Patents by Inventor Pi-Hai Liu

Pi-Hai Liu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20070086315
    Abstract: Optical disc apparatuses. The apparatus comprises an optical pickup and a data recovery unit. The optical pickup irradiates laser light onto a disc, receives light reflected from the disc, and generates an RF signal in response to the received light. The data recovery unit comprises a first configuration and a second configuration. The data recovery unit receives the RF signal from the optical pickup, reproduces data according to the RF signal in the first configuration, and performs a signal quality index measurement of the RF signal in the second configuration.
    Type: Application
    Filed: October 19, 2005
    Publication date: April 19, 2007
    Inventors: Chao-Ming Huang, Yuh Cheng, Gwo-Huei Wu, Pi-hai Liu, Chih-Yuan Chen
  • Publication number: 20070080836
    Abstract: A modulation system includes an encoder for transferring data words to tentative code words. A DSV control bit generator determines the value of a DSV control bit according to the data words or the tentative code words to optimize the cumulative DSVs corresponding tentative code words, wherein the DSV control bit generator determines the value of a current DSV control bit when at least a subsequent DSV control bit is detected. A final code word generator generates final code words according to the determined DSV control bit and the tentative code words.
    Type: Application
    Filed: October 18, 2006
    Publication date: April 12, 2007
    Inventors: Hsin-Cheng Chen, Pi-Hai Liu, Ming-Yang Chao
  • Publication number: 20070058764
    Abstract: A phase detection device comprising an analog-digital converter, an interpolator, and a determining unit. The analog-digital converter receives an analog signal and converts the analog signal to a digital signal according to a plurality of digital sampling points. The interpolator generates a plurality of interpolation points according to a predetermined amount of digital sampling points. The determining unit obtains a phase of the ZC point according to the interpolation points or the digital sampling points.
    Type: Application
    Filed: September 9, 2005
    Publication date: March 15, 2007
    Inventors: Yuh Cheng, Pi-Hai Liu, Meng-Ta Yang
  • Publication number: 20070011591
    Abstract: The present invention discloses a method for generating a syndrome value of an error correction codeword (ECC), and a related apparatus. The ECC includes a fixed section, an information section, and a parity section. The fixed section includes not only byte “00”. The method provides a fixed syndrome value according to characteristics of the ECC. The syndrome value corresponding to the ECC is generated according to the fixed syndrome value, the information section, and the parity section.
    Type: Application
    Filed: June 1, 2006
    Publication date: January 11, 2007
    Inventors: Li-Lien Lin, Pi-Hai Liu
  • Publication number: 20070008194
    Abstract: Disclosed is a method for converting an input code into an output code. The method includes: determining a plurality of input code subsets of the input code; converting the input code subsets into a plurality of output code subsets, respectively; and merging the output code subsets to generate the output code.
    Type: Application
    Filed: March 23, 2006
    Publication date: January 11, 2007
    Inventors: Jia-Horng Shieh, Pi-Hai Liu
  • Patent number: 7142135
    Abstract: In a high-density optical storage system, data words are modulated into code words in a manner of minimizing the fluctuation of the digital sum value (DSV). A cumulative DSV is calculated for each possible value of a DSV control bit. The DSV control bit is determined to minimize the absolute cumulative DSV when detecting at least one subsequent DSV control bit or after a predetermined delay. A corresponding code word is generated according to the determined current DSV control bit.
    Type: Grant
    Filed: September 6, 2005
    Date of Patent: November 28, 2006
    Assignee: Media Tek Inc.
    Inventors: Hsin-Cheng Chen, Pi-Hai Liu, Ming-Yang Chao
  • Publication number: 20060215524
    Abstract: A system, for tuning a plurality of write strategy parameters of an optical storage device, includes: a run-length limited (RLL) meter for detecting a plurality of lengths, each length corresponding to a pit or a land on an optical storage medium accessed by the optical storage device; and a calculation module coupled to the RLL meter for performing calculations according to the lengths to generate a plurality of calculation results; wherein the write strategy parameters are tuned according to the calculation results.
    Type: Application
    Filed: December 16, 2005
    Publication date: September 28, 2006
    Inventors: Pi-Hai Liu, Yuh Cheng, Chih-Ching Yu, Chih-Hsiung Chu
  • Patent number: 7106226
    Abstract: A key bit position of a first Gray code is determined based on the bit values of the first Gray code. The first Gray code and a second Gray code that differs from the first Gray code only in the key bit position correspond to two associated numbers that differ by one.
