Abstract: The invention relates to a system and method of recording data on an optical disc by a plurality of laser beams positioned along inner tracks to outer tracks of said optical disc, said optical disc comprising segments each being identified by a start of segment, said method comprising the steps of: switching writing on (710) successively each laser beam at different starts of segments for recording data, switching writing off (720) successively each laser beam arriving at the start of a segment previously recorded by another laser beam, detecting (730) when only one laser beam remains writing on, detecting (740) a subsequent start of a segment accessed by said one laser beam, switching writing off (750) said one laser beam, shifting (760) all the laser beams so that the innermost laser beam gets positioned at said subsequent start.

Abstract: An optical disc apparatus capable of conducting seek processing stably. If an angle is given to an objective lens in a radial direction by using an actuator at the time of seek processing, then it is possible to correct deviation between an amplitude center of a tracking error signal obtained when crossing a track and a level obtained when a tracking servo system is in the on-state, which is caused by an objective lens getting out of a center of intensity distribution of laser light. The deviation can also be improved by adding an offset to the tracking error signal. Therefore, stable seek processing is conducted by conducting tilt correction or adding an offset to the tracking error signal, according to a movement condition.

Abstract: In a tracking control method for use in an optical disk drive to read/write an optical disk, an open-loop tracking control operation of the optical disk drive is first performed according to an input tracking error signal and a predetermined periodical offset to generate a dynamic offset. Afterwards, a closed-loop tracking control operation of the optical disk drive is performed according to the input tracking error signal calibrated with the dynamic offset.

Abstract: A multi-layered information recording medium including a plurality of recording layers, the multi-layered information recording medium comprising: a user data area for recording user data; and a plurality of spare areas including at least one replacement region, wherein when the user data area includes at least one defect region, the at least one replacement region may be used in place of the at least one defect region, wherein a first spare area of the plurality of spare areas is positioned so as to be contiguous to a first user data area of a first recording layer, a second spare area of the plurality of spare areas is positioned so as to be contiguous to a second user data area of a second recording layer, and the first spare area and the second spare area are positioned approximately at the same radial position on the multi-layered information recording medium.

Abstract: A clock generation method detects from servo signals a degree of decentering of a patterned medium having recording pits arranged in a circular pattern and changes a clock frequency for recording/reproduction based on the detected degree of decentering.

Abstract: The present invention relates to an optical reader/writer for a two dimensional storage disc, comprising means (21, 22, 23, 14, 16, 15) for generating a plurality of laser beams and projecting said beams onto a rotating disc, means (24, 25, 26) for detecting the beams after being diffracted by the disc, and means (24, 27, 28) for determining a focus error signal (29) based on one of said plurality of beams. The plurality of beams comprises an array of beams having a first wavelength, and a dedicated focus tracking beam having a second wavelength, and the focus error signal (29) is based on said focus tracking beam. According to the invention, beams having one wavelength is used for the actual accessing of the data on the disc, while a beam having a second wavelength is used for focus tracking. The focus tracking can then be based on one single beam without interference from adjacent beams.

Abstract: In conventional one-dimensional optical storage systems, the data is arranged in a linear fashion, and the format is read out by a single spot. A two-dimensional encoded disc is different, because the data is arranged in a two-dimensional manner (bits are on a bit lattice) and the data is read out by multiple spots. It is important to know the relative intensity of the read-out spots, because the intersymbol interference is used in the signal processing of the reflected signals, and the present invention provides a way of calibrating the relative intensities by placing one or more mirror sections (150) in a non user-data area of an optical record carrier (1) and using the signals reflected therefrom to determine the relative intensities and enable the required accurate calibration of the relative intensities. In one exemplary embodiment, a mirror section (15) is located in the lead-in area (2) of the record carrier (1) in addition to a plurality of broad meta-tracks containing calibration patterns (152).

Abstract: An optical disk drive sets optimum recording power responsive to recording linear speed. When data are recorded in an optical disk, data are managed for each recording unit block (RUB). An APC area is provided at the top of RUBs, and OPC is performed by use of the APC area, whereby optimum recording power responsive to recording linear speed is set. Tentative optimum recording power responsive to recording linear speed is set, and test data are written, for a try, in the APC area at recording power that is determined by increasing or decreasing the tentative optimum recording power by a trace amount. The optimum recording power is set in according with a ? value obtained as a result of reproduction of the test data.

