Tellabs Operations, Inc.

Trimble Navigation Limited

Tellabs Wireless, Inc.

Thingmagic, Inc.

John C Carrick

Ornan A Gerstel

Paul C Talmadge

Stuart D Brorson

Rajiv R Ramaswami

Mark I Oppenheimer

Roger P Holmstrom

Eric B Saint Georges

Chaoyu Yue

Robert E Snyder

Eric J Frankfort

Thierry Maison

Ronald A Haberkorn

Michael A Wolf

Eric B SaintGeorges

William T Ralston

Yael Gregory Maguire

Francis Honore

Robert R Herold

Apparatus and methods are described which are useful for determining a location characteristic between an RFID tag and an RFID tag reader or a second RFID tag. In various embodiments, signals backscattered from a singulated tag over a range of frequencies are evaluated for in-phase I and in-quadrature Q signal components. The I-Q data is processed to determine phase delay angles associated with each signal frequency. The phase delay data can be processed by a sum of squared errors method or Fourier transform method to determine a distance to the singulated tag. The methods can also be used to determine any of a location, a radial velocity, a directional velocity of the singulated tag, and proximity of the singulated tag to a second tag.

Methods and apparatuses for RFID tag range determination

Apparatus and methods are described which are useful for determining a distance between an RFID tag and an RFID tag reader. In various embodiments, signals backscattered from a singulated tag over a range of frequencies are evaluated for in-phase I and in-quadrature Q signal components. The I-Q data is processed to determine phase delay angles associated with each signal frequency. The phase delay data can be processed by a sum of squared errors method or Fourier transform method to determine a distance to the singulated tag. The methods can also be used to determine any of a location, a radial velocity, a directional velocity of the singulated tag, and proximity of the singulated tag to a second tag.

A system for power supply synchronization in an Radio Frequency Identification (RFID) reader is shown and described. In one embodiment, the system includes one or more switched mode power supply devices and a signal generator. Each of the switched mode power supply devices provides power to at least one component of the RFID reader. The signal generator transmits a synchronization signal of a controlling frequency to each of the one or more power supply devices. In one embodiment, the system includes a signal processing unit that is configured to reject one or more spectral components from the output of the RFID reader.

Systems and methods for power supply synchronization in radio frequency identification (RFID) readers

A communication network comprising first and second communication paths, and nodes coupled therethrough. Each node comprises first and second switches, each having a first terminal coupled to an end of a first communication path, and a second terminal coupled to an end of a second communication path. Third terminals of the first and second switches are coupled together through at least one third communication path. A Wavelength-Division-Multiplexed device of the node is coupled to an external communication node and a fourth terminal of each switch. A node controller responds to an applied input by controlling at least one switch to cause selective coupling of at least one of (a) first and second nodes together via at least one of the paths, and (b) the external communication node and at least one of the first and second nodes via at least one of the paths.

Shared optical ring protection in a multi-fiber ring

Methods and apparatus for managing an optical network using pilot tones are provided. One method includes selecting an optical path having a plurality of nodes from a database defining an expected optical network. A detected list of pilot tones associated with each node of the selected optical path is generated. An expected list of pilot tones associated with each node of the selected optical path is generated. The detected and expected lists are compared to identify any mismatched nodes.

Methods and apparatus for optical network management using pilot tones

A method and system provide for sensing multiple wavelengths simultaneously in a single wavelength sensing device. The system may have a plurality of laser signals and a plurality of identifiable modulation signals. A respective laser signal of the plurality of laser signals is combined with a respective identifiable modulation signal of the plurality of identifiable modulation signals so that each of the laser signals is identifiable. A combined optical signal is then formed from the modulated laser signals. A sensor has an input port that receives the combined optical signal. The sensor identifies, for each of the modulated laser signals, a respective laser signal via the identifiable modulation of the respective modulated laser signal.

Methods and apparatus for sensing multiple wavelengths simultaneously in a single wavelength sensing device

A pilot tone generator receives optical energy from an optical communication medium carrying a plurality of optical signals. Each optical signal carries data modulated at a unique wavelength and further modulated with a unique identification signal. The identification signal has an amplitude corresponding to an optical power of the associated optical signal. The pilot tone receiver detects each identification signal from the optical energy received and determines its corresponding amplitude. The pilot tone receiver calculates the optical power of each optical signal in the optical energy in response to the amplitude of the associated identification signal.