    Type: Grant
    Filed: September 28, 2004
    Date of Patent: September 12, 2006
    Assignee: MediaTek, Inc.
    Inventors: Pi-Hai Liu, Jia-Horng Shieh
  • Patent number: 7071847
    Abstract: An encoding method of recording media is used to speed up the encoding procedure in a recording media. Different conditions of states and paths set in advance during the encoding procedure to simply the actual operation loading for possible paths in the look-ahead calculation, thereby achieving fast encoding. Using the method, the operation of the look-ahead calculation of an exponential growth is greatly reduced to a linear growth.
    Type: Grant
    Filed: September 3, 2004
    Date of Patent: July 4, 2006
    Assignee: Industrial Technology Research Institute
    Inventors: Yung-Chi Yang, Pi-Hai Liu
  • Publication number: 20060133224
    Abstract: An address-accessing device includes first and second information generators for producing first and second information according to the received address signals; a phase offset detector for producing a phase offset according to the first and second information; a reference signal generator for producing a reference signal according to the phase offset, the first information and the second information; and a decoder used to determine the structure type of an address-in-pregroove unit (ADIP) according to the reference value. This address-accessing device is capable of adjusting the decision level and the phase offset automatically to lower the error rate occurring in the address access procedure.
    Type: Application
    Filed: April 15, 2005
    Publication date: June 22, 2006
    Inventors: Pi-Hai Liu, Chun-Nan Chen
  • Publication number: 20060133255
    Abstract: A read channel apparatus is disclosed for reading data recorded on an optical storage system. An exemplary sampling device samples an analog read signal generating from the optical storage system to generate a sequence of sample values. A subtractor subtracts an estimated DC offset from the sample values to generate a sequence of DC-removed sample values. An equalizer equalizes DC-removed sample values in accordance with a target spectrum to generate a sequence of equalized sample values. First and second interpolators interpolate the equalized sample values to respectively generate sequences of even-time sample values and odd-time sample values. A data sequence composed of the even-time and the odd-time sample values is substantially synchronized to the baud rate. A timing recovery controller controls the interpolators to synchronize the even-time and odd-time sample values to the baud rate.
    Type: Application
    Filed: February 13, 2006
    Publication date: June 22, 2006
    Inventors: Tzu-Pai Wang, Meng-Ta Yang, Pi-Hai Liu
  • Publication number: 20060114982
    Abstract: An adaptive equalizer and the related method are disclosed. The adaptive equalizer is capable of adjusting its own equalization coefficients, and includes a reference signal generator for generating a reference signal according to a first reference source, an equalization unit for generating an equalized signal by processing a received signal through a plurality of equalization coefficients, a weighted signal generator for generating a weighted signal according to a second reference source, and a coefficient adapting circuit for adjusting the equalization coefficients according to the reference signal, the equalized signal, the weighted signal, and the received signal.
    Type: Application
    Filed: August 8, 2005
    Publication date: June 1, 2006
    Inventors: Pi-Hai Liu, Meng-Ta Yang
  • Publication number: 20060088118
    Abstract: A path metric computing method applied in a high-speed Viterbi detector and related apparatus thereof are disclosed. The path metric computing apparatus includes a comparator for generating a control signal according a plurality of previous path metrics, a combining circuit for generating a plurality of first output values according to the previous path metrics and branch costs of a plurality of branches of a current state, and a multiplexer, electrically connected to the comparator and the combining circuit, for determining a first path metric of the current state according to the control signal and the output values.
    Type: Application
    Filed: July 26, 2005
    Publication date: April 27, 2006
    Inventors: Wen-Yi Wu, Meng-Ta Yang, Pi-Hai Liu
  • Publication number: 20060077849
    Abstract: A method utilized for detecting a physical mark in a signal read from an optical disc, including: generating a matching signal capable of being utilized to identify the physical mark according to a reference clock and a wobble clock; generating a comparison signal by comparing the matching signal and a wobble data signal; determining whether a period of which the level of the comparison signal surpass a predetermined level within a predetermined period is greater than a threshold or not; and if the period greater than the threshold, generating an indication signal corresponding to the location of the physical mark. Wherein the wobble data signal and the wobble clock is generated according to the read back signal.