Abstract: A DSP of a disc player includes a record signal obtaining portion for obtaining an all sum signal that is a total sum of electric signals corresponding to all reflection light obtained by an optical pickup by projecting a laser beam from an LD for BD to a reproduction data area an optical disc, which stores information to be reproduced, a test signal obtaining portion for obtaining another all sum signal by projecting the laser beam from the LD for BD to a calibration area of the optical disc where a distance from the center position is within the range of 21.3 to 22.0 millimeters, and a discriminating portion for discriminating whether or not the optical disc is a BD based on the all sum signal obtained by the record signal obtaining portion and the another all sum signal obtained by the test signal obtaining portion.

Abstract: Embodiments of the present invention help to reduce the occurrence of read hard errors in a hard disk drive (HDD). According to one embodiment, a HDD rewrites data on all data tracks of a block M when the number of write operations to the block consisting of continuous plural data tracks. The HDD further rewrites data on continuous plural data tracks and adjacent to the block. Since the number of write operations is counted every block, a memory area to register the number of write operations can be reduced.

Abstract: According to one embodiment, an information recording apparatus comprises a recording unit which records information in blocks in a rewritable medium, a buffer which stores recording information of blocks while performing update, and stops the update of information when the write error is detected, an identifying unit configured to play back recording information of the information recording medium corresponding to the blocks when the write error is detected, and to identify a block including a write error occurring position based on whether a playback of the recording information has succeeded or not, and a re-recording unit configured to re-record the block identified by the identifying unit.

Abstract: A tracking control is performed based on a first tracking error signal obtained from a first light beam reflected on an optical recording medium and a second tracking error signal obtained from a second light beam reflected on the optical recording medium. The first tracking error signal is corrected when recording information to or reproducing information from a first information recording layer that includes a first area facing an area on a second information recording layer with no information recorded and a second area facing an area on the second information recording layer with information recorded.

Abstract: Inspection with respect to a defect on a surface of a substrate with an inherent or partial wave-like distortion is performed with high accuracy in consideration with the fluctuation caused by the wave-like distortion detected by the defect in excess of the signal level. The substrate is diagonally illuminated while being rotated and moved toward one axial direction to detect the specular reflected light and the scattered light. Based on the detected signal waveform, the state with respect to the inherent or partial wave-like distortion is determined. When the wave-like distortion exists in the substrate, the waveform is divided, and the threshold value is set for the divided regions. The signal higher than the threshold value will be output or displayed as the defect.

Abstract: In a device for detecting a focus error in controlling a position in an optical axis, a laser beam is split into first and second beam components, and one of the first and second beam components is diverged or converged. Then, the first and second beam components are superposed on each other, providing a single laser beam. The single laser beam is applied to an optical data-recording medium through an objective lens. The first laser beam component is focused on a first focusing point that is set at one side of the pinhole. The second beam component is focused on a second focusing point that is set at the other side of the pinhole.

Abstract: Embodiments of the present invention provide a servo write medium, method and device for writing servo information by self servo write on the servo region formed from a flat section of the discrete track medium. The recording or write device yields the same servo characteristics as magnetic servo writing, is superior to pre-patterned servo, and delivers a greater write storage capacity with an even higher recording density. According to one embodiment, a self servo write method is used to write servo information on a flat section formed on a patterned disk on which discrete tracks are formed. Timing detection patterns (grooves) required for controlling the timing along the periphery during self servo write are formed by pre-patterning on the disk, and RRO error signals used for positioning control along the radius are written in the servo information on a flat section of the disk.

Abstract: A write-once read-many information recording medium is provided, which is capable of easily searching for a latest DDS and a latest defect list. At least one disc management working area is sequentially allocated in a predetermined direction on the write-once read-many information recording medium of the present invention. The latest defect list and the latest DDS are provided in a recorded disc management working area neighboring a border between the recorded disc management working area and an unrecorded disc management working area, where the latest defect list precedes the latest DDS in the predetermined direction.

Abstract: A method of detecting optical disc error information on an optical disc, for applying in an optical disc drive, the method comprising: first, detecting whether the optical disc is blank, if not, perform the following: checking whether a seek error occurred, if yes, recording a seek error mark; while reading a data region, recording data error information, the data error information comprises an error count, and a corresponding data error location; finally, outputting the optical disk error information according to the data error information and the seek error mark.

