (CBR) data traffic by selecting one or more timeslots from periodic frame clusters operating according to a GPON Transmission Convergence (GTC) protocol. Additional embodiments are disclosed.

A method and system for location determination and guidance using radio frequency identification (RFID) are disclosed. A location of a mobile RFID reader can be determined by detecting stationary RFID tags located at fixed locations. Each RFID tag stores location information associated with its position as well as location information of at least one other RFID tag. The location information stored by each RFID tag can be used to direct a user from one RFID tag to another. Thus, RFID technology is also used to guide mobile RFID reader between the fixed locations of the stationary RFID tags.

A method and system for tracking variable conditions using radio frequency identification (RFID) are disclosed. In embodiments of the present invention, an RFID sensor tag is used to measure a condition. The condition can be any measurable condition such as location, temperature, humidity, pressure, time, date, inertial measurements, etc. Variable data representing the measured condition is read from the RFID sensor tag in order to track the measured condition. The variable data can be read from RFID sensor tags in addition to reading tag identification data from RFID tags, so that the variable data can be associated with tag identification data.

Certain exemplary embodiments provide a method, comprising: automatically detecting at an agent an installation of a communications device to a local network coupled to the agent; automatically offering via the communications device a plurality of user-selectable service options relating to a service provider's network and relating to at least one capability of the communications device, the at least one capability detected by the agent; in response to a selection of at least one service option from the plurality of service options, providing via the agent a user connection address.

A wireless subscriber terminal (ST) for use with IP push-to-talk (PP2T) service using a wireless local area network (WLAN) operating in a plurality of modes, including a mobile terminal having an ability to communicate over the air to a wireless Access Point (AP), the mobile terminal further programmable to use conventional WLAN protocols, and a method for operating the wireless terminal are described.

The specification describes a new architecture for RFID systems that is adapted to process large numbers of RFID tags and provide information about a large number of items. The system provides for multiple tag readers. The tag readers are active and have both transmit and receive capability. The system includes a gateway tag that receives information about individual items from the multiple readers and thus contains data on the entire inventory of items. This allows each of the multiple readers to conveniently access data for the entire inventory of items.

A secondary Ethernet-like wireless communication system overlapped by a dominant Ethernet-like wireless communication system, and including radio access and communication for activation, association, and authentication of a wireless device in the secondary Ethernet-like wireless communication system. An automated private service activation (APSA) port is used for accepting access and communication requests of a wireless device seeking activation, association and authentication in the secondary Ethernet-like wireless communication system. The APSA port provides an access and communication channel for radiating signals at a level exceeding a signal level of the access and communication channel only within limited spatial constraints. In addition the APSA port provides space for receiving the wireless device for activation and communication in the secondary Ethernet-like wireless communication system.

A premises, connected to receive broadband service(s) and also connected to a cable system, is provided with a broadband interface which connects to in-premises cabling which is coupled to consumer receivers such as a television sets, PDAs, laptops. Connected to the broadband interface is an adjunct device which channels broadband, data and voice signals supplied to an in-premises wireless system as distinguished from the signals supplied to the cable connected consumer receivers. The adjunct device formats the broadband and voice signals or any broadband service into packet format suitable for signal radiation and couples them to the in-premises coax cabling, via a diplexer, at a first selected location. At a second cable location a second diplexer, connected to the cable, separates the broadband, data and voice signals and couples them to a signal radiation device (i.e., an RF antenna or leaky coaxial cable) which radiates the signal to the immediate surrounding location. Various devices, near to the second cable location for specific services, receive the wireless signals (i.e., broadband, data and voice) from the radiating antenna.

A wireless subscriber terminal (ST) for use with IP push-to-talk (IPP2T) service using a wireless local area network (WLAN) operating in a plurality of modes, including a mobile terminal having an ability to communicate over the air to a wireless Access Point (AP), the mobile terminal further programmable to use conventional WLAN protocols, and a method for operating the wireless terminal are described.

A premises, connected to receive broadband service(s) and also connected to a cable system, is provided with a broadband interface which connects to in-premises cabling which is coupled to consumer receivers such as a television sets, PDAs, laptops. Connected to the broadband interface is an adjunct device which channels broadband, data and voice signals supplied to an in-premises wireless system as distinguished from the signals supplied to the cable connected consumer receivers. The adjunct device formats the broadband and voice signals or any broadband service into packet format suitable for signal radiation and couples them to the in-premises coax cabling, via a diplexer, at a first selected location. At a second cable location a second diplexer, connected to the cable, separates the broadband, data and voice signals and couples them to a signal radiation device (i.e., an RF antenna or leaky coaxial cable) which radiates the signal to the immediate surrounding location. Various devices, near to the second cable location for specific services, receive the wireless signals (i.e., broadband, data and voice) from the radiating antenna.

