Patents by Inventor Jin-Der Wang
Jin-Der Wang 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).
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Patent number: 9638783Abstract: Methods, systems, and devices are described for peer-to-peer or device-to-device location services. Mobile devices with a known location (referred to as landmarks) may broadcast their location information and/or a reference signal for other mobile devices (referred to as targets). Landmarks may determine their location through GPS or other location determining means. Targets may have limited or no connection to location determining services, and they may use broadcast information from landmarks, without a request, to determine the targets' location. The targets may determine absolute and/or relative locations. Once a target device determines its location it may assume a role of a landmark to provide broadcast location information to other devices.Type: GrantFiled: December 12, 2013Date of Patent: May 2, 2017Assignee: QUALCOMM IncorporatedInventors: Georg Karl Hampel, Vincent D. Park, Jin-Der Wang, Junyi Li
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Publication number: 20150168532Abstract: Methods, systems, and devices are described for peer-to-peer or device-to-device location services. Mobile devices with a known location (referred to as landmarks) may broadcast their location information and/or a reference signal for other mobile devices (referred to as targets). Landmarks may determine their location through GPS or other location determining means. Targets may have limited or no connection to location determining services, and they may use broadcast information from landmarks, without a request, to determine the targets' location. The targets may determine absolute and/or relative locations. Once a target device determines its location it may assume a role of a landmark to provide broadcast location information to other devices.Type: ApplicationFiled: December 12, 2013Publication date: June 18, 2015Applicant: QUALCOMM IncorporatedInventors: Georg Karl Hampel, Vincent D. Park, Jin-Der Wang, Junyi Li
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Patent number: 9019895Abstract: Power efficient methods and apparatus for detecting wireless terminals in a relatively small geographic area are described. Wireless terminals transmit discovery signals and/or other signals which may be detected by an access point. Various described methods and apparatus are well suited for embodiments where multiple access points, which obtain power from a common power source and/or via a common power bus, with limited power delivery capability. To address power constraints, access points are controlled by a gateway device coupled to the access points so that one or more access points perform monitoring at different times with one or more access points having their receivers powered off while another access point monitors for wireless terminal signals. Power consumption from the common power source is managed by controlling power consumption associated with monitoring operations performed by one or more access points coupled to a common power source.Type: GrantFiled: January 9, 2013Date of Patent: April 28, 2015Assignee: QUALCOMM IncorporatedInventors: Junyi Li, Vincent D. Park, Jin-Der Wang
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Publication number: 20140192712Abstract: Power efficient methods and apparatus for detecting wireless terminals in a relatively small geographic area are described. Wireless terminals transmit discovery signals and/or other signals which may be detected by an access point. Various described methods and apparatus are well suited for embodiments where multiple access points, which obtain power from a common power source and/or via a common power bus, with limited power delivery capability. To address power constraints, access points are controlled by a gateway device coupled to the access points so that one or more access points perform monitoring at different times with one or more access points having their receivers powered off while another access point monitors for wireless terminal signals. Power consumption from the common power source is managed by controlling power consumption associated with monitoring operations performed by one or more access points coupled to a common power source.Type: ApplicationFiled: January 9, 2013Publication date: July 10, 2014Applicant: QUALCOMM IncorporatedInventors: Junyi Li, Vincent D. Park, Jin-Der Wang
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Patent number: 7123651Abstract: A method of operating a modem generally comprising the steps of (A) transmitting an invalid signal from the modem at each of a plurality of settings for an echo cancelling hybrid of the modem, (B) calculating a plurality of merit values each in response to an echo signal received by the modem in response to the invalid signal, and (C) adjusting the echo cancelling hybrid to a particular setting of the settings determined from the merit values.Type: GrantFiled: July 31, 2002Date of Patent: October 17, 2006Assignee: LSI Logic CorporationInventors: Shirish A. Altekar, Jin-Der Wang, Louis Joseph Serrano
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Publication number: 20040022308Abstract: A method of operating a modem generally comprising the steps of (A) transmitting an invalid signal from the modem at each of a plurality of settings for an echo cancelling hybrid of the modem, (B) calculating a plurality of merit values each in response to an echo signal received by the modem in response to the invalid signal, and (C) adjusting the echo cancelling hybrid to a particular setting of the settings determined from the merit values.Type: ApplicationFiled: July 31, 2002Publication date: February 5, 2004Applicant: LSI LOGIC CORPORATIONInventors: Shirish A. Altekar, Jin-Der Wang, Louis Joseph Serrano
