Fang Ye Z Lu

US Patent:

RE37826, Sep 3, 2002

Filed:

Feb 18, 1999

Appl. No.:

09/252551

Inventors:

Henry Samueli - San Juan Capistrano CA
Mark Berman - Tustin CA
Fang Lu - Irvine CA

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H03H 730

US Classification:

370402, 370447, 375231, 375345, 375356

Abstract:

Four (4) unshielded twisted pairs of wires connect a hub and a computer in an Ethernet system: one (1) pair for transmission only, another for reception only and the other two (2) for transmission and reception. The signals in the wires are in packets each having timing signals defining a preamble and thereafter having digital signals representing information as by individual ones of three (3) amplitude levels. The signals received at the computer are provided with an automatic gain control (AGC) and then with digital conversions at a particular rate. A control loop operative upon the digital conversions regulates the AGC gain at a particular value. An equalizer operative only during the occurrence of the digital signals in each packet selects an individual one of the three (3) amplitude levels closest to the amplitude of each digital conversion at the time assumed to constitute the conversion peak. The amplitudes of the timing signals in each preamble at the times assumed to constitute the peaks and zero crossings of such signals are multiplied. The rate of such digital conversions is adjusted in accordance with the polarity and magnitude of the multiplication product.

US Patent:

6445039, Sep 3, 2002

Filed:

Jan 14, 2000

Appl. No.:

09/483551

Inventors:

Agnes N. Woo - Encino CA
Kenneth R. Kindsfater - Irvine CA
Fang Lu - Irvine CA

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H01L 2972

US Classification:

257355, 257356, 257357, 257360

Abstract:

An integrated receiver with channel selection and image rejection substantially implemented on a single CMOS integrated circuit is described. A receiver front end provides programmable attenuation and a programmable gain low noise amplifier. Frequency conversion circuitry advantageously uses LC filters integrated onto the substrate in conjunction with image reject mixers to provide sufficient image frequency rejection. Filter tuning and inductor Q compensation over temperature are performed on chip. The filters utilize multi track spiral inductors. The filters are tuned using local oscillators to tune a substitute filter, and frequency scaling during filter component values to those of the filter being tuned. In conjunction with filtering, frequency planning provides additional image rejection. The advantageous choice of local oscillator signal generation methods on chip is by PLL out of band local oscillation and by direct synthesis for in band local oscillator.

US Patent:

6459730, Oct 1, 2002

Filed:

Jan 13, 2000

Appl. No.:

09/482699

Inventors:

Henry Samueli - Northridge CA
Fang Lu - Irvine CA
Avanindra Madisetti - Torrance CA

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H04L 2701

US Classification:

375233, 375350

Abstract:

Digital signals provided by a repeater connected to a plurality of clients by unshielded twisted wire pairs, are converted to analog signals which become degraded during transmission through the wires. Clients convert the degraded analog signals to digital signals. Digital signal phases are coarsely adjusted to have assumed zero crossing times coincide in-time with a clock signal zero crossing. Signal polarity, and the polarity of any change, is determined at the assumed zero crossing times of the digital signals. Pre-cursor and post-cursor responses, resulting from signal degradation, are respectively inhibited by a feed forward and a decision feedback equalizer. The time duration of post-cursor response is further inhibited by a high pass filter and a tail canceller. Phase adjustments are made, after response inhibition, by determining the polarity, and the polarity of any change, at the assumed zero crossing times. Before phase adjustments are made, a phase offset is provided in order to compensate for phase degradations introduced by the unshielded twisted wire pairs.

US Patent:

6650624, Nov 18, 2003

Filed:

May 19, 2000

Appl. No.:

09/574558

Inventors:

Thomas J. Quigley - Lawrenceville GA
Jonathan S. Min - Buena Park CA
Lisa V. Denney - Suwanee GA
Henry Samueli - Corona Del Mar CA
Sean F. Nazareth - Anaheim Hills CA
Feng Chen - Irvine CA
Fang Lu - Irvine CA
Christopher R. Jones - Newport Beach CA

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H04L 1228

US Classification:

370252, 375222

Abstract:

A number of features for enhancing the performance of a cable transmission system in which data is transmitted between a cable modem termination system at a headend and a plurality of cable modems located different distances from the headend. The power transmission level, slot timing, and equalization of the cable modems are set by a ranging process. Data is transmitted by the modems in fragmented form. Various measures are taken to make transmission from the cable modems robust. The upstream data transmission is controlled to permit multiple access from the cable modems.