A method and system for tracking variable conditions using radio frequency identification (RFID) are disclosed. In embodiments of the present invention, an RFID sensor tag is used to measure a condition. The condition can be any measurable condition such as location, temperature, humidity, pressure, time, date, inertial measurements, etc. Variable data representing the measured condition is read from the RFID sensor tag in order to track the measured condition. The variable data can be read from RFID sensor tags in addition to reading tag identification data from RFID tags, so that the variable data can be associated with tag identification data.

The present invention is a system for increasing Signal-to-Noise Ratio (SNR) in a wireless communication system comprising a plurality of antennas each antenna providing a signal, a device for selecting a subset of signals provided by the plurality of antennas, a maximum ratio combiner for summing the selected subset of signals provided by the plurality of antennas, and a decision device for measuring the selected subset of signals against a predefined threshold. The device for selecting the subset of signals is coupled to the plurality of antennas. The maximum ratio combiner is coupled to the selected subset of signals and the decision device for measuring the selected subset of signals against a predefined threshold. The decision device is coupled to the selecting device such that one selected signal of the selected subset of signals is replaced by an unused signal provided by the plurality of antennas.

A premises, connected to receive broadband service(s) and also connected to a cable system, is provided with a broadband interface which connects to in-premises cabling which is coupled to consumer receivers such as a television sets, PDAs, laptops. Connected to the broadband interface is an adjunct device which channels broadband, data and voice signals supplied to an in-premises wireless system as distinguished from the signals supplied to the cable connected consumer receivers. The adjunct device formats the broadband and voice signals or any broadband service into packet format suitable for signal radiation and couples them to the in-premises coax cabling, via a diplexer, at a first selected location. At a second cable location a second diplexer, connected to the cable, separates the broadband, data and voice signals and couples them to a signal radiation device (i.e., an RF antenna or leaky coaxial cable) which radiates the signal to the immediate surrounding location. Various devices, near to the second cable location for specific services, receive the wireless signals (i.e., broadband, data and voice) from the radiating antenna.

An architecture is described for providing IP push-to-talk (IPP2T) service using a wireless local area network (WLAN) serving a plurality of subscriber terminals (STs), having at least one broadband access network terminal (BANT), the BANT coupled to and interacting with at least one of a plurality of Access Points (APs) via a local area network (LAN), the plurality of APs in communication with the plurality of subscriber terminals; a multicast-enabled network, the multicast-enabled network coupled to and interacting with at least one BANT via a broadband access network; an IP network coupled to, and interacting with, the multicast-enabled network via an edge router; and a WLAN mobile radio service (WLMRS) controller (WLMRSC) coupled to and interacting with the IP network via a multicast-enabled router (MR).

The present invention is a system for increasing Signal-to-Noise Ratio (SNR) in a wireless communication system comprising a plurality of antennas each antenna providing a signal, a device for selecting a subset of signals provided by the plurality of antennas, a maximum ratio combiner for summing the selected subset of signals provided by the plurality of antennas, and a decision device for measuring the selected subset of signals against a predefined threshold. The device for selecting the subset of signals is coupled to the plurality of antennas. The maximum ratio combiner is coupled to the selected subset of signals and the decision device for measuring the selected subset of signals against a predefined threshold. The decision device is coupled to the selecting device such that one selected signal of the selected subset of signals is replaced by an unused signal provided by the plurality of antennas.

Automatic activation of a wireless device with a first wireless communication system occurs within an area having an overlapping second wireless communication system. Operation of the first communication system access procedure is achieved by masking an access and authentication process for the second communication system from interference from the control signal levels of the second wireless communication system. During the first time access, the first communication system is supplied with the SID and MIN and ESN numbers for authentication and access.