    Type: Application
    Filed: June 17, 2005
    Publication date: April 13, 2006
    Inventors: Chun-Nan Chen, Wen-Yi Wu, Pi-Hai Liu
  • Publication number: 20060066461
    Abstract: A key bit position of a first Gray code is determined based on the bit values of the first Gray code. The first Gray code and a second Gray code that differs from the first Gray code only in the key bit position correspond to two associated numbers that differ by one.
    Type: Application
    Filed: September 28, 2004
    Publication date: March 30, 2006
    Inventors: Pi-Hai Liu, Jia-Horng Shieh
  • Publication number: 20060044960
    Abstract: An apparatus for detecting physical marks from a wobble signal includes a matching value operation unit, a threshold value generator and a physical mark indicator. A wobble signal is converted into a matched signal by the matching value operation unit according to the waveform difference between a normal clock signal or a specific matching reference signal and itself, wherein the matching reference signal needs to highlight the existed physical mark. The physical mark indicator designates a threshold value that depends on the status of the wobble signal, and compares the matched signal with the threshold value to output a physical mark indication signal. The threshold value is selected from at least two different default values. Furthermore, a decoder is employed to convert the physical mark indication signal into wobble data with physical address information.
    Type: Application
    Filed: October 11, 2004
    Publication date: March 2, 2006
    Applicant: Mediatek Inc.
    Inventors: Pi-Hai Liu, Chun-Nan Chen
  • Publication number: 20060044959
    Abstract: An apparatus for detecting physical marks from a wobble signal includes a matching value operation unit, a threshold value generator and a physical mark indicator. A wobble signal is converted into a matched signal by the matching value operation unit according to the waveform difference between a normal clock signal or a specific matching reference signal and itself, wherein the matching reference signal needs to highlight the existed physical mark. The physical mark indicator designates a threshold value that depends on the status of the wobble signal, and compares the matched signal with the threshold value to output a physical mark indication signal. The threshold value is selected from at least two different default values. Furthermore, a decoder is employed to convert the physical mark indication signal into wobble data with physical address information.
    Type: Application
    Filed: August 13, 2004
    Publication date: March 2, 2006
    Applicant: MEDIATEK INC.
    Inventors: Pi-Hai Liu, Chun-nan Chen
  • Patent number: 7006020
    Abstract: An encoding and decoding method of record medium having the concept of type and set is disclosed. The disclosed not only satisfy the DK-Constraint, the coding rate and DC-free control are better through the auxiliary conditions of type dependency and digital sum value. The available storage space of the record medium consequently increases. In the decoding procedures, the accuracy and efficiency are better through the auxiliary conditions of type dependency and forbidden type set. Thus, the decoding error consequently decreases.
    Type: Grant
    Filed: July 7, 2003
    Date of Patent: February 28, 2006
    Assignee: Industrial Technology Research Institute
    Inventors: Pi-Hai Liu, Yung-Chi Yang
  • Publication number: 20050232104
    Abstract: An apparatus for identifying the address in pregroove (ADIP) of a Blu-ray disc is described. The apparatus uses a statistical scheme or distance-finding scheme to find the position of a predetermined minimum shift keying (MSK) mark or the first MSK mark, i.e. a bit sync unit, from an ADIP unit to identify data of the ADIP unit. The present invention doesn't have the error propagation effect occurring in the prior art so that the error rate for ADIP identification can be greatly reduced.
    Type: Application
    Filed: January 26, 2005
    Publication date: October 20, 2005
    Inventors: Chun-Nan Chen, Wen-Yi Wu, Pi-Hai Liu
  • Publication number: 20050140526
    Abstract: An encoding method of recording media is disclosed to speed up the encoding procedure in a recording media. Different conditions of states and paths set in advance during the encoding procedure to simply the actual operation loading for possible paths in the look-ahead calculation, thereby achieving fast encoding. Using the disclosed method, the operation of the look-ahead calculation of an exponential growth is greatly reduced to a linear growth.
    Type: Application
    Filed: September 3, 2004
    Publication date: June 30, 2005
    Applicant: Industrial Technology Research Institute
    Inventors: Yung-Chi Yang, Pi-Hai Liu