Abstract: The recorder/reproducer (101), when moving a first content data, writes a second content data, which is obtained by re-coding the first content data recorded in a first recording medium, into a second recording medium instead of the first content data, writes one or more first partial information extracted from the first content data into the second recording medium, and makes the first content data irreproducible, using one or more first invalidated partial information having one-to-one correspondence with the extracted one or more first partial information. When restoring the first content data, it makes the irreproducible first content data reproducible, using the one or more first partial information recorded in the second recording medium.

Abstract: According to the present invention, light is emitted by a light source at different emission intensities, and sensor output values are compared with threshold values at the individual emission intensities, so that the types of recording media having various reflection characteristics can be correctly determined.

Abstract: The invention relates to a method of optimizing an optical drive system 101 capable of recording and/or reproducing data to and from an optical carrier 102, such as the high number of different types present e.g. a CD, DVD-SL, DVD-DL, HD-DVD or BD carrier More specifically, the invention relates to improved radial tracking error signal in the optical drive system and thereby alternatively or additionally also improved carrier recognition in the optical drive system. Disc recognition may be a cumbersome procedure due to influences such as the high number of carrier types present, the tolerances specified for and quality of the carriers, the tolerances within the optical system. E.g.

Abstract: A write-once read-many information recording medium is provided, which is capable of easily searching for a latest DDS and a latest defect list. At least one disc management working area is sequentially allocated in a predetermined direction on the write-once read-many information recording medium of the present invention. The latest defect list and the latest DDS are provided in a recorded disc management working area neighboring a border between the recorded disc management working area and an unrecorded disc management working area, where the latest defect list precedes the latest DDS in the predetermined direction.

Abstract: An adaptive writing method of a high-density optical recording apparatus and a circuit thereof. The circuit includes a discriminator for discriminating a magnitude of a present mark of input NRZI data and magnitudes of leading and/or trailing spaces of the input NRZI data, a generator for controlling the waveform of a write pulse in accordance with the magnitude of the present mark of the input NRZI data and the magnitudes of the leading and/or trailing spaces of the input NRZI data to generate an adaptive write pulse, and a driver for driving a light source by converting the adaptive write pulse into a current signal in accordance with driving power levels for respective channels of the adaptive write pulse. The widths of the first and/or last pulses of the write pulse waveform are varied in accordance with the magnitude of the present mark of input NRZI data and the magnitude of the leading and/or trailing spaces, thereby minimizing jitter to enhance system reliability and performance.

Abstract: A method for to restore quantization data to binary data in a system for recording and/or reproducing the binary data includes selecting a selection region predicted to include an alignment mark from the quantization data, determining a location of the alignment mark within the selection region; and converting the quantization data to the binary data based on a comparison of the determined location of the alignment mark and an original location of the alignment mark.

Abstract: An adaptive writing method of a high-density optical recording apparatus and a circuit thereof. The circuit includes a discriminator for discriminating a magnitude of a present mark of input NRZI data and magnitudes of leading and/or trailing spaces of the input NRZI data, a generator for controlling the waveform of a write pulse in accordance with the magnitude of the present mark of the input NRZI data and the magnitudes of the leading and/or trailing spaces of the input NRZI data to generate an adaptive write pulse, and a driver for driving a light source by converting the adaptive write pulse into a current signal in accordance with driving power levels for respective channels of the adaptive write pulse. The widths of the first and/or last pulses of the write pulse waveform are varied in accordance with the magnitude of the present mark of input NRZI data and the magnitude of the leading and/or trailing spaces, thereby minimizing jitter to enhance system reliability and performance.

Abstract: A data recording method according to the present invention is a method for recording data as edge position information, including marks and spaces of multiple different lengths, on a storage medium by irradiating the storage medium with a pulsed energy beam. The method includes the steps of: (A) generating a write code sequence based on the data to be recorded; (B) determining a write pulse waveform, defining the power modulation of the energy beam, according to the code lengths of respective codes included in the write code sequence; and (C) modulating the power of the energy beam based on the write pulse waveform.

Abstract: According to one embodiment, a preset amount of padding data is added while a block number corresponding to a detecting period of sync information which becomes shorter is used as a packing unit when the detecting period of the sync information becomes shorter than an original period, and a block number corresponding to a detecting period of the sync information which becomes longer is divided while an original number of blocks contained in one packing unit is set as an upper limit and a preset amount of padding data is added with each divided block number used as a packing unit when the detecting period of the sync information becomes longer than the original period.