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Patent number: 6628722Abstract: In an Asymmetric Digital Subscriber Loop (ADSL) Discrete Multi-Tone (DMT) system, ADSL DMT equipment includes a decoder that operates on a received DMT signal representing Nf symbols/second, where N>1, to recover f symbols per second. In particular, the decoder decides each symbol value of the recovered signal as a function of values of a respective 2N symbol values from the received DMT signal.Type: GrantFiled: June 19, 1998Date of Patent: September 30, 2003Assignee: Lucent Technologies Inc.Inventors: Rajiv Laroia, Jin-Der Wang
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Publication number: 20030169875Abstract: A modem generally comprising an analog front end circuit, a hybrid circuit, and a variable impedance element. The hybrid circuit may be configured to couple the analog front end circuit to a transmission line. The variable impedance may be disposed within the analog front end circuit and connected to the hybrid circuit to trim an echo cancelling function of the hybrid circuit.Type: ApplicationFiled: July 17, 2002Publication date: September 11, 2003Applicant: LSI LOGIC CORPORATIONInventors: Sang-Soo Lee, Hiroshi Kimura, Ju Hi John Hong, Jin-Der Wang, John P. DeCelles,, Bryan S. Rowan
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Patent number: 6580761Abstract: In an Asymmetric Digital Subscriber Loop (ADSL) Discrete Multi-Tone (DMT) system, ADSL DMT equipment includes an encoder that operates on a DMT input signal representing ƒ symbols/sec. to generate, for transmission, a DMT output signal representing Nƒ symbols/sec., where N>1, and where each symbol from the DMT input signal is generated in a redundant form in the DMT output signal. In one example of a redundant form, each symbol from the DMT input signal is repeated in N consecutive symbol intervals in the DMT output signal. In another example of a redundant form, every N DMT input symbol values are transmitted in 2N consecutive symbol intervals in the DMT output signal. These 2N consecutive symbols in the DMT output signal include 1) N symbols whose values equal the respective N DMT input symbol values and 2) N symbols whose values are a function of the respective N DMT input symbol values.Type: GrantFiled: April 26, 2001Date of Patent: June 17, 2003Inventors: Rajiv Laroia, Jin-Der Wang
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Patent number: 6519291Abstract: An Asymmetric Digital Subscriber Loop (ADSL) Discrete Multi-Tone system has disjoint and adjacent upstream and downstream channels. During the training phase of an ADSL connection, an ADSL DMT transmitter first determines a round trip propagation delay by transmitting a ranging signal to a far-end ADSL endpoint. During the subsequent communications phase, the ADSL transmitter synchronizes transmission of DMT symbols to a reference clock. In addition, the cyclic extensions of each DMT symbol are increased as a function of the propagation delay.Type: GrantFiled: February 3, 1998Date of Patent: February 11, 2003Assignee: Lucent Technologies Inc.Inventors: Nuri Ruhi Dagdeviren, George John Kustka, Rajiv Laroia, Jin-Der Wang
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Patent number: 6331996Abstract: A known training sequence of binary, pseudo random signals, PN, is received over the channel and correlated with a modified pseudo random sequence PN−1 in which the zeros of the known sequence PN have been mapped to −1. A transform of the correlator output will be observed to contain strong tones that indicate the degree of frequency offset. To facilitate synchronization in the presence of an unknown amount of frequency offset, the received signals may be rectified and the correlation step performed with the absolute value of the incoming signal to obtain new output samples. When the frequency offset is small its measurement is facilitated by modulating the incoming signals with a known, comparatively large frequency offset, before the correlation step to make sure that the overall frequency offset occurs around a frequency that is an integral multiple of the symbol rate divided by the number of symbols in the pseudo random sequence.Type: GrantFiled: May 28, 1998Date of Patent: December 18, 2001Assignee: Lucent Technologies Inc.Inventors: Jenn-Shing Lin, Richard Rogoszewicz, Jin-Der Wang
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Publication number: 20010036233Abstract: an Asymmetric Digital Subscriber Loop (ADSL) Discrete Multi-Tone (DMT) system, ADSL DMT equipment includes an encoder that operates on a DMT input signal representing f symbols/sec. to generate, for transmission, a DMT output signal representing Nf symbols/sec., where N>1, and where each symbol from the DMT input signal is generated in a redundant form in the DMT output signal. In one example of a redundant form, each symbol from the DMT input signal is repeated in N consecutive symbol intervals in the DMT output signal. In another example of a redundant form, every N DMT input symbol values are transmitted in 2N consecutive symbol intervals in the DMT output signal. These 2N consecutive symbols in the DMT output signal include 1) N symbols whose values equal the respective N DMT input symbol values and 2) N symbols whose values are a function of the respective N DMT input symbol values.Type: ApplicationFiled: April 26, 2001Publication date: November 1, 2001Inventors: Rajiv Laroia, Jin-Der Wang
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Patent number: 5881108Abstract: The problem of error propagation is resolved by using the communications channel to adapt a pre-equalizer of a transmitter, in response to changes in the communications channel. In particular, the pre-equalizer adapts to changes in the communications channel by processing an error signal that is communicated over a reverse channel by a corresponding receiver.Type: GrantFiled: February 22, 1996Date of Patent: March 9, 1999Assignee: Globespan Technologies, Inc.Inventors: Hanan Herzberg, Ehud Langberg, Jin-Der Wang, Jean-Jacques Werner
