Patents by Inventor Jong-Keung Cheng

Jong-Keung Cheng 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).

  • Patent number: 9843218
    Abstract: A wireless charging system, a wireless power transmitter, and a wireless transmitting method are provided. The method includes generating a pulse width modulation signal having an operating frequency according to a parameter, transmitting a power signal according to the pulse width modulation signal, generating a sampling frequency according to the operating frequency, obtaining power adjusting information from a transmission coil according to the sampling frequency, and adjusting the parameter according to the power adjusting information. The sampling frequency is the product of the operating frequency and a multiple, and the multiple is the summation of an offset and a positive integer. The offset is in the range of 0.25 to 0.75.
    Type: Grant
    Filed: February 2, 2016
    Date of Patent: December 12, 2017
    Assignee: NEWEDGE TECHNOLOGIES, INC.
    Inventors: Chen Liu, Tim Hui-Hung Lu, Jong-keung Cheng
  • Publication number: 20170047763
    Abstract: A wireless charging system, a wireless power transmitter, and a wireless transmitting method are provided. The method includes generating a pulse width modulation signal having an operating frequency according to a parameter, transmitting a power signal according to the pulse width modulation signal, generating a sampling frequency according to the operating frequency, obtaining power adjusting information from a transmission coil according to the sampling frequency, and adjusting the parameter according to the power adjusting information. The sampling frequency is the product of the operating frequency and a multiple, and the multiple is the summation of an offset and a positive integer. The offset is in the range of 0.25 to 0.75.
    Type: Application
    Filed: February 2, 2016
    Publication date: February 16, 2017
    Inventors: Chen Liu, Tim Hui-Hung Lu, Jong-keung Cheng
  • Patent number: 5689816
    Abstract: In accordance with IS-136 standard, an analog wireless signal and a digitally encoded wireless signal can be received by a remote telecommunicating device. The remote device can differentiate between the analog wireless signal and the digitally encoded wireless signal by measuring the average energy of the signal in the portion of the baseband signal that is expected to contain the Supervisory Audio Tone signal, and the portion of the baseband signal that is expected to be outside of the audio band for an analog signal. The average energy of the portion outside of the audio band is subtracted from the average energy of the SAT signal. The difference is compared to a threshold, and based upon the comparison, the characteristic of the received wireless signal, i.e. analog or digital, is determined.
    Type: Grant
    Filed: November 2, 1995
    Date of Patent: November 18, 1997
    Assignee: Atmel Corporation
    Inventors: Tony Siuman Lee, Jong-keung Cheng
  • Patent number: 5491726
    Abstract: A digital wireless communication system operates between a first unit and a second unit. The received digitally encoded signal is sampled to produce a first sampled digital signal. A first bank of match filters with each match filter having a different frequency range is used to pass the first sampled digital signal therethrough. The output of the first bank of match filters having the largest amplitude is selected along with the match filter which produced the largest amplitude output. The digitally encoded signal having this "coarse" frequency range is then passed through a second bank of match filters. Each of the match filters has a fine frequency different from one another. The output of the second bank of match filters is produced and the output having the largest amplitude is selected. In addition, the filter producing the largest amplitude from the second bank of match filters is also selected.
    Type: Grant
    Filed: August 17, 1993
    Date of Patent: February 13, 1996
    Assignees: TCSI Corp., Sharp Corporation
    Inventors: Jong-Keung Cheng, Nan-Sheng Lin, Mihran H. Touriguian
  • Patent number: 5438595
    Abstract: In a digital wireless communication system communicating between a mobile unit and a stationary unit, a received digitally encoded signal is sampled to produce a first sampled digital signal having a plurality of symbols. The short term energy over a plurality of a contiguous symbols is measured. The short term energy symbol over a first plurality of a contiguous short term energy points is measured. The short term energy average over a second plurality of contiguous short term energy points is measured. The second plurality of contiguous short term energy points is spaced apart from the first plurality of contiguous short term energy points. The difference between the first short term energy average and the second short term energy average is calculated to derive an estimate of the speed of the mobile unit relative to the base unit.