Abstract: A method and device for recording multiple information volumes on a record carrier, usually called multi-session recording, has a mapping unit (31) for opening a session by recording intro data including a first buffer zone at the beginning of the start zone of the volume, and a session control block (SDCB) in a remaining blank area of the start zone after the buffer zone. The session control block includes volume data indicative of the status and the contents of the session. The session is closed by recording session control data indicating that the information volume is closed in the remaining blank area, and closure data after the last user information recorded in the data zone for constituting the end zone of the volume. Further, the device has a detecting unit (32) for retrieving the session control block from said start zone.

Abstract: A multi-layer disc medium includes two or more reproducing or recording and reproducing layers. One or more layers have a layer information area portion formed by at least a part of a circular path extending circumferentially of the layer. The circular paths have a center coincident with a center axis of rotation of the disc medium and are at substantially identical radial positions from the center axis of rotation of the disc medium. Layer information capable of identifying a layer concerned is disposed on at least the part of the circular path on the layer. By reading the layer information at an inter-layer transference, verification of an accessed layer can be performed simply and quickly, leading to a simple and quick inter-layer transference.

Abstract: An identification input device and a temperature detector that detects body temperature data. The identification input device may be an optical touch pen. The infrared touch pen may be affixed to the temperature detector using a hook and connector or a snap fit connector. In use, the temperature detector computes body temperature data and the identification input device determines an identifier. The identifier is unique to a user. After obtaining the body temperature data and identifier, a transmitter may transmit body temperature data and the identifier over a wireless communications path to a processing unit. By transmitting data over a wireless communications path, an individual's data or a large group of data may be analyzed and viewed via a display unit.

Abstract: An optical information recording medium includes a recording layer in which information can be recorded as a hologram by using a phenomenon of interference between an information light beam and a reference light beam. The recording layer is sandwiched between substrates. A thin film layer that is laminated on the substrate on light output side. Openings are formed in the recording layer and those openings allow passage of the information light beam and the reference light beam.

Abstract: An optical disc apparatus that records recording marks in a plurality of mark layers by irradiating predetermined light onto a disc-like volume type recording medium on the basis of information to be recorded is disclosed. The apparatus includes: a first focus position adjusting means for adjusting the position of a focus on which a first light beam focuses within the volume type recording medium, in the direction of an optical axis of the first light beam; a second focus position adjusting means for adjusting the position of a focus on which a second light beam focuses within the volume type recording medium, in the direction of an optical axis of the second light beam; a focus control means for controlling the first focus position adjusting means and the second focus position adjusting means; and a recording control means for forming the recording marks at the positions of respective focuses.

Abstract: A hologram recorder includes a light source for emitting a laser beam, a polarizing beam splitter for splitting the laser beam into a recording beam and a reference beam in accordance with a state of polarization, and a rotary polarizer located between the light source and the polarizing beam splitter. The rotary polarizer has the function of optical rotation, whereby a polarization component to be the recording beam is increased from the central portion toward the peripheral portion of the laser beam, and a polarization component to be the reference beam is decreased from the central portion toward the peripheral portion of the laser beam.

Abstract: An optical disc apparatus reproducing information on the basis of a standing wave recorded on a disc-like volume type recording medium is disclosed. The apparatus includes: first focus position adjusting means for adjusting the position of a focus on which a first light beam focuses inside a recording layer inside the volume type recording medium in the optical axis direction of the first light beam; second focus position adjusting means for adjusting the position of a focus on which a second light beam focuses inside the recording layer in the optical axis direction of the second light beam; controlling means for controlling the first focus position adjusting means and the second focus position adjusting means; and first and second detecting means for detecting the first and second reproduction light beams.

Abstract: A switchable optical unit, capable of controlling a beam of radiation (b) passing through an optically active portion (8) of the unit, comprises a fluid chamber (10) including an electrically conductive liquid (18), which chamber comprises a pair of first electrodes (20,22) fixed to the chamber inner walls (12,14) at the position of the optically active portion and second electrode means (24) fixed to inner walls of the chamber outside the optically active portion and a third electrode (28) connected to the conductive liquid. By applying a voltage (V) to the first electrodes and the second electrode means, respectively the conductive liquid can be moved in and out the optically active portion so that the unit (1) is switched between a least two discrete states.