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Patent number: 5828954Abstract: A digital audio broadcasting (DAB) system includes a radio-frequency (RF) transmitter and a corresponding RF receiver. The RF transmitter transmits an RF DAB signal that includes a pilot signal at 250 Khz. An RF section of the RF receiver includes a phase-lock-loop (PLL) to compensate for any carrier frequency differences in the received RF DAB signal. This PLL tracks the phase of the received RF DAB signal when an amplitude of a recovered IF signal is above a predetermined threshold and upon detection of the pilot signal.Type: GrantFiled: April 4, 1996Date of Patent: October 27, 1998Assignee: Lucent Technologies Inc.Inventor: Jin-Der Wang
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Patent number: 5822368Abstract: A digital audio broadcasting (DAB) system includes a radio-frequency (RF) receiver that develops a characterization signal representative of a respective mobile communications channel as a precursor to estimating a channel impulse response. The latter is used to set coefficients of an equalizer of the receiver to compensate for distortion such as intersymbol interference. In generating the channel impulse response a Fast Fourier Transform (FFT) of the characterization signal is performed. The resulting FFT is then clipped such that frequency components above a predetermined upper threshold and less than a predetermined lower threshold are set to the respective threshold values. This allows coefficients for the equalizer to be generated such that the equalizer converges even in the presence of strong reflections in a mobile communications environment.Type: GrantFiled: April 4, 1996Date of Patent: October 13, 1998Assignee: Lucent Technologies Inc.Inventor: Jin-Der Wang
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Patent number: 5815529Abstract: A digital audio broadcasting system includes an RF transmitter and a corresponding RF receiver. In the RF transmitter, a digitally compressed audio signal is encoded into a symbol stream that is first rotated using a frequency of 150,000 hertz (hz) before transmission to the RF receiver.Type: GrantFiled: April 4, 1996Date of Patent: September 29, 1998Assignee: Lucent Technologies Inc.Inventor: Jin-Der Wang
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Patent number: 5802079Abstract: A digital audio broadcasting (DAB) system includes a radio-frequency (RF) transmitter and a corresponding RF receiver that includes a frame detection circuit for providing a frame synchronization signal. The latter is used to inhibit a Reed-Solomon decoder from correcting data in any frame for which there was no synchronization.Type: GrantFiled: April 4, 1996Date of Patent: September 1, 1998Assignee: Lucent Technologies Inc.Inventor: Jin-Der Wang
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Patent number: 5751774Abstract: A digital audio broadcasting (DAB) system includes a radio-frequency (RF) transmitter and a corresponding RF receiver. The RF transmitter formats a DAB signal into a sequence of frames, each frame having a header comprising a predefined grouping of psuedo-random number sequences comprising 100 symbols. Of these 100 symbols, 86 symbols of the header are used for frame synchronization and channel sounding (for characterization of a communications channel), while the remaining 14 symbols are used for interleaver and data synchronization in an interleaved fashion.Type: GrantFiled: April 4, 1996Date of Patent: May 12, 1998Assignee: Lucent Technologies Inc.Inventor: Jin-Der Wang
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Patent number: 5748686Abstract: In a digital audio broadcasting (DAB) system having a radio-frequency (RF) transmitter and a corresponding RF receiver, a system and method for providing improved frame synchronization is provided. In accordance with the preferred embodiment, the RF transmitter formats a DAB signal into a sequence of frames, each frame having a header with a predefined grouping of psuedo-random number sequences comprising 100 symbols. Of these 100 symbols, 86 symbols of the header preferable are used for frame synchronization and characterization of a communications channel, while the remaining 14 symbols are used for interleaver and data synchronization in an interleaved fashion. The formatted DAB signal, including the frame sequences, is transmitted to the receiver preferably using quadrature phase-shift keying modulation. At the receiver, a correlator, utilizing a synchronization detection algorithm, is generally designed to match a predetermined symbol pattern within the received signal.Type: GrantFiled: April 4, 1996Date of Patent: May 5, 1998Assignee: Globespan Technologies, Inc.Inventors: Ehud Langberg, Jin-Der Wang
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Patent number: 5604769Abstract: A hybrid type of decision feedback equalizer (DFE) structure that approaches optimal DFE performance is described. The hybrid DFE includes both an intersymbol interference DFE (ISI-DFE) and a noise predictive DFE (NP-DFE). In particular, an adaptive feedforward filter section is followed by both an intersymbol interference (ISI) predictive filter and a noise predictive (NP) filter. The corresponding transmitter uses a precoder that utilizes optimal coefficient values, denoted as C(z), of the hybrid DFE structure. In particular, C(z) is equal to (1+I(z)) (1+N(z))-1, where, the notation I(z) and N(z), as known in the art, represent the resulting coefficient values after adaptation of the ISI-DFE and the NP-DFE, respectively.Type: GrantFiled: October 13, 1994Date of Patent: February 18, 1997Assignee: Lucent Technologies Inc.Inventor: Jin-Der Wang