A premises, connected to receive broadband service(s) and also connected to a cable system, is provided with a broadband interface which connects to in-premises cabling which is coupled to consumer receivers such as a television sets, PDAs, laptops. Connected to the broadband interface is an adjunct device which channels broadband, data and voice signals supplied to an in-premises wireless system as distinguished from the signals supplied to the cable connected consumer receivers. The adjunct device formats the broadband and voice signals or any broadband service into packet format suitable for signal radiation and couples them to the in-premises coax cabling, via a diplexer, at a first selected location. At a second cable location a second diplexer, connected to the cable, separates the broadband, data and voice signals and couples them to a signal radiation device (i.e., an RF antenna or leaky coaxial cable) which radiates the signal to the immediate surrounding location. Various devices, near to the second cable location for specific services, receive the wireless signals (i.e., broadband, data and voice) from the radiating antenna.

A subscriber loop test apparatus relates to the testing of a subscriber loop by the use of a touchtone telephone. The touchstone buttons on a telephone provide Dual-Tone, Multiple Frequencies for each key pressed. For example, referring to FIG. 1, pressing the `3` key causes tones at 697 and 1477 Hz to be sent across the telephone line. Pressing a sequence of keys provides discrete coverage of the frequency band from 697 to 1477 Hz, through the use of the touchtone telephone. The frequency band from 697 to 1477 Hz can be characterized in this fashion. Information about the line: loop loss (loop length), presence of bridge taps (i.e., excessively long bridge taps in particular) or loading coils, and the presence of Digital Loop Carriers (DLCs), et cetera. The use of the switch-hook flash provides the ability to determine the channel (impulse) response of the loop, including any noise and hum that may be on the loop due to imbalance or coupled interference.

Automatic activation (i.e., first time access) of digital wireless/cellular mobile telephones with a private/localized wireless/cellular system (i.e. a secondary system) occurs within an area having an overlapping macrocellular primary wireless communication system (i.e., a dominant system). Operation of the secondary access procedure is achieved by shielding/masking an access and authentication process for the secondary system from interference from the control signal levels of the dominant wireless communication system. During the first time access, the secondary system is supplied with the SID and MIN and ESN numbers for authentication and resultant access.

Broadband services are provided to customer premises, whose existing premise wiring does not have broadband capability, by disaggregating the various signals, including broadband services, supplied to the premise from a broadband communication link at the customer premise's edge, so that the existing POTS wires, within the customer premises, may function as separate channels for varied broadband and narrow band services. Intra premises broadband services are disaggregated so that POTS service responds normally to the network while internal LAN networks operate independently of the outside system network.

High efficiency and high power output are attained in a multi-tone FF RF amplifier by eliminating fundamentals in a first loop and then operating on the IMD products only in a second loop. Since lower power tones are adjusted in the IMD product reduction, less complex, lower power processing circuitry is required and higher efficiency is realized since both amplifiers add in-phase and approximately equally at the RF output.

Parallel combined redundancy and switched redundancy are provided for active RF devices (i.e., amplifiers) in a cable plant system with a switch/coupler circuit of passive magnetic devices and switches that respond to an amplifier failure by switching the circuit into a combined or switched redundancy mode as needed to maintain a suitable dynamic range of operation. In either redundancy mode, the switch/coupler circuit operates with a constant 3dB reduction of dynamic range.

A multi-tone signal amplifier topology and an amplifying method in which a first amplifier outputs a first signal having at least one fundamental frequency signal and a first distortion signal. A second amplifier outputs a second signal that has a fundamental frequency signal corresponding to each fundamental frequency signal of the first signal and a second distortion signal. Each fundamental frequency signal of the second signal is substantially in-phase with the corresponding fundamental frequency signal of the first signal, while the second distortion signal is substantially 180.degree. out-of-phase with the first distortion signal. An output coupler combines the first and second signals to form a third signal having the corresponding fundamental frequency signals of the first and second signals constructively combined and a third distortion signal that is a difference between the first distortion signal and the second distortion signal. A detector, coupled to the third signal, generates a control signal applied to the second amplifier for adjusting at least one of an amplitude and a phase of the second distortion signal thereby minimizing the third distortion signal. The second amplifier circuit includes an adjust circuit that varies at least one of an amplitude and a phase of the input signal for the second amplifier in response to the control signal.

An RF coupler incorporating a pair of branch circuits which combine first and second input signals supplied at the same impedance level, amplitude and phase into an output signal at the same impedance level, twice the amplitude and phase shifted with respect to the input signals when both input signals are present, and which, if only one of the input signals is present, passes that input signal through its branch circuit to the output without loss, while terminating the branch circuit associated with the absent input signal with an equal impedance.