Abstract: An optical compensator for use in an optical scanning device for scanning a first optical record carrier (3?) having an information layer (2?) at a first information layer depth d and a second optical record carrier (3?) having an information layer (2?) at a second, different information layer depth d2. The scanning of the first and second optical record carrier is effected using a scanning spot (16) formed on the information layer by a first radiation beam having a first wavelength and a second radiation beam having a second, different wavelength respectively. The optical compensator includes a substantially circular phase structure having an annular zone arranged in the path of the first radiation beam and the second radiation beam.

Abstract: An optical head device may include a polarization conversion element disposed on a common optical path for guiding a first and a second laser beams to a common objective lens for converting the first and the second laser beams to a circularly polarized light from a linearly polarized light, and a ½-wavelength plate disposed on an optical path of the first laser beam from a first laser light source to the common optical path for adjusting a polarization plane direction of the first laser beam. A polarization plane direction of the first laser beam incident on the polarization conversion element from the first laser light source is adjusted by the ½-wavelength plate in a direction so that the linearly polarized light is converted into the circularly polarized light.

Abstract: An objective lens corresponding to a BD beam light, and an objective lens corresponding to a DVD/CD beam light are arranged parallel to an optical disc. One rising mirror is arranged in a tilted manner on a side opposite to the optical disc of the objective lenses. A first film for reflecting the BD beam light emitted from a laser diode and making the beam light enter the objective lens and transmitting the DVD/CD beam light emitted from a laser diode is arranged on one of the parallel surfaces of a transparent substrate of the rising mirror. A second film for reflecting the DVD/CD beam light transmitted through the first film and the transparent substrate and making the beam light enter the objective lens is arranged on the other surface. An incident optical axis to each objective lens of the BD beam light and the DVD/CD beam light is branched with the rising mirror.

Abstract: An optical head device may include a first laser light source, a second laser light source, a first parallel-plate type beam splitter for guiding a first and a second laser beams to a common objective lens, a second parallel-plate type beam splitter for guiding the second laser beam to the common objective lens, an aberration correction lens disposed between the first laser light source and the first beam splitter for correcting an aberration generated when the first laser beam transmits through the first beam splitter; and a light source unit which is structured by fixing the first laser light source and the aberration correction lens to a common holder in a state that a relative position between the first laser light source and the aberration correction lens is previously set.

Abstract: A spin FET includes a first ferromagnetic film disposed on a first source/drain area, a direction of magnetization thereof being fixed in an upward direction or a downward direction perpendicular to a film surface, a second ferromagnetic film disposed on a second source/drain area, a direction of magnetization thereof being changed in the upward direction or the downward direction, an anti-ferromagnetic ferroelectric film disposed on the second ferromagnetic film, and a tunnel barrier film disposed at least between the first source/drain area and the first ferromagnetic film or between the second source/drain and the second ferromagnetic film. Resistance of the anti-ferromagnetic ferroelectric film is larger than ON resistance when the first and second source/drain areas conduct electricity through the channel area.

Abstract: A recording and reproducing apparatus supports a recording medium swingably in at least two axis directions by a support section formed in a shape having elasticity. When an access can be made to a memory, the recording medium is constantly and reciprocatingly moved in a direction along data row. Thus, a positional relationship with a probe head is always grasped. When an access is made, a moving time associated with position identification is reduced, and precise and fast movement is achieved.

Abstract: A nonvolatile information recording and reproducing device exhibits low power consumption and high thermal stability. The information recording and reproducing apparatus according to an aspect of the present invention includes a recording layer and a unit for recording information by applying a voltage to the recording layer to generate a resistance change to be caused due to a phase change in the recording layer. The recording layer includes a material having a ramsdelite structure.

Abstract: A writable optical information recording medium, an apparatus for reproducing the same, and a method of determining the same are provided. The amplitude of a push-pull signal (PPS) of the writable optical information recording medium is determined to be within an amplitude range of a PPS of a reproduction-only optical information recording medium. Accordingly, it is possible to stably reproduce copy protected content by recognizing a loaded writable optical information recording medium as a medium of a reproduction-only type.

Abstract: An optical recording medium is provided which includes two or more information layers in which an Sb-based eutectic material is used as the material for a recording film of a translucent information layer. There is also provided a recording film material for the optical recording medium. The translucent information layer is configured to include a recording film formed of a phase change material SbxGeyInz containing Sb, Ge, and In in an atomic ratio of x:y:z, where 5?y?15 and 4?z?15 are satisfied. The recording film further includes Te in an atomic ratio of a, provided that x+y+z+a=100 and 4?a?15 are satisfied. An interface layer formed of a ZrO2—Cr2O3 film having a thickness of 2 nm or more and 10 nm or less is provided on the laser beam incident side of the recording film. When the compositional ratio of the ZrO2—Cr2O3 film is given by ZrO2:Cr2O3=B:C (mol %), 20?B?90, 10?C?80, and B+C=100 are satisfied.