    Type: Grant
    Filed: August 17, 1993
    Date of Patent: August 1, 1995
    Assignee: Teknekron Communication Systems, Inc.
    Inventors: Jong-Keung Cheng, Ravi Subramanian
  • Patent number: 5436942
    Abstract: An equalization method for digitally encoded signals transmitted in a plurality of non-contiguous time slots has a digitally encoded synchronization signal commencing in each time slot followed by a digitally encoded data signal having a digitally encoded marker signal at a predetermined time period. The synchronization signal of the assigned time slot ("first synchronization signal") and the digitally encoded data signal of the assigned time slot including the marker signal, and the digitally encoded synchronization signal of the immediately succeeding non-assigned time slot ("second synchronization signal") are all stored. The location of the minimum energy point of the stored digitally encoded signals is determined. Equalization is performed starting from the first synchronization signal to the minimum energy point. Then, the equalization commences from the second synchronization signal backwards until the minimum energy point is reached.
    Type: Grant
    Filed: August 17, 1993
    Date of Patent: July 25, 1995
    Assignees: Teknekron Communications Systems, Inc., Sharp Corporation
    Inventors: Jong-Keung Cheng, Nan-Sheng Lin, Biswa Ghosh, Robert Kavaler, Amine Haoui
  • Patent number: 5400368
    Abstract: In a digital wireless communication system, a first unit transmits a digitally encoded signal to a second unit in a plurality of non-contiguous time slots. Within each time slot, the digitally encoded signal has a synchronization signal portion followed by a data signal portion. The second unit has an antenna to receive the synchronization signal portion of the digitally encoded signal. The second unit also has a clock to generate a clock signal at a first rate having a sampling phase. An analog to digital converter receives the clock signal and the synchronization signal and samples the synchronization signal at the first rate to generate a first plurality of symbols. An interpolator receives the first plurality of symbols and interpolates the first plurality of symbols to generate a second plurality of symbols at a second rate. The second rate is a multiple of the first rate.
    Type: Grant
    Filed: August 17, 1993
    Date of Patent: March 21, 1995
    Assignee: Teknekron Communications Systems, Inc.
    Inventors: Jong-Keung Cheng, Nan-Sheng Lin, Mihran Touriguian, Kenkichi Suzuki
  • Patent number: 5200962
    Abstract: A combined data compression/error correction system suitable for use in synchronous communication utilizes a data compressor to produce variable rate compressed data from synchronous data. The variable rate compressed data is applied to a FIFO memory which is monitored to determine when the amount of data in the FIFO drops below a predetermined threshold. When it drops below this threshold, an error correction code generator generates a separator character and an error correction code which is appended to the compressed data in the FIFO. Thus, the additional bandwidth created by data compression is used to provide enhancement to the data integrity by providing a variable level of error correction varying in accordance with the free bandwidth generated by the data compressor.
    Type: Grant
    Filed: November 3, 1988
    Date of Patent: April 6, 1993
    Assignee: Racal-Datacom, Inc.
    Inventors: Ming-Luh Kao, Jong-Keung Cheng
  • Patent number: 4720812
    Abstract: A microprocessor-based system is provided with a non-volatile store (such as a PROM) which stores a bootstrap program, a non-volatile store (such as an EPROM) which stores one or more program overlays, and a programmable volatile store (such as a RAM) which can be written into and read from. When the system is powered up, the microprocessor executes the bootstrap program out of the PROM. The bootstrap program includes instructions which copy the program instructions stored in the EPROM into the RAM. The microprocessor then executes the program instructions out of the RAM. Program instructions may be stored in the EPROM in a plurality of overlays, and individual overlays selected by either the bootstrap program or instructions contained in another overlay may be selectively loaded into the RAM for execution. The EPROM is addressed by a programmable counter which appears to the microprocessor as an input/output device to be written into.
    Type: Grant
    Filed: May 30, 1984
    Date of Patent: January 19, 1988
    Assignee: Racal-Milgo, Inc.
    Inventors: Ming-Luh Kao, Jong-Keung Cheng