Abstract: Systems, methods and computer products for establishing a mesh-network consisting of wireless personal area network (WPAN) having a large number of nodes. Exemplary embodiments include a gradient-driven mesh-network establishment method, including switching on a plurality of nodes in a vicinity of the wireless personal area network, detecting an acknowledgment signal via a wireless personal area network signal, querying for at least one or a resource and a physical quantity, selecting a subset of the plurality of nodes and instructing the subset of the plurality of nodes to send out a low power radio transceiver DISCOVER squirt signal to a neighborhood associated with the subset of the plurality of nodes, wherein nodes exclusive of the subset of the plurality of nodes turn off in response to an expiration of a time-out period.

Abstract: A method for tracking a plurality of containers each joined to an electronic tracking device having routing capabilities and a WPAN-enabled radio receiver/transmitter configured to attempt to connect to a pre-configured WPAN upon being activated comprises activating the radio receiver/transmitter of each tracking device joined to a container being loaded onto a cargo vessel; receiving an indication from each tracking device that fails to connect to the WPAN; intermittently performing a network scan to locate each WPAN-connected tracking device; intermittently configuring the WPAN to include each WPAN-connected tracking device in a hybrid tree-mesh network topology; intermittently configuring routing information stored on each WPAN-connected tracking device to maintain mutual communication with each WPAN-connected tracking device and enable mutual communication between each WPAN-connected tracking device; receiving transport-related data from each WPAN-connected tracking device; transmitting the transport-rela

Abstract: A method for tracking a plurality of containers each joined to an electronic tracking device having routing capabilities and a WPAN-enabled radio receiver/transmitter configured to attempt to connect to a pre-configured WPAN upon being activated comprises activating the radio receiver/transmitter of each tracking device joined to a container being loaded onto a cargo vessel; receiving an indication from each tracking device that fails to connect to the WPAN; intermittently performing a network scan to locate each WPAN-connected tracking device; intermittently configuring the WPAN to include each WPAN-connected tracking device in a hybrid tree-mesh network topology; intermittently configuring routing information stored on each WPAN-connected tracking device to maintain mutual communication with each WPAN-connected tracking device and enable mutual communication between each WPAN-connected tracking device; receiving transport-related data from each WPAN-connected tracking device; transmitting the transport-rela

Abstract: Systems, methods and computer products for establishing a mesh-network consisting of wireless personal area network (WPAN) having a large number of nodes. Exemplary embodiments include a gradient-driven mesh-network establishment method, including switching on a plurality of nodes in a vicinity of the wireless personal area network, detecting an acknowledgment signal via a wireless personal area network signal, querying for at least one or a resource and a physical quantity, selecting a subset of the plurality of nodes and instructing the subset of the plurality of nodes to send out a low power radio transceiver DISCOVER squirt signal to a neighborhood associated with the subset of the plurality of nodes, wherein nodes exclusive of the subset of the plurality of nodes turn off in response to an expiration of a time-out period.

Abstract: A WPAN system for establishing communication between a control station of a cargo vessel and a plurality of containers that are loaded onto the vessel is provided that comprises a base station configured to establish and manage a pre-configured WPAN having a hybrid tree-mesh network topology and a plurality of electronic tracking devices each being provided with a WPAN-enabled radio receiver/transmitter and routing capabilities. The base station is configured to communicate with the control station through a local area network on the vessel. Each tracking device is configured to be joined to a respective container of the plurality of containers and to connect to the WPAN upon being activated.

Abstract: A method and apparatus are provided for maximum-likelihood data detection in a partial-response (PR) data channel including a head and disk assembly providing an analog signal coupled to an analog to digital converter (ADC) providing digital samples. A plurality of digital samples are received from the ADC. The received digital samples are applied to a selected first filter and a selected second filter. The first filtered digital samples are applied to a first data detector, and the second filtered digital samples are applied to a second data detector. A predetermined parameter is identified, and at least one of the first and second data detectors is selected responsive to the identified predetermined parameter.

Abstract: In recording systems using partial-response maximum-likelihood detection (PRML) techniques, data sequences are preceded by a preamble consisting of all ones. Coding schemes are disclosed which allow to keep the number of consecutive ones occurring in the coded data sequences at a minimum, while simultaneously restricting the number of consecutive zeros in full and partial data sequences to a low value which is important for improving receiver operation. The disclosed coding schemes and apparatus enable a faster and more reliable discrimination between timing preambles and data sequences, thus allowing to use shorter timing preambles which results in faster receiver start-up and in a reduction of storage overhead for the preambles.

Abstract: A method and apparatus are provided for controlling a digital filter function included in a data path within gain and timing control loops of a PRML magnetic recording channel. The digital filter function is removed from the data path during an acquisition mode and the digital filter function is restored to the data path during a tracking mode. A predetermined gain and a quantized delay at a synchronization frequency are provided when switching from acquisition mode to tracking mode. A unity gain and a delay of an integer number of sample periods are provided at a synchronization frequency when switching from acquisition mode to tracking mode.

Abstract: The channel characteristics of magnetic-disk storage devices vary with track radius. An adaptive three-tap transversal equalizer that compensates these variations for systems using partial-response signaling is presented. The equalizer coefficients are updated by applying a procedure that is related to the recursive least-squares algorithm. This new updating procedure does not require multiplications and is well suited for high-speed implementation. Results obtained by computer simulations and measurements with a prototype have shown that the proposed adaptive equalizer can effectively compensate variations in magnetic-disk channel characteristics with track radius.

Abstract: An apparatus and a method for fast acquisition of the sample-timing phase in systems using partial-response signalling are disclosed. For fast initial adjustment of the timing phase, a known preamble is transmitted. During that phase, previous schemes could occasionally hang up for an extended period of time at the unstable equilibrium point halfway between the desired sampling times. The new procedure eliminates the hangup problem by introducing a hysteresis effect which greatly diminishes the probability of reversals in the once chosen direction of timing-phase adjustment. Thus, reliable adjustment of the timing phase with a much shorter preamble is achieved. The apparatus for furnishing a timing correction signal .DELTA..tau..sub.n includes a timing gradient generator portion (41) and a data sample reconstruction portion (43). The data sample reconstruction portion (43) develops a present reconstructed data sample x.sub.n from the present received signal sample y.sub.

Abstract: A maximum-likelihood sequence decoder is used with a partial-response signaling system for processing sequences of sampled values from a communication channel or recording device. The partial-response signals can be duobinary, dicode, or partial-response class-IV. The maximum-likelihood decoding for each sequence can be based upon a two-state trellis. Instead of two survivor metrics for two states, only a difference metric is necessary.

Abstract: A maximum-likelihood sequence decoder is used with a partial-response signaling system for processing sequences of sampled values from a communication channel or recording device. The partial-response signals can be duobinary, dicode, or partial-response class-IV. The maximum-likelihood decoding for each sequence can be based upon a two-state trellis. Instead of two survivor metrics for two states, only a difference metric is necessary.