Abstract: According to an embodiment, the invention is directed to an optical disc having signal tracks including a groove track, in which wobble signals are recorded on at least the groove track. Wobble units of wobble signals are modulated on the groove track, while at least 4 wobble units are used to represent a data bit of “0” or “1” in address information. Data bit of “0” or “1” in address information has a same phase and different phase with regard to alternate data bit at least to distinguish from each other.

Abstract: A method and apparatus for mitigating the effect of adjacent channel interference in a multicarrier modulation system is provided. The method includes receiving an encoded signal over multiple subcarriers at different frequencies. The signal includes a plurality of pilot symbols and data symbols modulated onto the subcarriers using a modulation technique. Further, the method includes: grouping the subcarriers into multiple sets of subcarriers based on their frequencies, wherein each set includes one or more subcarriers; estimating, for each set of subcarriers, a noise value associated with at least a portion of the pilot symbols received over subcarriers included in the set; and generating a decoded signal comprising a plurality of decoded data bits, using the estimated noise values.

Abstract: Signals in a multi-channel, impaired communication system are post-processed at the receiver. A triangular matrix Decision Feedback Demodulator (DFD) at the receiver extracts channels without requiring delivery of receiver parameters to the transmitter. Multi-Input Multi-Output (MIMO) processing matrices and DFD parameters are computed by first applying matrix transformations to diagonalize the noise covariance matrix of the multiple channels received at the receiver. QR decompositions (i.e., decompositions into orthogonal and triangular matrices) are then applied to the main channels to obtain triangular channel matrices. The noise-diagonalizing transformations and QR decompositions are then combined to form the MIMO postprocessing matrices and DFD parameters. MIMO postprocessing matrices and DFD parameters are computed from training data and then adapted during live data transmission.

Abstract: Embodiments disclose a method of coordinating reception of uplink transmissions in order to reduce interference among transceivers in an OFDM wireless transmission system, or similar communication system, including a number of receivers communicating with one or more basestations in cell or sector arrangements. A basestation within each sector includes an uplink coordinated reception process that imposes coordinated reception techniques across sector or cell boundaries in order to improve uplink transmission quality between target terminals and basestations within each sector.

Abstract: A cancellation system is disclosed for processing incoming and outgoing signals in a transform domain to create a cancellation signal for reducing or removing unwanted interference. Data is ordered based on Good-Thomas indexing into a two dimensional array in a buffer. The two dimensional array may have lr rows and lw columns. From the buffer, the columns of data undergo a Winograd small transform. The rows of data undergo a Cooley-Tukey operation to complete the transform operation into the frequency domain. Multipliers scale the transformed data to generate a cancellation signal in the frequency domain. Inverse (Cooley-Tukey) and Winograd transforms perform inverse processing on the cancellation signal to return the cancellation signal or data to the time domain. Re-ordering the data and combination of the cancellation signal or data with incoming or outgoing signals achieve interference cancellation.

Abstract: A method of demapping in a receiver including deriving M intermediate soft bit values yj for each of the I and Q data of the input signal as a function of the spacing in the constellation; and limiting the range of the M values yj. A look-up table index is derived for each of the limited M values yj. A look-up table, having 2N+1 entries for supporting up to N soft bit outputs, is indexed using the derived indices; and K soft bits for each of the M values yj of the I and Q data are outputted.

Abstract: A system and method for determining an FFT window location for reception of an OFDM signal received over a transmission channel. The OFDM signal includes a plurality of symbols each having a guard interval. The system includes a correlation module that determines a location of maximum correlation in a first symbol, an FFT module to perform an FFT on the OFDM signal based upon an initial FFT window location, and an adjustment module. The adjustment module determines a plurality of permissible echo location options based upon the initial FFT window location, selects a permissible echo location option that corresponds most closely to the location of maximum correlation, and adjusts the initial FFT window location based upon the selected permissible echo location option so that the adjusted FFT window location includes substantially all of a useful symbol length of the first symbol while a maximum number of echoes are included within the guard interval of the first symbol.