US Patent:

6690753, Feb 10, 2004

Filed:

Jun 7, 2002

Appl. No.:

10/163871

Inventors:

Thomas D. Kwon - Milpitas CA
Jonathan S. Min - Buena Park CA
Fang Lu - Irvine CA
Thomas J. Kolze - Phoenix AZ

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H04L 100

US Classification:

375344, 375350, 375348

Abstract:

A receiver includes a filter for filtering a received signal to produce a filtered signal. A converter converts the filtered signal to a baseband signal that is substantially free of an initial frequency offset and inter-symbol interference (ISI), responsive to a frequency-offset estimate and a restorative signal that compensates for the ISI. A detector detects symbols in the baseband signal to produce a decision signal. A restorative signal generator generates, from the decision signal, the restorative signal responsive to the frequency-offset estimate, such that the restorative signal compensates for the ISI.

US Patent:

6711227, Mar 23, 2004

Filed:

Feb 4, 2000

Appl. No.:

09/498162

Inventors:

Tarek Kaylani - Irvine CA
Fang Lu - Irvine CA
Henry Samueli - San Juan Capistrano CA

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H04L 2540

US Classification:

375372, 375373, 370516, 711149, 711209

Abstract:

To synchronize a regularly occurring pulse train to the average of a bunched pulse train, an oscillator generates a plurality of differently phase shifted signals at a given frequency. One of the phase shifted signals is selected as an output signal. The output signal is compared with the bunched pulse train. The selected phase shifted signal is changed responsive to the comparison so the output signal occurs at the average frequency of the bunched pulse train. The oscillator is formed as a plurality of differential amplifier stages having equal controllable delays. The stages are connected together to form a ring oscillator. The output signal is compared with the bunched pulse train through a FIFO. A signal representative of the state of the FIFO is used as an error signal to control the selection of the phase shifted signal to be used as the output signal. A phase locked loop that synchronizes the phase shifted signal generating oscillator to a frequency reference is nested in the control loop that selects one of the phase shifted signals as the output signal.

US Patent:

6763032, Jul 13, 2004

Filed:

Feb 10, 2000

Appl. No.:

09/501892

Inventors:

Theodore F. Rabenko - Duluth GA
James C. H. Thi - Irvine CA
Thomas J. Quigley - Lawrenceville GA
Lisa V. Denney - Suwanee GA
Jonathan S. Min - Buena Park CA
Christopher R. Jones - Newport Beach CA
Henry Samueli - San Juan Capistrano CA
Fang Lu - Irvine CA
Feng Chen - Irvine CA
Sean F. Nazareth - Anaheim Hills CA

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H04B 7212

US Classification:

370442, 370488

Abstract:

A method for communicating information is disclosed wherein a time slot is allocated in a time division multiple access system for a transmission from a subscriber to a headend. Synchronization of a clock of the subscriber with respect to a clock of the headend is enhanced using a message transmitted from the headend to the subscriber which is indicative of an error in a subscriber transmission time with respect to the time slot. A feedback loop process is used to determine at least one of fractional symbol timing correction and carrier phase correction of a transmission from the subscriber to the headend. Filter coefficients are generated at the headend from a ranging signal transmitted from the subscriber to the headend and transmitting the filter coefficients from the headend to the subscriber, the filter coefficients being used by the subscriber to compensate for noise in a transmission from the subscriber to the headend.

US Patent:

6961314, Nov 1, 2005

Filed:

Aug 25, 2000

Appl. No.:

09/648895

Inventors:

Thomas J. Quigley - Lawrenceville GA, US
Jonathan S. Min - Buena Park CA, US
Lisa V. Denney - Suwanee GA, US
Henry Samueli - Corona Del Mar CA, US
Sean F. Nazareth - Anaheim Hills CA, US
Feng Chen - Irvine CA, US
Fang Lu - Irvine CA, US
Christopher R. Jones - Newport Beach CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H04L012/28

US Classification:

370252, 370352, 375222

Abstract:

A number of features for enhancing the performance of a cable transmission system in which data is transmitted between a cable modem termination system at a headend and a plurality of cable modems located different distances from the headend. The power transmission level, slot timing, and equalization of the cable modems are set by a ranging process. Data is transmitted by the modems in fragmented form. Various measures are taken to make transmission from the cable modems robust. The upstream data transmission is controlled to permit multiple access from the cable modems.