Abstract: A security element formed on a substrate having a printing side and a viewing side is provided, the security element including: a first image portion provided on the printing side of the substrate, the first image portion including one or more micro-image elements; a second image portion provided on the printing side and/or the viewing side of the substrate; and a plurality of focussing elements disposed on or in the viewing side of the substrate for observing the one or more micro-image elements; wherein the first image portion and the second image portion are integrated into at least one distinguishable security element when observed from the viewing side of the substrate.

Abstract: A downhole tubular cutting system includes a cutter comprising an explosive material configured to cut a tubular. The system further includes a generator body coupled to the cutter on an end of the cutter such that the generator body will be oriented uphole or downhole of the cutter when the cutter is positioned with the tubular. A detonating cord or igniter fuse is disposed around the generator body.

Abstract: A downhole tubular cutting system includes a cutter comprising an explosive material configured to cut a tubular. The system further includes a generator body coupled to the cutter on an end of the cutter such that the generator body will be oriented uphole or downhole of the cutter when the cutter is positioned with the tubular. A detonating cord or igniter fuse is disposed around the generator body.

Abstract: A security element formed on a substrate having a printing side and a viewing side is provided, the security element including: a first image portion provided on the printing side of the substrate, the first image portion including one or more micro-image elements; a second image portion provided on the printing side and/or the viewing side of the substrate; and a plurality of focussing elements disposed on or in the viewing side of the substrate for observing the one or more micro-image elements; wherein the first image portion and the second image portion are integrated into at least one distinguishable security element when observed from the viewing side of the substrate.

Abstract: A system and a method for underground gasification comprising a downhole ignition device. The downhole ignition device may comprise a connection housing at a first end of the downhole ignition device. The connection housing may comprise an igniter and a first fire mix. The downhole ignition device may further comprise a body coupled to the connection housing. The body may comprise pyrotechnic modules arranged in series and additional first fire mix. A cap may be disposed at a second end of the connection housing. Additionally, the downhole ignition device may comprise a supply line and a recovery system. A method for igniting an underground energy source may comprise positioning a downhole ignition device adjacent an underground energy source in a wellbore, igniting a first fire mix in the downhole ignition device, and igniting a series of pyrotechnic modules arranged in the downhole ignition device.

Abstract: A method of measuring a defect level of a region of a substrate for a security document, wherein the defect level is associated with reduced transparency of the region of the substrate, the method including the steps of: digitally imaging the region to create a digital image, the digital image containing light intensity data; and analysing the digital image including: calculating a statistical measure of the light intensity data in the region; and assigning a defect score to the region based on the statistical measure of the light intensity data in the region.

Abstract: A system and a method for underground gasification comprising a downhole ignition device. The downhole ignition device may comprise a connection housing at a first end of the downhole ignition device. The connection housing may comprise an igniter and a first fire mix. The downhole ignition device may further comprise a body coupled to the connection housing. The body may comprise pyrotechnic modules arranged in series and additional first fire mix. A cap may be disposed at a second end of the connection housing. Additionally, the downhole ignition device may comprise a supply line and a recovery system. A method for igniting an underground energy source may comprise positioning a downhole ignition device adjacent an underground energy source in a wellbore, igniting a first fire mix in the downhole ignition device, and igniting a series of pyrotechnic modules arranged in the downhole ignition device.

Abstract: A pouch for enclosing a case containing a collectible item is provided, in which the case contains a label along an edge of the case. The pouch includes a window formed on the pouch and positioned such that the label is visible through the window when the case is enclosed within the pouch. A plurality of pouches containing cases may be stored adjacent one another, with the labels being visible through the windows.

Abstract: A system and method for providing audio and visual access to images of an item stored within a protective case includes a code, address, or other indicator directing a user to a location where images of the stored item can be found. The code may include a URL for a particular website or a bar code, QR code, or other scannable or accessible code to direct a user to the location having the images. In some versions, the stored images of the protected item may amount to a digital “tour” of the stored item.