System and method for measuring power of optical signals carried over a fiber optic link

Methods and apparatus for managing an optical network using pilot tones are provided. One method includes generating a list of pilot tones contributed by a selected node to each of its target nodes. Network pilot tone sources are re-configured so that a pilot tone source of any optical path incorporating one of the target nodes has a value distinct from the listed pilot tones. The selected node can then be added to the network. Another method includes generating a list including all selected network nodes to be incorporated into a new optical path and nodes adjacent to the selected network nodes. Network pilot tone sources are re-configured until a pilot tone source associated with the new optical path has a pilot tone distinct from that of any listed node. The new optical path can then be added to the network.

Methods and apparatus for maintaining a pre-determined ratio of a pilot tone power and a total mean optical power of an optical signal are provided. One apparatus includes an optical source coupled to provide an optical signal in response to a DC bias and an AC bias corresponding to a pilot tone signal. A processor is coupled to compute each of an AC component and a DC component of the optical signal from the same digitally sampled signal. A feedback control is coupled to vary at least one of the DC bias and the AC bias in accordance with a difference between a pre-determined value and a ratio of the AC and DC components.

Method and apparatus for maintaining a pre-determined ratio of a pilot tone power and a mean optical output power of an optical signal

Methods and apparatus for managing static and dynamic optical network configurations to enable mapping an actual optical network or validating an expected optical network are provided. In one embodiment a validation method includes the step of selecting an optical path having a plurality of nodes from a database defining an expected optical network. A list of detected pilot tones from each node associated with the selected optical path is generated. An expected list of pilot tones associated with each node of the selected optical path is generated. Comparison of the expected and detected lists identifies any mismatched nodes. Another method includes the step of setting a first pilot tone source to have a first pilot tone value. All other network pilot tone sources are set to have another pilot tone value. An optical path associated with the first pilot tone source is then mapped by identifying each node of the network having the first pilot tone value. Extraneous information can be applied to provide greater assurances as to likelihood of possible actual optical paths during the mapping process. Methods of re-configuring network pilot tone sources to preserve mapping and validation abilities when adding nodes, adding optical paths, or even adding another network to a pre-existing network are also provided.

A laser driver outputs a data protocol signal as controlled by an extinction control signal. The data protocol signal has a header including first and second bit patterns. A laser outputs an optical signal in response to being excited by the data protocol signal. The first and second bit patterns are measured and used to calculate an extinction ratio. The calculated extinction ratio is compared with a desired extinction ratio to generate the extinction control signal.

Extinction ratio calculation and control of a laser

Methods and apparatus related to maintaining a pre-determined ratio of a pilot tone power and a total mean optical power of an optical signal are provided. One method includes the steps of detecting the AC and DC components of an optical signal having a pilot tone signal. An amplitude of the pilot tone signal is varied in accordance with a difference between a pre-determined value and a ratio of the AC and DC components. Another method includes the step of generating an optical signal in accordance with a DC bias and an AC bias corresponding to a pilot tone signal. The AC and DC components of the optical signal are detected. At least one of the DC bias and the AC bias is varied in accordance with a difference between a pre-determined value and a ratio of the AC and DC components. An apparatus includes an optical source providing an optical signal in response to a DC bias and an AC bias corresponding to a pilot tone signal. The apparatus includes detectors coupled to measure the AC and DC components of the optical signal. A feedback control varies at least one of the DC bias and the AC bias in accordance with a difference between a pre-determined value and a ratio of the AC and DC components. In various embodiments, the DC bias only, the AC bias only, or both the AC bias and the DC bias are varied.

A wideband band bus in a base station of a wireless communication system includes consecutively interconnected slots and may be automatically configured into one or more sections that perform application specific cell processing operations, without requiring hardware or software changes to the base station. A section of the wideband bus includes a group of the consecutively connected slots containing digital signal processing modules which implement a cell processing application. The modules included in the slots of a section and the interconnections among the slots provide for diversity reception, expandable cell capacity and cell operations in accordance with wireless communication protocol standards.

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Wakefield, MA, United States of America

John C Carrick