Abstract: A method (500) for estimating at least one offset in a subcarrier that is subject to distortion in a multicarrier communication system. The method comprises receiving a plurality of subcarriers wherein the plurality of subcarriers contain the subcarrier that is subject to the distortion; and generating a plurality of first channel estimates for a respective plurality of received subcarriers that are not subject to the distortion. The method further comprises processing a number of the plurality of first channel estimates for the respective plurality of received subcarriers that are not subject to the distortion to generate a second channel estimate for the subcarrier that is subject to the distortion; and estimating an offset associated with the subcarrier that is subject to the distortion.

Abstract: A method (500) for estimating at least one offset in a subcarrier that is subject to distortion in a multicarrier communication system. The method comprises receiving a plurality of subcarriers wherein the plurality of subcarriers contain the subcarrier that is subject to the distortion; and generating a plurality of first channel estimates for a respective plurality of received subcarriers that are not subject to the distortion. The method further comprises processing a number of the plurality of first channel estimates for the respective plurality of received subcarriers that are not subject to the distortion to generate a second channel estimate for the subcarrier that is subject to the distortion; and estimating an offset associated with the subcarrier that is subject to the distortion.

Abstract: The present invention relates to estimating and correcting for frequency offset errors in wireless receivers, and is particularly but not exclusively related to MIMO WLAN applications. The present invention provides an improved method of tracking receiver frequency offsets in a receiver for MIMO systems. These receiver based frequency offset components are caused by errors or inaccuracies in various receiver sub-systems such as phase lock loops or carrier frequency oscillator error, and sampling clock rate errors. The frequency offsets due to each of a number of receiver sub-systems are estimated by monitoring frequency offsets on a number of channels or subcarriers (such as OFDM pilot channels) on different frequencies. These channel frequency offsets are preferably estimated by detecting the phase rotation between adjacent pilot symbols on each respective channel. They are then weighted according to a quality parameter of the estimates, which corresponds to their accuracy.

Abstract: A lattice reduction device is described for determining a reduced lattice for a MIMO decoder. The device comprises a data processing element operable to receive matrix information and to apply one or more data processing operations on the matrix information. The device further comprises first and second parallel operation means operable in conjunction with the data processing element so that any operation carried out by said data processing element on said matrix information is directly matched by an operation carried out on respective matrix information. The data processing element is operable, on an input triangular matrix being an R component of a QR decomposition of a channel state matrix, to tend non diagonal elements of said triangular matrix towards zero on the basis of matrix column operations and to make corresponding column operations at said first and second parallel operation means.

Abstract: Lattice reduction aided MIMO detection is disclosed for a packet based signal comprising a header and one or more data symbols. The detector comprises a pre-processing section operable to derive channel decoding information on the basis of a channel estimate from the header, storage means operable to store the channel decoding information, and a data processing section operable to process the one or more data symbols with reference to the stored channel decoding information.

Abstract: A communications system including a transmitting device having plural transmit antennas and a receiving device having plural receive antennas. When it is determined that an error has occurred in a first data transmission attempt in which data signals are transmitted from a first selection of transmit antennas for receipt at a second selection of receive antennas, a second data transmission attempt is performed in which the data signals are re-transmitted from a third selection of transmit antennas for receipt at a fourth selection of receive antennas. Before the second transmission attempt, a reconfiguration operation is performed to ensure the channel response between the transmit and receive antennas selected for the first transmission attempt is different to the channel response between the transmit and receive antennas selected for the second transmission attempt. Data is then recovered at the receiving device using information from the first and second transmission attempts.

Abstract: In a lattice-reduction-aided receiver based wireless communications system, outputs are determined on the basis of a received signal, the received signal being modulated onto a plurality of sub-carriers.

Abstract: In a lattice-reduction-aided receiver based wireless communications system, soft estimates of transmitted bit values are determined from a received signal by applying lattice reduction to the channel estimate and equalising the received signal in accordance with the reduced basis channel, and determining probabilities of transmitted bits having particular values. The method includes selecting an initial candidate vector in the reduced basis and determining further candidate vectors in the reduced basis dependently of the initial candidate vector, determining a corresponding transmitted symbol vector for each candidate vector and, on the basis of the received signal determining the probability of each transmitted bit value having been transmitted and log-likelihood ratios of transmitted bits.

Abstract: Roots on a plant cutting are formed by continuously circulating oxygenated water low in minerals and contaminates, a pH within a predetermined pH range, and a water temperature within a predetermined water temperature range about the severed end of the plant cutting.